add trie, add mini Json
parent
fdd791dcd5
commit
bbd498482a
@ -0,0 +1,681 @@
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package org.xbib.datastructures.json.mini;
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import java.io.IOException;
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import java.time.Instant;
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import java.util.Collection;
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import java.util.Deque;
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import java.util.LinkedHashMap;
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import java.util.LinkedList;
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import java.util.List;
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import java.util.Map;
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import java.util.Objects;
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/**
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* A minimal JSON parser and generator for Java Maps and Collections.
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*/
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public class Json {
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private Json() {
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}
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public static String toString(Map<String, Object> map) throws IOException {
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return map != null ? new JsonBuilder().buildMap(map).build() : null;
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}
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public static String toString(Collection<Object> collection) throws IOException {
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return collection != null ? new JsonBuilder().buildCollection(collection).build() : null;
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}
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@SuppressWarnings("unchecked")
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public static Map<String, Object> toMap(String json) throws IOException {
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if (json == null) {
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return null;
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}
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JsonParser parser = new JsonParser();
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parser.parse(json);
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Object object = parser.getResult();
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if (object instanceof Map) {
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return (Map<String, Object>) parser.getResult();
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}
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throw new IllegalArgumentException(("unexpected, not a map instance: " + object.getClass()));
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}
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@SuppressWarnings("unchecked")
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public static Collection<Object> toCollection(String json) throws IOException {
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if (json == null) {
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return null;
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}
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JsonParser parser = new JsonParser();
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parser.parse(json);
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Object object = parser.getResult();
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if (object instanceof Collection) {
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return (Collection<Object>) parser.getResult();
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}
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throw new IllegalArgumentException(("unexpected, not a collection instance: " + object.getClass()));
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}
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private static class JsonParser {
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private static final char EOS = (char) -1;
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private static final char DOUBLE_QUOTE = '"';
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private static final char BACKSLASH = '\\';
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private static final char OPEN_MAP = '{';
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private static final char CLOSE_MAP = '}';
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private static final char OPEN_LIST = '[';
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private static final char CLOSE_LIST = ']';
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private static final char COMMA = ',';
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private static final char COLON = ':';
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private String input;
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private int i;
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private char ch;
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private Object result;
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private final Deque<Object> stack = new LinkedList<>();
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public JsonParser() {
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}
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public void parse(String input) throws IOException {
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Objects.requireNonNull(input);
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this.input = input;
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this.i = 0;
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stack.clear();
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ch = next();
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skipWhitespace();
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parseValue();
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skipWhitespace();
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if (ch != EOS) {
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throw new IOException("malformed json: " + ch);
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}
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}
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public Object getResult() {
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return result;
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}
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private void parseValue() throws IOException {
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switch (ch) {
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case DOUBLE_QUOTE:
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ch = next();
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parseString(false);
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break;
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case OPEN_MAP:
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parseMap();
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break;
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case OPEN_LIST:
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parseList();
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break;
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case '0':
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case '1':
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case '2':
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case '3':
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case '4':
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case '5':
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case '6':
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case '7':
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case '8':
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case '9':
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case '-':
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parseNumber();
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break;
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case 't':
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parseTrue();
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break;
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case 'f':
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parseFalse();
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break;
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case 'n':
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parseNull();
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break;
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default:
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throw new IOException("illegal character: " + ch);
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}
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}
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private void parseNumber() throws IOException {
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boolean minus = false;
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boolean dot = false;
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boolean exponent = false;
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int start = i - 1;
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while (true) {
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if (ch == '-') {
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if (i - start > 1) {
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throw new IOException("minus inside number");
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}
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ch =next();
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minus = true;
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} else if (ch == 'e' || ch == 'E') {
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ch = next();
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if (exponent) {
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throw new IOException("double exponents");
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}
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exponent = true;
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ch = next();
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if (ch == '-' || ch == '+') {
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ch = next();
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if (ch < '0' || ch > '9') {
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throw new IOException("invalid exponent");
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}
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} else if (ch < '0' || ch > '9') {
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throw new IOException("invalid exponent");
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}
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} else if (ch == '.') {
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ch = next();
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if (dot) {
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throw new IOException("multiple dots");
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}
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if (i - start == 1) {
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throw new IOException("no digit before dot");
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}
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dot = true;
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} else if (ch >= '0' && ch <= '9') {
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ch = next();
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} else {
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break;
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}
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}
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if (minus && i - start == 1) {
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throw new IOException("isolated minus");
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}
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if (dot || exponent) {
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valueNode(Double.parseDouble(input.substring(start, i - 1)));
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} else {
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valueNode(Long.parseLong(input.substring(start, i - 1)));
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}
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}
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private void parseString(boolean isKey) throws IOException {
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boolean escaped = false;
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int start = i - 1;
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while (true) {
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if (ch == DOUBLE_QUOTE) {
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if (escaped) {
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CharSequence s = unescape(input.substring(start, i - 1));
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if (isKey) {
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stack.push(new KeyNode(s));
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} else {
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valueNode(s);
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}
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} else {
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if (isKey) {
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stack.push(new KeyNode(input.substring(start, i - 1)));
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} else {
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valueNode(input.substring(start, i - 1));
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}
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}
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ch = next();
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return;
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} else if (ch == BACKSLASH) {
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escaped = true;
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ch = next();
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if (ch == DOUBLE_QUOTE || ch == '/' || ch == BACKSLASH || ch == 'b' || ch == 'f' || ch == 'n' || ch == 'r' || ch == 't') {
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ch = next();
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} else if (ch == 'u') {
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expectHex();
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expectHex();
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expectHex();
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expectHex();
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} else {
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throw new IOException("illegal escape char: " + ch);
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}
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} else if (ch < 32) {
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throw new IOException("illegal control char: " + ch);
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} else {
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ch = next();
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}
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}
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}
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private void parseList() throws IOException {
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int count = 0;
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List<Object> list = new LinkedList<>();
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stack.push(list);
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ch = next();
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while (true) {
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skipWhitespace();
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if (ch == CLOSE_LIST) {
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result = stack.pop();
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tryAppend(result);
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ch = next();
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return;
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}
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if (count > 0) {
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expectChar(COMMA);
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ch = next();
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skipWhitespace();
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}
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parseValue();
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count++;
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}
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}
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private void parseMap() throws IOException {
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int count = 0;
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Map<String, Object> map = new LinkedHashMap<>();
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stack.push(map);
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ch = next();
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while (true) {
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skipWhitespace();
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if (ch == CLOSE_MAP) {
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result = stack.pop();
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tryAppend(result);
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ch = next();
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return;
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}
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if (count > 0) {
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expectChar(COMMA);
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ch = next();
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skipWhitespace();
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}
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expectChar(DOUBLE_QUOTE);
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ch = next();
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parseString(true);
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skipWhitespace();
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expectChar(COLON);
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ch = next();
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skipWhitespace();
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parseValue();
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count++;
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}
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}
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private void parseNull() throws IOException {
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ch = next();
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expectChar('u');
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ch = next();
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expectChar('l');
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ch = next();
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expectChar('l');
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valueNode(null);
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ch = next();
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}
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private void parseTrue() throws IOException {
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ch = next();
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expectChar('r');
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ch = next();
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expectChar('u');
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ch = next();
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expectChar('e');
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valueNode(true);
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ch = next();
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}
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private void parseFalse() throws IOException {
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ch = next();
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expectChar('a');
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ch = next();
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expectChar('l');
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ch = next();
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expectChar('s');
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ch = next();
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expectChar('e');
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valueNode(false);
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ch = next();
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}
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private void expectChar(char expected) throws IOException {
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if (ch != expected) {
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throw new IOException("expected char " + expected + " but got " + ch);
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}
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}
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private void expectHex() throws IOException {
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ch = next();
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if ((ch >= '0' && ch <= '9') || (ch >= 'a' && ch <= 'f') || (ch >= 'A' && ch <= 'F')) {
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return;
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}
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throw new IOException("invalid hex char " + ch);
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}
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private void skipWhitespace() {
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while (ch == ' ' || ch == '\t' || ch == '\n' || ch == '\r') {
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ch = next();
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}
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}
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private static CharSequence unescape(CharSequence input) {
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StringBuilder result = new StringBuilder(input.length());
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int i = 0;
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while (i < input.length()) {
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if (input.charAt(i) == BACKSLASH) {
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i++;
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switch (input.charAt(i)) {
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case BACKSLASH:
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result.append(BACKSLASH);
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break;
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case '/':
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result.append('/');
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break;
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case DOUBLE_QUOTE:
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result.append(DOUBLE_QUOTE);
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break;
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case 'b':
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result.append('\b');
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break;
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case 'f':
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result.append('\f');
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break;
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case 'n':
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result.append('\n');
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break;
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case 'r':
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result.append('\r');
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break;
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case 't':
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result.append('\t');
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break;
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case 'u': {
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result.append(Character.toChars(Integer.parseInt(input.toString().substring(i + 1, i + 5), 16)));
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i += 4;
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}
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}
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} else {
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result.append(input.charAt(i));
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}
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i++;
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}
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return result;
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}
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private char next() {
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try {
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return input.charAt(i++);
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} catch (StringIndexOutOfBoundsException e) {
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return (char) -1;
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}
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}
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private void valueNode(Object object) {
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if (!tryAppend(object)) {
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stack.push(object);
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result = object;
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}
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}
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@SuppressWarnings("unchecked")
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private boolean tryAppend(Object object) {
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if (!stack.isEmpty()) {
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if (stack.peek() instanceof List) {
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@SuppressWarnings("unchecked")
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List<Object> list = (List<Object>) stack.peek();
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list.add(object);
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return true;
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} else if (stack.peek() instanceof KeyNode){
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KeyNode key = (KeyNode) stack.pop();
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if (stack.peek() instanceof Map) {
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@SuppressWarnings("unchecked")
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Map<String, Object> map = (Map<String, Object>) stack.peek();
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if (map != null) {
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String k = key != null ? key.get().toString() : null;
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map.put(k, object);
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return true;
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}
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}
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}
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}
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return false;
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}
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}
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static class KeyNode {
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private final CharSequence value;
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public KeyNode(CharSequence value) {
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this.value = value;
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}
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public CharSequence get() {
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return value;
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}
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}
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static class JsonBuilder {
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private final Appendable appendable;
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private State state;
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protected JsonBuilder() {
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this(new StringBuilder());
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}
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protected JsonBuilder(Appendable appendable) {
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this.appendable = appendable;
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this.state = new State(null, 0, Structure.DOCSTART, true);
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}
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public JsonBuilder beginCollection() throws IOException {
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this.state = new State(state, state.level + 1, Structure.COLLECTION, true);
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appendable.append('[');
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return this;
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}
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public JsonBuilder endCollection() throws IOException {
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if (state.structure != Structure.COLLECTION) {
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throw new IOException("no array to close");
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}
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appendable.append(']');
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this.state = state != null ? state.parent : null;
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return this;
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}
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public JsonBuilder beginMap() throws IOException {
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if (state.structure == Structure.COLLECTION) {
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beginArrayValue();
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}
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this.state = new State(state, state.level + 1, Structure.MAP, true);
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appendable.append('{');
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return this;
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}
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public JsonBuilder endMap() throws IOException {
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if (state.structure != Structure.MAP && state.structure != Structure.KEY) {
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throw new IOException("no object to close");
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}
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appendable.append('}');
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this.state = state != null ? state.parent : null;
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return this;
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}
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public JsonBuilder buildMap(Map<String, Object> map) throws IOException {
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Objects.requireNonNull(map);
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boolean wrap = state.structure != Structure.MAP;
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if (wrap) {
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beginMap();
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}
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for (Map.Entry<String, Object> entry : map.entrySet()) {
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buildKey(entry.getKey());
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buildValue(entry.getValue());
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}
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if (wrap) {
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endMap();
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}
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return this;
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}
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public JsonBuilder buildCollection(Collection<?> collection) throws IOException {
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Objects.requireNonNull(collection);
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beginCollection();
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for (Object object : collection) {
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buildValue(object);
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}
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endCollection();
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return this;
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}
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@SuppressWarnings("unchecked")
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public JsonBuilder buildValue(Object object) throws IOException {
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if (object instanceof Map) {
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buildMap((Map<String, Object>) object);
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return this;
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} else if (object instanceof Collection) {
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buildCollection((Collection<Object>) object);
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return this;
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}
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if (state.structure == Structure.COLLECTION) {
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beginArrayValue();
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}
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if (object == null) {
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buildNull();
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} else if (object instanceof CharSequence) {
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buildString((CharSequence) object, true);
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} else if (object instanceof Boolean) {
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buildBoolean((Boolean) object);
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} else if (object instanceof Byte) {
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buildNumber((byte) object);
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} else if (object instanceof Integer) {
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buildNumber((int) object);
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} else if (object instanceof Long) {
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buildNumber((long) object);
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} else if (object instanceof Float) {
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buildNumber((float) object);
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} else if (object instanceof Double) {
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buildNumber((double) object);
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} else if (object instanceof Number) {
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buildNumber((Number) object);
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} else if (object instanceof Instant) {
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buildInstant((Instant) object);
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} else {
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throw new IllegalArgumentException("unable to write object class " + object.getClass());
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}
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return this;
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}
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public JsonBuilder buildKey(CharSequence string) throws IOException {
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if (state.structure == Structure.COLLECTION) {
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beginArrayValue();
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} else if (state.structure == Structure.MAP || state.structure == Structure.KEY) {
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beginKey(string != null ? string.toString() : null);
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}
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buildString(string, true);
|
||||
if (state.structure == Structure.MAP || state.structure == Structure.KEY) {
|
||||
endKey(string != null ? string.toString() : null);
|
||||
}
|
||||
state.structure = Structure.KEY;
|
||||
return this;
|
||||
}
|
||||
|
||||
public JsonBuilder buildNull() throws IOException {
|
||||
if (state.structure == Structure.COLLECTION) {
|
||||
beginArrayValue();
|
||||
}
|
||||
buildString("null", false);
|
||||
return this;
|
||||
}
|
||||
|
||||
public String build() {
|
||||
return appendable.toString();
|
||||
}
|
||||
|
||||
private void beginKey(String k) throws IOException {
|
||||
if (state.first) {
|
||||
state.first = false;
|
||||
} else {
|
||||
appendable.append(",");
|
||||
}
|
||||
}
|
||||
|
||||
private void endKey(String k) throws IOException {
|
||||
appendable.append(":");
|
||||
}
|
||||
|
||||
private void beginArrayValue() throws IOException {
|
||||
if (state.first) {
|
||||
state.first = false;
|
||||
} else {
|
||||
appendable.append(",");
|
||||
}
|
||||
}
|
||||
|
||||
private void buildBoolean(boolean bool) throws IOException {
|
||||
buildString(bool ? "true" : "false", false);
|
||||
}
|
||||
|
||||
private void buildNumber(Number number) throws IOException {
|
||||
buildString(number != null ? number.toString() : null, false);
|
||||
}
|
||||
|
||||
private void buildInstant(Instant instant) throws IOException {
|
||||
buildString(instant.toString(), true);
|
||||
}
|
||||
|
||||
private void buildString(CharSequence string, boolean escape) throws IOException {
|
||||
appendable.append(escape ? escapeString(string) : string);
|
||||
}
|
||||
|
||||
private CharSequence escapeString(CharSequence string) {
|
||||
StringBuilder sb = new StringBuilder();
|
||||
sb.append('"');
|
||||
int start = 0;
|
||||
int l = string.length();
|
||||
for (int i = 0; i < l; i++) {
|
||||
char c = string.charAt(i);
|
||||
if (c == '"' || c == '\\' || c < 32) {
|
||||
if (i > start) {
|
||||
sb.append(string, start, i);
|
||||
}
|
||||
start = i + 1;
|
||||
sb.append(escapeCharacter(c));
|
||||
}
|
||||
}
|
||||
if (l > start) {
|
||||
sb.append(string, start, l);
|
||||
}
|
||||
sb.append('"');
|
||||
return sb;
|
||||
}
|
||||
|
||||
private static String escapeCharacter(char c) {
|
||||
switch (c) {
|
||||
case '\n':
|
||||
return "\\n";
|
||||
case '\r':
|
||||
return "\\r";
|
||||
case '\t':
|
||||
return "\\t";
|
||||
case '\\':
|
||||
return "\\\\";
|
||||
case '\'':
|
||||
return "\\'";
|
||||
case '\"':
|
||||
return "\\\"";
|
||||
}
|
||||
String hex = Integer.toHexString(c);
|
||||
return "\\u0000".substring(0, 6 - hex.length()) + hex;
|
||||
}
|
||||
|
||||
private enum Structure {
|
||||
DOCSTART, MAP, KEY, COLLECTION
|
||||
}
|
||||
|
||||
private static class State {
|
||||
State parent;
|
||||
int level;
|
||||
Structure structure;
|
||||
boolean first;
|
||||
|
||||
State(State parent, int level, Structure structure, boolean first) {
|
||||
this.parent = parent;
|
||||
this.level = level;
|
||||
this.structure = structure;
|
||||
this.first = first;
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
@ -0,0 +1,907 @@
|
||||
package org.xbib.datastructures.trie.concurrent;
|
||||
|
||||
import org.xbib.datastructures.trie.concurrent.util.CharSequences;
|
||||
import org.xbib.datastructures.trie.concurrent.util.KeyValuePair;
|
||||
import org.xbib.datastructures.trie.concurrent.util.LazyIterator;
|
||||
import org.xbib.datastructures.trie.concurrent.util.Node;
|
||||
import org.xbib.datastructures.trie.concurrent.util.NodeFactory;
|
||||
|
||||
import java.util.ArrayList;
|
||||
import java.util.Arrays;
|
||||
import java.util.Collections;
|
||||
import java.util.Deque;
|
||||
import java.util.Iterator;
|
||||
import java.util.LinkedList;
|
||||
import java.util.List;
|
||||
import java.util.concurrent.locks.Lock;
|
||||
import java.util.concurrent.locks.ReentrantLock;
|
||||
|
||||
import static org.xbib.datastructures.trie.concurrent.ConcurrentRadixTree.SearchResult.Classification;
|
||||
|
||||
/**
|
||||
* An implementation of {@link RadixTree} which supports lock-free concurrent reads, and allows items to be added to and
|
||||
* to be removed from the tree <i>atomically</i> by background thread(s), without blocking reads.
|
||||
* <p/>
|
||||
* Unlike reads, writes require locking of the tree (locking out other writing threads only; reading threads are never
|
||||
* blocked). Currently write locks are coarse-grained; in fact they are tree-level. In future branch-level write locks
|
||||
* might be added, but the current implementation is targeted at high concurrency read-mostly use cases.
|
||||
*/
|
||||
public class ConcurrentRadixTree<O> implements RadixTree<O> {
|
||||
|
||||
private final NodeFactory nodeFactory;
|
||||
|
||||
protected volatile Node root;
|
||||
|
||||
// Write operations acquire write lock, read operations are lock-free.
|
||||
private final Lock writeLock = new ReentrantLock();
|
||||
|
||||
/**
|
||||
* Creates a new {@link ConcurrentRadixTree} which will use the given {@link NodeFactory} to create nodes.
|
||||
*
|
||||
* @param nodeFactory An object which creates {@link Node} objects on-demand, and which might return node
|
||||
* implementations optimized for storing the values supplied to it for the creation of each node
|
||||
*/
|
||||
public ConcurrentRadixTree(NodeFactory nodeFactory) {
|
||||
this.nodeFactory = nodeFactory;
|
||||
this.root = nodeFactory.createNode("", null, Collections.emptyList(), true);
|
||||
}
|
||||
|
||||
protected void acquireWriteLock() {
|
||||
writeLock.lock();
|
||||
}
|
||||
|
||||
protected void releaseWriteLock() {
|
||||
writeLock.unlock();
|
||||
}
|
||||
|
||||
@Override
|
||||
public O put(CharSequence key, O value) {
|
||||
@SuppressWarnings({"unchecked", "UnnecessaryLocalVariable"})
|
||||
O existingValue = (O) putInternal(key, value, true); // putInternal acquires write lock
|
||||
return existingValue;
|
||||
}
|
||||
|
||||
@Override
|
||||
public O putIfAbsent(CharSequence key, O value) {
|
||||
@SuppressWarnings({"unchecked", "UnnecessaryLocalVariable"})
|
||||
O existingValue = (O) putInternal(key, value, false); // putInternal acquires write lock
|
||||
return existingValue;
|
||||
}
|
||||
|
||||
@Override
|
||||
public O getValueForExactKey(CharSequence key) {
|
||||
SearchResult searchResult = searchTree(key);
|
||||
if (searchResult.classification.equals(SearchResult.Classification.EXACT_MATCH)) {
|
||||
@SuppressWarnings({"unchecked", "UnnecessaryLocalVariable"})
|
||||
O value = (O) searchResult.nodeFound.getValue();
|
||||
return value;
|
||||
}
|
||||
return null;
|
||||
}
|
||||
|
||||
@Override
|
||||
public Iterable<CharSequence> getKeysStartingWith(CharSequence prefix) {
|
||||
SearchResult searchResult = searchTree(prefix);
|
||||
Classification classification = searchResult.classification;
|
||||
switch (classification) {
|
||||
case EXACT_MATCH: {
|
||||
return getDescendantKeys(prefix, searchResult.nodeFound);
|
||||
}
|
||||
case KEY_ENDS_MID_EDGE: {
|
||||
// Append the remaining characters of the edge to the key.
|
||||
// For example if we searched for CO, but first matching node was COFFEE,
|
||||
// the key associated with the first node should be COFFEE...
|
||||
CharSequence edgeSuffix = CharSequences.getSuffix(searchResult.nodeFound.getIncomingEdge(), searchResult.charsMatchedInNodeFound);
|
||||
prefix = CharSequences.concatenate(prefix, edgeSuffix);
|
||||
return getDescendantKeys(prefix, searchResult.nodeFound);
|
||||
}
|
||||
default: {
|
||||
// Incomplete match means key is not a prefix of any node...
|
||||
return Collections.emptySet();
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
@Override
|
||||
public Iterable<O> getValuesForKeysStartingWith(CharSequence prefix) {
|
||||
SearchResult searchResult = searchTree(prefix);
|
||||
Classification classification = searchResult.classification;
|
||||
switch (classification) {
|
||||
case EXACT_MATCH: {
|
||||
return getDescendantValues(prefix, searchResult.nodeFound);
|
||||
}
|
||||
case KEY_ENDS_MID_EDGE: {
|
||||
// Append the remaining characters of the edge to the key.
|
||||
// For example if we searched for CO, but first matching node was COFFEE,
|
||||
// the key associated with the first node should be COFFEE...
|
||||
CharSequence edgeSuffix = CharSequences.getSuffix(searchResult.nodeFound.getIncomingEdge(), searchResult.charsMatchedInNodeFound);
|
||||
prefix = CharSequences.concatenate(prefix, edgeSuffix);
|
||||
return getDescendantValues(prefix, searchResult.nodeFound);
|
||||
}
|
||||
default: {
|
||||
// Incomplete match means key is not a prefix of any node...
|
||||
return Collections.emptySet();
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
@Override
|
||||
public Iterable<KeyValuePair<O>> getKeyValuePairsForKeysStartingWith(CharSequence prefix) {
|
||||
SearchResult searchResult = searchTree(prefix);
|
||||
Classification classification = searchResult.classification;
|
||||
switch (classification) {
|
||||
case EXACT_MATCH: {
|
||||
return getDescendantKeyValuePairs(prefix, searchResult.nodeFound);
|
||||
}
|
||||
case KEY_ENDS_MID_EDGE: {
|
||||
// Append the remaining characters of the edge to the key.
|
||||
// For example if we searched for CO, but first matching node was COFFEE,
|
||||
// the key associated with the first node should be COFFEE...
|
||||
CharSequence edgeSuffix = CharSequences.getSuffix(searchResult.nodeFound.getIncomingEdge(), searchResult.charsMatchedInNodeFound);
|
||||
prefix = CharSequences.concatenate(prefix, edgeSuffix);
|
||||
return getDescendantKeyValuePairs(prefix, searchResult.nodeFound);
|
||||
}
|
||||
default: {
|
||||
// Incomplete match means key is not a prefix of any node...
|
||||
return Collections.emptySet();
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
@Override
|
||||
public boolean remove(CharSequence key) {
|
||||
if (key == null) {
|
||||
throw new IllegalArgumentException("The key argument was null");
|
||||
}
|
||||
acquireWriteLock();
|
||||
try {
|
||||
SearchResult searchResult = searchTree(key);
|
||||
SearchResult.Classification classification = searchResult.classification;
|
||||
if (classification == Classification.EXACT_MATCH) {
|
||||
if (searchResult.nodeFound.getValue() == null) {
|
||||
// This node was created automatically as a split between two branches (implicit node).
|
||||
// No need to remove it...
|
||||
return false;
|
||||
}
|
||||
|
||||
// Proceed with deleting the node...
|
||||
List<Node> childEdges = searchResult.nodeFound.getOutgoingEdges();
|
||||
if (childEdges.size() > 1) {
|
||||
// This node has more than one child, so if we delete the value from this node, we still need
|
||||
// to leave a similar node in place to act as the split between the child edges.
|
||||
// Just delete the value associated with this node.
|
||||
// -> Clone this node without its value, preserving its child nodes...
|
||||
@SuppressWarnings({"NullableProblems"})
|
||||
Node cloned = nodeFactory.createNode(searchResult.nodeFound.getIncomingEdge(), null, searchResult.nodeFound.getOutgoingEdges(), false);
|
||||
// Re-add the replacement node to the parent...
|
||||
searchResult.parentNode.updateOutgoingEdge(cloned);
|
||||
} else if (childEdges.size() == 1) {
|
||||
// Node has one child edge.
|
||||
// Create a new node which is the concatenation of the edges from this node and its child,
|
||||
// and which has the outgoing edges of the child and the value from the child.
|
||||
Node child = childEdges.get(0);
|
||||
CharSequence concatenatedEdges = CharSequences.concatenate(searchResult.nodeFound.getIncomingEdge(), child.getIncomingEdge());
|
||||
Node mergedNode = nodeFactory.createNode(concatenatedEdges, child.getValue(), child.getOutgoingEdges(), false);
|
||||
// Re-add the merged node to the parent...
|
||||
searchResult.parentNode.updateOutgoingEdge(mergedNode);
|
||||
} else {
|
||||
// Node has no children. Delete this node from its parent,
|
||||
// which involves re-creating the parent rather than simply updating its child edge
|
||||
// (this is why we need parentNodesParent).
|
||||
// However if this would leave the parent with only one remaining child edge,
|
||||
// and the parent itself has no value (is a split node), and the parent is not the root node
|
||||
// (a special case which we never merge), then we also need to merge the parent with its
|
||||
// remaining child.
|
||||
|
||||
List<Node> currentEdgesFromParent = searchResult.parentNode.getOutgoingEdges();
|
||||
// Create a list of the outgoing edges of the parent which will remain
|
||||
// if we remove this child...
|
||||
// Use a non-resizable list, as a sanity check to force ArrayIndexOutOfBounds...
|
||||
List<Node> newEdgesOfParent = Arrays.asList(new Node[searchResult.parentNode.getOutgoingEdges().size() - 1]);
|
||||
for (int i = 0, added = 0, numParentEdges = currentEdgesFromParent.size(); i < numParentEdges; i++) {
|
||||
Node node = currentEdgesFromParent.get(i);
|
||||
if (node != searchResult.nodeFound) {
|
||||
newEdgesOfParent.set(added++, node);
|
||||
}
|
||||
}
|
||||
|
||||
// Note the parent might actually be the root node (which we should never merge)...
|
||||
boolean parentIsRoot = (searchResult.parentNode == root);
|
||||
Node newParent;
|
||||
if (newEdgesOfParent.size() == 1 && searchResult.parentNode.getValue() == null && !parentIsRoot) {
|
||||
// Parent is a non-root split node with only one remaining child, which can now be merged.
|
||||
Node parentsRemainingChild = newEdgesOfParent.get(0);
|
||||
// Merge the parent with its only remaining child...
|
||||
CharSequence concatenatedEdges = CharSequences.concatenate(searchResult.parentNode.getIncomingEdge(), parentsRemainingChild.getIncomingEdge());
|
||||
newParent = nodeFactory.createNode(concatenatedEdges, parentsRemainingChild.getValue(), parentsRemainingChild.getOutgoingEdges(), parentIsRoot);
|
||||
} else {
|
||||
// Parent is a node which either has a value of its own, has more than one remaining
|
||||
// child, or is actually the root node (we never merge the root node).
|
||||
// Create new parent node which is the same as is currently just without the edge to the
|
||||
// node being deleted...
|
||||
newParent = nodeFactory.createNode(searchResult.parentNode.getIncomingEdge(), searchResult.parentNode.getValue(), newEdgesOfParent, parentIsRoot);
|
||||
}
|
||||
// Re-add the parent node to its parent...
|
||||
if (parentIsRoot) {
|
||||
// Replace the root node...
|
||||
this.root = newParent;
|
||||
} else {
|
||||
// Re-add the parent node to its parent...
|
||||
searchResult.parentNodesParent.updateOutgoingEdge(newParent);
|
||||
}
|
||||
}
|
||||
return true;
|
||||
}
|
||||
return false;
|
||||
}
|
||||
finally {
|
||||
releaseWriteLock();
|
||||
}
|
||||
}
|
||||
|
||||
@Override
|
||||
public Iterable<CharSequence> getClosestKeys(CharSequence candidate) {
|
||||
SearchResult searchResult = searchTree(candidate);
|
||||
Classification classification = searchResult.classification;
|
||||
switch (classification) {
|
||||
case EXACT_MATCH: {
|
||||
return getDescendantKeys(candidate, searchResult.nodeFound);
|
||||
}
|
||||
case KEY_ENDS_MID_EDGE: {
|
||||
// Append the remaining characters of the edge to the key.
|
||||
// For example if we searched for CO, but first matching node was COFFEE,
|
||||
// the key associated with the first node should be COFFEE...
|
||||
CharSequence edgeSuffix = CharSequences.getSuffix(searchResult.nodeFound.getIncomingEdge(), searchResult.charsMatchedInNodeFound);
|
||||
candidate = CharSequences.concatenate(candidate, edgeSuffix);
|
||||
return getDescendantKeys(candidate, searchResult.nodeFound);
|
||||
}
|
||||
case INCOMPLETE_MATCH_TO_MIDDLE_OF_EDGE: {
|
||||
// Example: if we searched for CX, but deepest matching node was CO,
|
||||
// the results should include node CO and its descendants...
|
||||
CharSequence keyOfParentNode = CharSequences.getPrefix(candidate, searchResult.charsMatched - searchResult.charsMatchedInNodeFound);
|
||||
CharSequence keyOfNodeFound = CharSequences.concatenate(keyOfParentNode, searchResult.nodeFound.getIncomingEdge());
|
||||
return getDescendantKeys(keyOfNodeFound, searchResult.nodeFound);
|
||||
}
|
||||
case INCOMPLETE_MATCH_TO_END_OF_EDGE: {
|
||||
if (searchResult.charsMatched == 0) {
|
||||
// Closest match is the root node, we don't consider this a match for anything...
|
||||
break;
|
||||
}
|
||||
// Example: if we searched for COFFEE, but deepest matching node was CO,
|
||||
// the results should include node CO and its descendants...
|
||||
CharSequence keyOfNodeFound = CharSequences.getPrefix(candidate, searchResult.charsMatched);
|
||||
return getDescendantKeys(keyOfNodeFound, searchResult.nodeFound);
|
||||
}
|
||||
}
|
||||
return Collections.emptySet();
|
||||
}
|
||||
|
||||
@Override
|
||||
public Iterable<O> getValuesForClosestKeys(CharSequence candidate) {
|
||||
SearchResult searchResult = searchTree(candidate);
|
||||
Classification classification = searchResult.classification;
|
||||
switch (classification) {
|
||||
case EXACT_MATCH: {
|
||||
return getDescendantValues(candidate, searchResult.nodeFound);
|
||||
}
|
||||
case KEY_ENDS_MID_EDGE: {
|
||||
// Append the remaining characters of the edge to the key.
|
||||
// For example if we searched for CO, but first matching node was COFFEE,
|
||||
// the key associated with the first node should be COFFEE...
|
||||
CharSequence edgeSuffix = CharSequences.getSuffix(searchResult.nodeFound.getIncomingEdge(), searchResult.charsMatchedInNodeFound);
|
||||
candidate = CharSequences.concatenate(candidate, edgeSuffix);
|
||||
return getDescendantValues(candidate, searchResult.nodeFound);
|
||||
}
|
||||
case INCOMPLETE_MATCH_TO_MIDDLE_OF_EDGE: {
|
||||
// Example: if we searched for CX, but deepest matching node was CO,
|
||||
// the results should include node CO and its descendants...
|
||||
CharSequence keyOfParentNode = CharSequences.getPrefix(candidate, searchResult.charsMatched - searchResult.charsMatchedInNodeFound);
|
||||
CharSequence keyOfNodeFound = CharSequences.concatenate(keyOfParentNode, searchResult.nodeFound.getIncomingEdge());
|
||||
return getDescendantValues(keyOfNodeFound, searchResult.nodeFound);
|
||||
}
|
||||
case INCOMPLETE_MATCH_TO_END_OF_EDGE: {
|
||||
if (searchResult.charsMatched == 0) {
|
||||
// Closest match is the root node, we don't consider this a match for anything...
|
||||
break;
|
||||
}
|
||||
// Example: if we searched for COFFEE, but deepest matching node was CO,
|
||||
// the results should include node CO and its descendants...
|
||||
CharSequence keyOfNodeFound = CharSequences.getPrefix(candidate, searchResult.charsMatched);
|
||||
return getDescendantValues(keyOfNodeFound, searchResult.nodeFound);
|
||||
}
|
||||
}
|
||||
return Collections.emptySet();
|
||||
}
|
||||
|
||||
@Override
|
||||
public Iterable<KeyValuePair<O>> getKeyValuePairsForClosestKeys(CharSequence candidate) {
|
||||
SearchResult searchResult = searchTree(candidate);
|
||||
Classification classification = searchResult.classification;
|
||||
switch (classification) {
|
||||
case EXACT_MATCH: {
|
||||
return getDescendantKeyValuePairs(candidate, searchResult.nodeFound);
|
||||
}
|
||||
case KEY_ENDS_MID_EDGE: {
|
||||
// Append the remaining characters of the edge to the key.
|
||||
// For example if we searched for CO, but first matching node was COFFEE,
|
||||
// the key associated with the first node should be COFFEE...
|
||||
CharSequence edgeSuffix = CharSequences.getSuffix(searchResult.nodeFound.getIncomingEdge(), searchResult.charsMatchedInNodeFound);
|
||||
candidate = CharSequences.concatenate(candidate, edgeSuffix);
|
||||
return getDescendantKeyValuePairs(candidate, searchResult.nodeFound);
|
||||
}
|
||||
case INCOMPLETE_MATCH_TO_MIDDLE_OF_EDGE: {
|
||||
// Example: if we searched for CX, but deepest matching node was CO,
|
||||
// the results should include node CO and its descendants...
|
||||
CharSequence keyOfParentNode = CharSequences.getPrefix(candidate, searchResult.charsMatched - searchResult.charsMatchedInNodeFound);
|
||||
CharSequence keyOfNodeFound = CharSequences.concatenate(keyOfParentNode, searchResult.nodeFound.getIncomingEdge());
|
||||
return getDescendantKeyValuePairs(keyOfNodeFound, searchResult.nodeFound);
|
||||
}
|
||||
case INCOMPLETE_MATCH_TO_END_OF_EDGE: {
|
||||
if (searchResult.charsMatched == 0) {
|
||||
// Closest match is the root node, we don't consider this a match for anything...
|
||||
break;
|
||||
}
|
||||
// Example: if we searched for COFFEE, but deepest matching node was CO,
|
||||
// the results should include node CO and its descendants...
|
||||
CharSequence keyOfNodeFound = CharSequences.getPrefix(candidate, searchResult.charsMatched);
|
||||
return getDescendantKeyValuePairs(keyOfNodeFound, searchResult.nodeFound);
|
||||
}
|
||||
}
|
||||
return Collections.emptySet();
|
||||
}
|
||||
|
||||
@Override
|
||||
public int size() {
|
||||
Deque<Node> stack = new LinkedList<>();
|
||||
stack.push(this.root);
|
||||
int count = 0;
|
||||
while (true) {
|
||||
if (stack.isEmpty()) {
|
||||
return count;
|
||||
}
|
||||
Node current = stack.pop();
|
||||
stack.addAll(current.getOutgoingEdges());
|
||||
if (current.getValue() != null) {
|
||||
count++;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Atomically adds the given value to the tree, creating a node for the value as necessary. If the value is already
|
||||
* stored for the same key, either overwrites the existing value, or simply returns the existing value, depending
|
||||
* on the given value of the <code>overwrite</code> flag.
|
||||
*
|
||||
* @param key The key against which the value should be stored
|
||||
* @param value The value to store against the key
|
||||
* @param overwrite If true, should replace any existing value, if false should not replace any existing value
|
||||
* @return The existing value for this key, if there was one, otherwise null
|
||||
*/
|
||||
Object putInternal(CharSequence key, Object value, boolean overwrite) {
|
||||
if (key == null) {
|
||||
throw new IllegalArgumentException("The key argument was null");
|
||||
}
|
||||
if (key.length() == 0) {
|
||||
throw new IllegalArgumentException("The key argument was zero-length");
|
||||
}
|
||||
if (value == null) {
|
||||
throw new IllegalArgumentException("The value argument was null");
|
||||
}
|
||||
acquireWriteLock();
|
||||
try {
|
||||
// Note we search the tree here after we have acquired the write lock...
|
||||
SearchResult searchResult = searchTree(key);
|
||||
SearchResult.Classification classification = searchResult.classification;
|
||||
|
||||
switch (classification) {
|
||||
case EXACT_MATCH: {
|
||||
// Search found an exact match for all edges leading to this node.
|
||||
// -> Add or update the value in the node found, by replacing
|
||||
// the existing node with a new node containing the value...
|
||||
|
||||
// First check if existing node has a value, and if we are allowed to overwrite it.
|
||||
// Return early without overwriting if necessary...
|
||||
Object existingValue = searchResult.nodeFound.getValue();
|
||||
if (!overwrite && existingValue != null) {
|
||||
return existingValue;
|
||||
}
|
||||
// Create a replacement for the existing node containing the new value...
|
||||
Node replacementNode = nodeFactory.createNode(searchResult.nodeFound.getIncomingEdge(), value, searchResult.nodeFound.getOutgoingEdges(), false);
|
||||
searchResult.parentNode.updateOutgoingEdge(replacementNode);
|
||||
// Return the existing value...
|
||||
return existingValue;
|
||||
}
|
||||
case KEY_ENDS_MID_EDGE: {
|
||||
// Search ran out of characters from the key while in the middle of an edge in the node.
|
||||
// -> Split the node in two: Create a new parent node storing the new value,
|
||||
// and a new child node holding the original value and edges from the existing node...
|
||||
CharSequence keyCharsFromStartOfNodeFound = key.subSequence(searchResult.charsMatched - searchResult.charsMatchedInNodeFound, key.length());
|
||||
CharSequence commonPrefix = CharSequences.getCommonPrefix(keyCharsFromStartOfNodeFound, searchResult.nodeFound.getIncomingEdge());
|
||||
CharSequence suffixFromExistingEdge = CharSequences.subtractPrefix(searchResult.nodeFound.getIncomingEdge(), commonPrefix);
|
||||
|
||||
// Create new nodes...
|
||||
Node newChild = nodeFactory.createNode(suffixFromExistingEdge, searchResult.nodeFound.getValue(), searchResult.nodeFound.getOutgoingEdges(), false);
|
||||
Node newParent = nodeFactory.createNode(commonPrefix, value, Collections.singletonList(newChild), false);
|
||||
|
||||
// Add the new parent to the parent of the node being replaced (replacing the existing node)...
|
||||
searchResult.parentNode.updateOutgoingEdge(newParent);
|
||||
|
||||
// Return null for the existing value...
|
||||
return null;
|
||||
}
|
||||
case INCOMPLETE_MATCH_TO_END_OF_EDGE: {
|
||||
// Search found a difference in characters between the key and the start of all child edges leaving the
|
||||
// node, the key still has trailing unmatched characters.
|
||||
// -> Add a new child to the node, containing the trailing characters from the key.
|
||||
|
||||
// NOTE: this is the only branch which allows an edge to be added to the root.
|
||||
// (Root node's own edge is "" empty string, so is considered a prefixing edge of every key)
|
||||
|
||||
// Create a new child node containing the trailing characters...
|
||||
CharSequence keySuffix = key.subSequence(searchResult.charsMatched, key.length());
|
||||
Node newChild = nodeFactory.createNode(keySuffix, value, Collections.emptyList(), false);
|
||||
|
||||
// Clone the current node adding the new child...
|
||||
List<Node> edges = new ArrayList<>(searchResult.nodeFound.getOutgoingEdges().size() + 1);
|
||||
edges.addAll(searchResult.nodeFound.getOutgoingEdges());
|
||||
edges.add(newChild);
|
||||
Node clonedNode = nodeFactory.createNode(searchResult.nodeFound.getIncomingEdge(), searchResult.nodeFound.getValue(), edges, searchResult.nodeFound == root);
|
||||
|
||||
// Re-add the cloned node to its parent node...
|
||||
if (searchResult.nodeFound == root) {
|
||||
this.root = clonedNode;
|
||||
}
|
||||
else {
|
||||
searchResult.parentNode.updateOutgoingEdge(clonedNode);
|
||||
}
|
||||
|
||||
// Return null for the existing value...
|
||||
return null;
|
||||
}
|
||||
case INCOMPLETE_MATCH_TO_MIDDLE_OF_EDGE: {
|
||||
// Search found a difference in characters between the key and the characters in the middle of the
|
||||
// edge in the current node, and the key still has trailing unmatched characters.
|
||||
// -> Split the node in three:
|
||||
// Let's call node found: NF
|
||||
// (1) Create a new node N1 containing the unmatched characters from the rest of the key, and the
|
||||
// value supplied to this method
|
||||
// (2) Create a new node N2 containing the unmatched characters from the rest of the edge in NF, and
|
||||
// copy the original edges and the value from NF unmodified into N2
|
||||
// (3) Create a new node N3, which will be the split node, containing the matched characters from
|
||||
// the key and the edge, and add N1 and N2 as child nodes of N3
|
||||
// (4) Re-add N3 to the parent node of NF, effectively replacing NF in the tree
|
||||
|
||||
CharSequence keyCharsFromStartOfNodeFound = key.subSequence(searchResult.charsMatched - searchResult.charsMatchedInNodeFound, key.length());
|
||||
CharSequence commonPrefix = CharSequences.getCommonPrefix(keyCharsFromStartOfNodeFound, searchResult.nodeFound.getIncomingEdge());
|
||||
CharSequence suffixFromExistingEdge = CharSequences.subtractPrefix(searchResult.nodeFound.getIncomingEdge(), commonPrefix);
|
||||
CharSequence suffixFromKey = key.subSequence(searchResult.charsMatched, key.length());
|
||||
|
||||
// Create new nodes...
|
||||
Node n1 = nodeFactory.createNode(suffixFromKey, value, Collections.emptyList(), false);
|
||||
Node n2 = nodeFactory.createNode(suffixFromExistingEdge, searchResult.nodeFound.getValue(), searchResult.nodeFound.getOutgoingEdges(), false);
|
||||
@SuppressWarnings({"NullableProblems"})
|
||||
Node n3 = nodeFactory.createNode(commonPrefix, null, Arrays.asList(n1, n2), false);
|
||||
|
||||
searchResult.parentNode.updateOutgoingEdge(n3);
|
||||
|
||||
// Return null for the existing value...
|
||||
return null;
|
||||
}
|
||||
default: {
|
||||
// This is a safeguard against a new enum constant being added in future.
|
||||
throw new IllegalStateException("Unexpected classification for search result: " + searchResult);
|
||||
}
|
||||
}
|
||||
}
|
||||
finally {
|
||||
releaseWriteLock();
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Returns a lazy iterable which will return {@link CharSequence} keys for which the given key is a prefix.
|
||||
* The results inherently will not contain duplicates (duplicate keys cannot exist in the tree).
|
||||
* <p/>
|
||||
* Note that this method internally converts {@link CharSequence}s to {@link String}s, to avoid set equality issues,
|
||||
* because equals() and hashCode() are not specified by the CharSequence API contract.
|
||||
*/
|
||||
@SuppressWarnings({"JavaDoc"})
|
||||
Iterable<CharSequence> getDescendantKeys(final CharSequence startKey, final Node startNode) {
|
||||
return () -> new LazyIterator<>() {
|
||||
final Iterator<NodeKeyPair> descendantNodes = lazyTraverseDescendants(startKey, startNode).iterator();
|
||||
|
||||
@Override
|
||||
protected CharSequence computeNext() {
|
||||
// Traverse to the next matching node in the tree and return its key and value...
|
||||
while (descendantNodes.hasNext()) {
|
||||
NodeKeyPair nodeKeyPair = descendantNodes.next();
|
||||
Object value = nodeKeyPair.node.getValue();
|
||||
if (value != null) {
|
||||
// Dealing with a node explicitly added to tree (rather than an automatically-added split node).
|
||||
|
||||
// Call the transformKeyForResult method to allow key to be transformed before returning to client.
|
||||
// Used by subclasses such as ReversedRadixTree implementations...
|
||||
CharSequence optionallyTransformedKey = transformKeyForResult(nodeKeyPair.key);
|
||||
|
||||
// -> Convert the CharSequence to a String before returning, to avoid set equality issues,
|
||||
// because equals() and hashCode() is not specified by the CharSequence API contract...
|
||||
return CharSequences.toString(optionallyTransformedKey);
|
||||
}
|
||||
}
|
||||
// Finished traversing the tree, no more matching nodes to return...
|
||||
return endOfData();
|
||||
}
|
||||
};
|
||||
}
|
||||
|
||||
/**
|
||||
* Returns a lazy iterable which will return values which are associated with keys in the tree for which
|
||||
* the given key is a prefix.
|
||||
*/
|
||||
<O> Iterable<O> getDescendantValues(final CharSequence startKey, final Node startNode) {
|
||||
return () -> new LazyIterator<O>() {
|
||||
final Iterator<NodeKeyPair> descendantNodes = lazyTraverseDescendants(startKey, startNode).iterator();
|
||||
|
||||
@Override
|
||||
protected O computeNext() {
|
||||
// Traverse to the next matching node in the tree and return its key and value...
|
||||
while (descendantNodes.hasNext()) {
|
||||
NodeKeyPair nodeKeyPair = descendantNodes.next();
|
||||
Object value = nodeKeyPair.node.getValue();
|
||||
if (value != null) {
|
||||
// Dealing with a node explicitly added to tree (rather than an automatically-added split node).
|
||||
|
||||
// We have to cast to generic type here, because Node objects are not generically typed.
|
||||
// Background: Node objects are not generically typed, because arrays can't be generically typed,
|
||||
// and we use arrays in nodes. We choose to cast here (in wrapper logic around the tree) rather than
|
||||
// pollute the already-complex tree manipulation logic with casts.
|
||||
@SuppressWarnings({"unchecked", "UnnecessaryLocalVariable"})
|
||||
O valueTyped = (O)value;
|
||||
return valueTyped;
|
||||
}
|
||||
}
|
||||
// Finished traversing the tree, no more matching nodes to return...
|
||||
return endOfData();
|
||||
}
|
||||
};
|
||||
}
|
||||
|
||||
/**
|
||||
* Returns a lazy iterable which will return {@link KeyValuePair} objects each containing a key and a value,
|
||||
* for which the given key is a prefix of the key in the {@link KeyValuePair}. These results inherently will not
|
||||
* contain duplicates (duplicate keys cannot exist in the tree).
|
||||
* <p/>
|
||||
* Note that this method internally converts {@link CharSequence}s to {@link String}s, to avoid set equality issues,
|
||||
* because equals() and hashCode() are not specified by the CharSequence API contract.
|
||||
*/
|
||||
<O> Iterable<KeyValuePair<O>> getDescendantKeyValuePairs(final CharSequence startKey, final Node startNode) {
|
||||
return () -> new LazyIterator<>() {
|
||||
final Iterator<NodeKeyPair> descendantNodes = lazyTraverseDescendants(startKey, startNode).iterator();
|
||||
|
||||
@Override
|
||||
protected KeyValuePair<O> computeNext() {
|
||||
// Traverse to the next matching node in the tree and return its key and value...
|
||||
while (descendantNodes.hasNext()) {
|
||||
NodeKeyPair nodeKeyPair = descendantNodes.next();
|
||||
Object value = nodeKeyPair.node.getValue();
|
||||
if (value != null) {
|
||||
// Dealing with a node explicitly added to tree (rather than an automatically-added split node).
|
||||
|
||||
// Call the transformKeyForResult method to allow key to be transformed before returning to client.
|
||||
// Used by subclasses such as ReversedRadixTree implementations...
|
||||
CharSequence optionallyTransformedKey = transformKeyForResult(nodeKeyPair.key);
|
||||
|
||||
// -> Convert the CharSequence to a String before returning, to avoid set equality issues,
|
||||
// because equals() and hashCode() is not specified by the CharSequence API contract...
|
||||
String keyString = CharSequences.toString(optionallyTransformedKey);
|
||||
return new KeyValuePairImpl<>(keyString, value);
|
||||
}
|
||||
}
|
||||
// Finished traversing the tree, no more matching nodes to return...
|
||||
return endOfData();
|
||||
}
|
||||
};
|
||||
}
|
||||
|
||||
/**
|
||||
* Implementation of the {@link KeyValuePair} interface.
|
||||
*/
|
||||
public static class KeyValuePairImpl<O> implements KeyValuePair<O> {
|
||||
|
||||
final String key;
|
||||
final O value;
|
||||
|
||||
/**
|
||||
* Constructor.
|
||||
*
|
||||
* Implementation node: This constructor currently requires the key to be supplied as a {@link String}
|
||||
* - this is to allow reliable testing of object equality; the alternative {@link CharSequence}
|
||||
* does not specify a contract for {@link Object#equals(Object)}.
|
||||
*
|
||||
* @param key The key as a string
|
||||
* @param value The value
|
||||
*/
|
||||
public KeyValuePairImpl(String key, Object value) {
|
||||
this.key = key;
|
||||
// We have to cast to generic type here, because Node objects are not generically typed.
|
||||
// Background: Node objects are not generically typed, because arrays can't be generically typed,
|
||||
// and we use arrays in nodes. We choose to cast here (in wrapper logic around the tree) rather than
|
||||
// pollute the already-complex tree manipulation logic with casts.
|
||||
@SuppressWarnings({"unchecked", "UnnecessaryLocalVariable"})
|
||||
O valueTyped = (O)value;
|
||||
this.value = valueTyped;
|
||||
}
|
||||
|
||||
@Override
|
||||
public CharSequence getKey() {
|
||||
return key;
|
||||
}
|
||||
|
||||
@Override
|
||||
public O getValue() {
|
||||
return value;
|
||||
}
|
||||
|
||||
@Override
|
||||
public boolean equals(Object o) {
|
||||
if (this == o) {
|
||||
return true;
|
||||
}
|
||||
if (o == null || getClass() != o.getClass()) {
|
||||
return false;
|
||||
}
|
||||
KeyValuePairImpl<?> that = (KeyValuePairImpl<?>) o;
|
||||
return key.equals(that.key);
|
||||
|
||||
}
|
||||
|
||||
@Override
|
||||
public int hashCode() {
|
||||
return key.hashCode();
|
||||
}
|
||||
|
||||
@Override
|
||||
public String toString() {
|
||||
return "(" + key + ", " + value + ")";
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Traverses the tree using depth-first, preordered traversal, starting at the given node, using lazy evaluation
|
||||
* such that the next node is only determined when next() is called on the iterator returned.
|
||||
* The traversal algorithm uses iteration instead of recursion to allow deep trees to be traversed without
|
||||
* requiring large JVM stack sizes.
|
||||
* <p/>
|
||||
* Each node that is encountered is returned from the iterator along with a key associated with that node,
|
||||
* in a NodeKeyPair object. The key will be prefixed by the given start key, and will be generated by appending
|
||||
* to the start key the edges traversed along the path to that node from the start node.
|
||||
*
|
||||
* @param startKey The key which matches the given start node
|
||||
* @param startNode The start node
|
||||
* @return An iterator which when iterated traverses the tree using depth-first, preordered traversal,
|
||||
* starting at the given start node
|
||||
*/
|
||||
protected Iterable<NodeKeyPair> lazyTraverseDescendants(final CharSequence startKey, final Node startNode) {
|
||||
return () -> new LazyIterator<>() {
|
||||
final Deque<NodeKeyPair> stack = new LinkedList<>();
|
||||
{
|
||||
stack.push(new NodeKeyPair(startNode, startKey));
|
||||
}
|
||||
|
||||
@Override
|
||||
protected NodeKeyPair computeNext() {
|
||||
if (stack.isEmpty()) {
|
||||
return endOfData();
|
||||
}
|
||||
NodeKeyPair current = stack.pop();
|
||||
List<Node> childNodes = current.node.getOutgoingEdges();
|
||||
|
||||
// -> Iterate child nodes in reverse order and so push them onto the stack in reverse order,
|
||||
// to counteract that pushing them onto the stack alone would otherwise reverse their processing order.
|
||||
// This ensures that we actually process nodes in ascending alphabetical order.
|
||||
for (int i = childNodes.size(); i > 0; i--) {
|
||||
Node child = childNodes.get(i - 1);
|
||||
stack.push(new NodeKeyPair(child, CharSequences.concatenate(current.key, child.getIncomingEdge())));
|
||||
}
|
||||
return current;
|
||||
}
|
||||
};
|
||||
}
|
||||
|
||||
|
||||
/**
|
||||
* Encapsulates a node and its associated key. Used internally by {@link #lazyTraverseDescendants}.
|
||||
*/
|
||||
protected static class NodeKeyPair {
|
||||
public final Node node;
|
||||
public final CharSequence key;
|
||||
|
||||
public NodeKeyPair(Node node, CharSequence key) {
|
||||
this.node = node;
|
||||
this.key = key;
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* A hook method which may be overridden by subclasses, to transform a key just before it is returned to
|
||||
* the application, for example by the {@link #getKeysStartingWith(CharSequence)} or the
|
||||
* {@link #getKeyValuePairsForKeysStartingWith(CharSequence)} methods.
|
||||
* <p/>
|
||||
* This hook is expected to be used by
|
||||
* implementations where keys are stored in the tree in reverse order but results should be returned in normal
|
||||
* order.
|
||||
* <p/>
|
||||
* <b>This default implementation simply returns the given key unmodified.</b>
|
||||
*
|
||||
* @param rawKey The raw key as stored in the tree
|
||||
* @return A transformed version of the key
|
||||
*/
|
||||
protected CharSequence transformKeyForResult(CharSequence rawKey) {
|
||||
return rawKey;
|
||||
}
|
||||
|
||||
|
||||
/**
|
||||
* Traverses the tree and finds the node which matches the longest prefix of the given key.
|
||||
* <p/>
|
||||
* The node returned might be an <u>exact match</u> for the key, in which case {@link SearchResult#charsMatched}
|
||||
* will equal the length of the key.
|
||||
* <p/>
|
||||
* The node returned might be an <u>inexact match</u> for the key, in which case {@link SearchResult#charsMatched}
|
||||
* will be less than the length of the key.
|
||||
* <p/>
|
||||
* There are two types of inexact match:
|
||||
* <ul>
|
||||
* <li>
|
||||
* An inexact match which ends evenly at the boundary between a node and its children (the rest of the key
|
||||
* not matching any children at all). In this case if we we wanted to add nodes to the tree to represent the
|
||||
* rest of the key, we could simply add child nodes to the node found.
|
||||
* </li>
|
||||
* <li>
|
||||
* An inexact match which ends in the middle of a the characters for an edge stored in a node (the key
|
||||
* matching only the first few characters of the edge). In this case if we we wanted to add nodes to the
|
||||
* tree to represent the rest of the key, we would have to split the node (let's call this node found: NF):
|
||||
* <ol>
|
||||
* <li>
|
||||
* Create a new node (N1) which will be the split node, containing the matched characters from the
|
||||
* start of the edge in NF
|
||||
* </li>
|
||||
* <li>
|
||||
* Create a new node (N2) which will contain the unmatched characters from the rest of the edge
|
||||
* in NF, and copy the original edges from NF unmodified into N2
|
||||
* </li>
|
||||
* <li>
|
||||
* Create a new node (N3) which will be the new branch, containing the unmatched characters from
|
||||
* the rest of the key
|
||||
* </li>
|
||||
* <li>
|
||||
* Add N2 as a child of N1
|
||||
* </li>
|
||||
* <li>
|
||||
* Add N3 as a child of N1
|
||||
* </li>
|
||||
* <li>
|
||||
* In the <b>parent node of NF</b>, replace the edge pointing to NF with an edge pointing instead
|
||||
* to N1. If we do this step atomically, reading threads are guaranteed to never see "invalid"
|
||||
* data, only either the old data or the new data
|
||||
* </li>
|
||||
* </ol>
|
||||
* </li>
|
||||
* </ul>
|
||||
* The {@link SearchResult#classification} is an enum value based on its classification of the
|
||||
* match according to the descriptions above.
|
||||
*
|
||||
* @param key a key for which the node matching the longest prefix of the key is required
|
||||
* @return A {@link SearchResult} object which contains the node matching the longest prefix of the key, its
|
||||
* parent node, the number of characters of the key which were matched in total and within the edge of the
|
||||
* matched node, and a {@link SearchResult#classification} of the match as described above
|
||||
*/
|
||||
SearchResult searchTree(CharSequence key) {
|
||||
Node parentNodesParent = null;
|
||||
Node parentNode = null;
|
||||
Node currentNode = root;
|
||||
int charsMatched = 0, charsMatchedInNodeFound = 0;
|
||||
|
||||
final int keyLength = key.length();
|
||||
outer_loop: while (charsMatched < keyLength) {
|
||||
Node nextNode = currentNode.getOutgoingEdge(key.charAt(charsMatched));
|
||||
if (nextNode == null) {
|
||||
// Next node is a dead end...
|
||||
//noinspection UnnecessaryLabelOnBreakStatement
|
||||
break outer_loop;
|
||||
}
|
||||
|
||||
parentNodesParent = parentNode;
|
||||
parentNode = currentNode;
|
||||
currentNode = nextNode;
|
||||
charsMatchedInNodeFound = 0;
|
||||
CharSequence currentNodeEdgeCharacters = currentNode.getIncomingEdge();
|
||||
for (int i = 0, numEdgeChars = currentNodeEdgeCharacters.length(); i < numEdgeChars && charsMatched < keyLength; i++) {
|
||||
if (currentNodeEdgeCharacters.charAt(i) != key.charAt(charsMatched)) {
|
||||
// Found a difference in chars between character in key and a character in current node.
|
||||
// Current node is the deepest match (inexact match)....
|
||||
break outer_loop;
|
||||
}
|
||||
charsMatched++;
|
||||
charsMatchedInNodeFound++;
|
||||
}
|
||||
}
|
||||
return new SearchResult(key, currentNode, charsMatched, charsMatchedInNodeFound, parentNode, parentNodesParent);
|
||||
}
|
||||
|
||||
/**
|
||||
* Encapsulates results of searching the tree for a node for which a given key is a prefix. Encapsulates the node
|
||||
* found, its parent node, its parent's parent node, and the number of characters matched in the current node and
|
||||
* in total.
|
||||
* <p/>
|
||||
* Also classifies the search result so that algorithms in methods which use this SearchResult, when adding nodes
|
||||
* and removing nodes from the tree, can select appropriate strategies based on the classification.
|
||||
*/
|
||||
static class SearchResult {
|
||||
final CharSequence key;
|
||||
final Node nodeFound;
|
||||
final int charsMatched;
|
||||
final int charsMatchedInNodeFound;
|
||||
final Node parentNode;
|
||||
final Node parentNodesParent;
|
||||
final Classification classification;
|
||||
|
||||
enum Classification {
|
||||
EXACT_MATCH,
|
||||
INCOMPLETE_MATCH_TO_END_OF_EDGE,
|
||||
INCOMPLETE_MATCH_TO_MIDDLE_OF_EDGE,
|
||||
KEY_ENDS_MID_EDGE,
|
||||
INVALID // INVALID is never used, except in unit testing
|
||||
}
|
||||
|
||||
SearchResult(CharSequence key, Node nodeFound, int charsMatched, int charsMatchedInNodeFound, Node parentNode, Node parentNodesParent) {
|
||||
this.key = key;
|
||||
this.nodeFound = nodeFound;
|
||||
this.charsMatched = charsMatched;
|
||||
this.charsMatchedInNodeFound = charsMatchedInNodeFound;
|
||||
this.parentNode = parentNode;
|
||||
this.parentNodesParent = parentNodesParent;
|
||||
|
||||
// Classify this search result...
|
||||
this.classification = classify(key, nodeFound, charsMatched, charsMatchedInNodeFound);
|
||||
}
|
||||
|
||||
protected Classification classify(CharSequence key, Node nodeFound, int charsMatched, int charsMatchedInNodeFound) {
|
||||
if (charsMatched == key.length()) {
|
||||
if (charsMatchedInNodeFound == nodeFound.getIncomingEdge().length()) {
|
||||
return Classification.EXACT_MATCH;
|
||||
}
|
||||
else if (charsMatchedInNodeFound < nodeFound.getIncomingEdge().length()) {
|
||||
return Classification.KEY_ENDS_MID_EDGE;
|
||||
}
|
||||
}
|
||||
else if (charsMatched < key.length()) {
|
||||
if (charsMatchedInNodeFound == nodeFound.getIncomingEdge().length()) {
|
||||
return Classification.INCOMPLETE_MATCH_TO_END_OF_EDGE;
|
||||
}
|
||||
else if (charsMatchedInNodeFound < nodeFound.getIncomingEdge().length()) {
|
||||
return Classification.INCOMPLETE_MATCH_TO_MIDDLE_OF_EDGE;
|
||||
}
|
||||
}
|
||||
throw new IllegalStateException("Unexpected failure to classify SearchResult: " + this);
|
||||
}
|
||||
|
||||
@Override
|
||||
public String toString() {
|
||||
return "SearchResult{" +
|
||||
"key=" + key +
|
||||
", nodeFound=" + nodeFound +
|
||||
", charsMatched=" + charsMatched +
|
||||
", charsMatchedInNodeFound=" + charsMatchedInNodeFound +
|
||||
", parentNode=" + parentNode +
|
||||
", parentNodesParent=" + parentNodesParent +
|
||||
", classification=" + classification +
|
||||
'}';
|
||||
}
|
||||
}
|
||||
|
||||
public Node getNode() {
|
||||
return root;
|
||||
}
|
||||
|
||||
}
|
||||
@ -0,0 +1,145 @@
|
||||
package org.xbib.datastructures.trie.concurrent;
|
||||
|
||||
import org.xbib.datastructures.trie.concurrent.util.KeyValuePair;
|
||||
|
||||
/**
|
||||
* API of a radix tree, that is a tree which allows values to be looked up based on <i>prefixes</i> of the keys
|
||||
* with which they were associated, as well as based on exact matches for keys. A radix tree essentially allows
|
||||
* <i><u>"equals"</u></i> and <i><u>"starts with"</u></i> lookup.
|
||||
* <p/>
|
||||
* See documentation on each method for details.
|
||||
*
|
||||
* @param <O> The type of the values associated with keys in the tree
|
||||
*/
|
||||
public interface RadixTree<O> {
|
||||
|
||||
/**
|
||||
* Associates the given value with the given key; replacing any previous value associated with the key.
|
||||
* Returns the previous value associated with the key, if any.
|
||||
* <p/>
|
||||
* This operation is performed atomically.
|
||||
*
|
||||
* @param key The key with which the specified value should be associated
|
||||
* @param value The value to associate with the key, which cannot be null
|
||||
* @return The previous value associated with the key, if there was one, otherwise null
|
||||
*/
|
||||
O put(CharSequence key, O value);
|
||||
|
||||
/**
|
||||
* If a value is not already associated with the given key in the tree, associates the given value with the
|
||||
* key; otherwise if an existing value is already associated, returns the existing value and does not overwrite it.
|
||||
* <p/>
|
||||
* This operation is performed atomically.
|
||||
*
|
||||
* @param key The key with which the specified value should be associated
|
||||
* @param value The value to associate with the key, which cannot be null
|
||||
* @return The existing value associated with the key, if there was one; otherwise null in which case the new
|
||||
* value was successfully associated
|
||||
*/
|
||||
O putIfAbsent(CharSequence key, O value);
|
||||
|
||||
/**
|
||||
* Removes the value associated with the given key (exact match).
|
||||
* If no value is associated with the key, does nothing.
|
||||
*
|
||||
* @param key The key for which an associated value should be removed
|
||||
* @return True if a value was removed (and therefore was associated with the key), false if no value was
|
||||
* associated/removed
|
||||
*/
|
||||
boolean remove(CharSequence key);
|
||||
|
||||
/**
|
||||
* Returns the value associated with the given key (exact match), or returns null if no such value
|
||||
* is associated with the key.
|
||||
*
|
||||
* @param key The key with which a sought value might be associated
|
||||
* @return The value associated with the given key (exact match), or null if no value was associated with the key
|
||||
*/
|
||||
O getValueForExactKey(CharSequence key);
|
||||
|
||||
/**
|
||||
* Returns a lazy iterable which returns the set of keys in the tree which start with the given prefix.
|
||||
* <p/>
|
||||
* This is <i>inclusive</i> - if the given prefix is an exact match for a key in the tree, that key is also
|
||||
* returned.
|
||||
*
|
||||
* @param prefix A prefix of sought keys in the tree
|
||||
* @return The set of keys in the tree which start with the given prefix, inclusive
|
||||
*/
|
||||
Iterable<CharSequence> getKeysStartingWith(CharSequence prefix);
|
||||
|
||||
/**
|
||||
* Returns a lazy iterable which returns the set of values associated with keys in the tree which start with the
|
||||
* given prefix.
|
||||
* <p/>
|
||||
* This is <i>inclusive</i> - if the given prefix is an exact match for a key in the tree, the value associated
|
||||
* with that key is also returned.
|
||||
* <p/>
|
||||
* Note that although the same value might originally have been associated with multiple keys, the set returned
|
||||
* does not contain duplicates (as determined by the value objects' implementation of {@link Object#equals(Object)}).
|
||||
*
|
||||
* @param prefix A prefix of keys in the tree for which associated values are sought
|
||||
* @return The set of values associated with keys in the tree which start with the given prefix, inclusive
|
||||
*/
|
||||
Iterable<O> getValuesForKeysStartingWith(CharSequence prefix);
|
||||
|
||||
/**
|
||||
* Returns a lazy iterable which returns the set of {@link KeyValuePair}s for keys and their associated values
|
||||
* in the tree, where the keys start with the given prefix.
|
||||
* <p/>
|
||||
* This is <i>inclusive</i> - if the given prefix is an exact match for a key in the tree, the {@link KeyValuePair}
|
||||
* for that key is also returned.
|
||||
*
|
||||
* @param prefix A prefix of keys in the tree for which associated {@link KeyValuePair}s are sought
|
||||
* @return The set of {@link KeyValuePair}s for keys in the tree which start with the given prefix, inclusive
|
||||
*/
|
||||
Iterable<KeyValuePair<O>> getKeyValuePairsForKeysStartingWith(CharSequence prefix);
|
||||
|
||||
/**
|
||||
* Returns a lazy iterable which returns the set of keys in the tree which are the closest match for the given
|
||||
* candidate key.
|
||||
* <p/>
|
||||
* Example:<br/>
|
||||
* Tree contains: {@code Ford Focus}, {@code Ford Mondeo}, {@code BMW M3}<br/>
|
||||
* <code>getClosestKeys("Ford F150")</code> -> returns {@code Ford Focus}, {@code Ford Mondeo}<br/>
|
||||
* <p/>
|
||||
* This is <i>inclusive</i> - if the given candidate is an exact match for a key in the tree, that key is also
|
||||
* returned.
|
||||
*
|
||||
* @param candidate A candidate key
|
||||
* @return The set of keys in the tree which most closely match the candidate key, inclusive
|
||||
*/
|
||||
Iterable<CharSequence> getClosestKeys(CharSequence candidate);
|
||||
|
||||
/**
|
||||
* Returns a lazy iterable which returns the set of values associated with keys in the tree which are the closest
|
||||
* match for the given candidate key.
|
||||
* <p/>
|
||||
* See {#getClosestKeys} for more details.
|
||||
*
|
||||
* @param candidate A candidate key
|
||||
* @return The set of values associated with keys in the tree which most closely match the candidate key, inclusive
|
||||
*/
|
||||
Iterable<O> getValuesForClosestKeys(CharSequence candidate);
|
||||
|
||||
/**
|
||||
* Returns a lazy iterable which returns the set of {@link KeyValuePair}s for keys and their associated values in
|
||||
* the tree which are the closest match for the given candidate key.
|
||||
* <p/>
|
||||
* See {#getClosestKeys} for more details.
|
||||
*
|
||||
* @param candidate A candidate key
|
||||
* @return The set of {@link KeyValuePair}s for keys and their associated values in the tree which most closely
|
||||
* match the candidate key, inclusive
|
||||
*/
|
||||
Iterable<KeyValuePair<O>> getKeyValuePairsForClosestKeys(CharSequence candidate);
|
||||
|
||||
/**
|
||||
* Counts the number of keys/values stored in the tree.
|
||||
* <p/>
|
||||
* In the current implementation, <b>this is an expensive operation</b>, having O(n) time complexity.
|
||||
*
|
||||
* @return The number of keys/values stored in the tree
|
||||
*/
|
||||
int size();
|
||||
}
|
||||
@ -0,0 +1,30 @@
|
||||
package org.xbib.datastructures.trie.concurrent.util;
|
||||
|
||||
import java.util.AbstractList;
|
||||
import java.util.concurrent.atomic.AtomicReferenceArray;
|
||||
|
||||
/**
|
||||
* Wraps an {@link AtomicReferenceArray} to implement read-only methods of the {@link java.util.List} interface.
|
||||
* <p/>
|
||||
* This enables binary search of an {@link AtomicReferenceArray}, using
|
||||
* {@link java.util.Collections#binarySearch(java.util.List, Object)}.
|
||||
*/
|
||||
@SuppressWarnings("serial")
|
||||
public class AtomicReferenceArrayListAdapter<T> extends AbstractList<T> {
|
||||
|
||||
private final AtomicReferenceArray<T> atomicReferenceArray;
|
||||
|
||||
public AtomicReferenceArrayListAdapter(AtomicReferenceArray<T> atomicReferenceArray) {
|
||||
this.atomicReferenceArray = atomicReferenceArray;
|
||||
}
|
||||
|
||||
@Override
|
||||
public T get(int index) {
|
||||
return atomicReferenceArray.get(index);
|
||||
}
|
||||
|
||||
@Override
|
||||
public int size() {
|
||||
return atomicReferenceArray.length();
|
||||
}
|
||||
}
|
||||
@ -0,0 +1,117 @@
|
||||
package org.xbib.datastructures.trie.concurrent.util;
|
||||
|
||||
import java.util.Arrays;
|
||||
import java.util.List;
|
||||
import java.util.concurrent.atomic.AtomicReferenceArray;
|
||||
|
||||
/**
|
||||
* A non-optimized implementation of the {@link Node} interface. Stores all variables and supports all behaviours
|
||||
* required by the tree, but not very memory efficient.
|
||||
* <p/>
|
||||
* See {@link NodeFactory} for documentation on how alternative
|
||||
* node implementations can be created to reduce memory overhead. See the {@link Node} interface for details on how
|
||||
* to write memory-efficient nodes.
|
||||
* <p/>
|
||||
* This implementation stores references to child nodes in an {@link AtomicReferenceArray}, in ascending sorted order
|
||||
* of the first character of the edges which child nodes define.
|
||||
* <p/>
|
||||
* The {@link #getOutgoingEdge(Character)} method uses binary search to locate a requested node, given the first character
|
||||
* of an edge indicated. The node is then read and returned atomically from the {@link AtomicReferenceArray}.
|
||||
* <p/>
|
||||
* The {@link #updateOutgoingEdge(Node)} method ensures that any
|
||||
* attempt to update a reference to a child node preserves the constraints defined in the {@link Node} interface. New
|
||||
* child nodes are written atomically to the {@link AtomicReferenceArray}.
|
||||
* <p/>
|
||||
* The constraints defined in the {@link Node} interface ensure that the {@link AtomicReferenceArray} always remains in
|
||||
* ascending sorted order regardless of modifications performed concurrently, as long as the modifications comply with
|
||||
* the constraints. This node enforces those constraints.
|
||||
*
|
||||
* @author Niall Gallagher
|
||||
*/
|
||||
public class CharArrayNodeDefault implements Node {
|
||||
|
||||
|
||||
// Characters in the edge arriving at this node from a parent node.
|
||||
// Once assigned, we never modify this...
|
||||
private final char[] incomingEdgeCharArray;
|
||||
|
||||
// References to child nodes representing outgoing edges from this node.
|
||||
// Once assigned we never add or remove references, but we do update existing references to point to new child
|
||||
// nodes provided new edges start with the same first character...
|
||||
private final AtomicReferenceArray<Node> outgoingEdges;
|
||||
|
||||
// A read-only List wrapper around the outgoingEdges AtomicReferenceArray...
|
||||
private final List<Node> outgoingEdgesAsList;
|
||||
|
||||
// An arbitrary value which the application associates with a key matching the path to this node in the tree.
|
||||
// This value can be null...
|
||||
private final Object value;
|
||||
|
||||
public CharArrayNodeDefault(CharSequence edgeCharSequence, Object value, List<Node> outgoingEdges) {
|
||||
Node[] childNodeArray = outgoingEdges.toArray(new Node[outgoingEdges.size()]);
|
||||
// Sort the child nodes...
|
||||
Arrays.sort(childNodeArray, new NodeCharacterComparator());
|
||||
this.outgoingEdges = new AtomicReferenceArray<Node>(childNodeArray);
|
||||
this.incomingEdgeCharArray = CharSequences.toCharArray(edgeCharSequence);
|
||||
this.value = value;
|
||||
this.outgoingEdgesAsList = new AtomicReferenceArrayListAdapter<Node>(this.outgoingEdges);
|
||||
}
|
||||
|
||||
@Override
|
||||
public CharSequence getIncomingEdge() {
|
||||
return CharSequences.fromCharArray(incomingEdgeCharArray);
|
||||
}
|
||||
|
||||
@Override
|
||||
public Character getIncomingEdgeFirstCharacter() {
|
||||
return incomingEdgeCharArray[0];
|
||||
}
|
||||
|
||||
@Override
|
||||
public Object getValue() {
|
||||
return value;
|
||||
}
|
||||
|
||||
@Override
|
||||
public Node getOutgoingEdge(Character edgeFirstCharacter) {
|
||||
// Binary search for the index of the node whose edge starts with the given character.
|
||||
// Note that this binary search is safe in the face of concurrent modification due to constraints
|
||||
// we enforce on use of the array, as documented in the binarySearchForEdge method...
|
||||
int index = NodeUtil.binarySearchForEdge(outgoingEdges, edgeFirstCharacter);
|
||||
if (index < 0) {
|
||||
// No such edge exists...
|
||||
return null;
|
||||
}
|
||||
// Atomically return the child node at this index...
|
||||
return outgoingEdges.get(index);
|
||||
}
|
||||
|
||||
@Override
|
||||
public void updateOutgoingEdge(Node childNode) {
|
||||
// Binary search for the index of the node whose edge starts with the given character.
|
||||
// Note that this binary search is safe in the face of concurrent modification due to constraints
|
||||
// we enforce on use of the array, as documented in the binarySearchForEdge method...
|
||||
int index = NodeUtil.binarySearchForEdge(outgoingEdges, childNode.getIncomingEdgeFirstCharacter());
|
||||
if (index < 0) {
|
||||
throw new IllegalStateException("Cannot update the reference to the following child node for the edge starting with '" + childNode.getIncomingEdgeFirstCharacter() +"', no such edge already exists: " + childNode);
|
||||
}
|
||||
// Atomically update the child node at this index...
|
||||
outgoingEdges.set(index, childNode);
|
||||
}
|
||||
|
||||
@Override
|
||||
public List<Node> getOutgoingEdges() {
|
||||
return outgoingEdgesAsList;
|
||||
}
|
||||
|
||||
@Override
|
||||
public String toString() {
|
||||
StringBuilder sb = new StringBuilder();
|
||||
sb.append("Node{");
|
||||
sb.append("edge=").append(incomingEdgeCharArray);
|
||||
sb.append(", value=").append(value);
|
||||
sb.append(", edges=").append(getOutgoingEdges());
|
||||
sb.append("}");
|
||||
return sb.toString();
|
||||
}
|
||||
}
|
||||
@ -0,0 +1,61 @@
|
||||
package org.xbib.datastructures.trie.concurrent.util;
|
||||
|
||||
import java.util.Collections;
|
||||
import java.util.List;
|
||||
|
||||
/**
|
||||
* Stores only incoming edge as a {@code char[]}.
|
||||
* Returns {@code null} for the value. Does <b>not</b> store any outgoing edges.
|
||||
*/
|
||||
public class CharArrayNodeLeafNullValue implements Node {
|
||||
|
||||
|
||||
// Characters in the edge arriving at this node from a parent node.
|
||||
// Once assigned, we never modify this...
|
||||
private final char[] incomingEdgeCharArray;
|
||||
|
||||
public CharArrayNodeLeafNullValue(CharSequence edgeCharSequence) {
|
||||
this.incomingEdgeCharArray = CharSequences.toCharArray(edgeCharSequence);
|
||||
}
|
||||
|
||||
@Override
|
||||
public CharSequence getIncomingEdge() {
|
||||
return CharSequences.fromCharArray(incomingEdgeCharArray);
|
||||
}
|
||||
|
||||
@Override
|
||||
public Character getIncomingEdgeFirstCharacter() {
|
||||
return incomingEdgeCharArray[0];
|
||||
}
|
||||
|
||||
@Override
|
||||
public Object getValue() {
|
||||
return null;
|
||||
}
|
||||
|
||||
@Override
|
||||
public Node getOutgoingEdge(Character edgeFirstCharacter) {
|
||||
return null;
|
||||
}
|
||||
|
||||
@Override
|
||||
public void updateOutgoingEdge(Node childNode) {
|
||||
throw new IllegalStateException("Cannot update the reference to the following child node for the edge starting with '" + childNode.getIncomingEdgeFirstCharacter() +"', no such edge already exists: " + childNode);
|
||||
}
|
||||
|
||||
@Override
|
||||
public List<Node> getOutgoingEdges() {
|
||||
return Collections.emptyList();
|
||||
}
|
||||
|
||||
@Override
|
||||
public String toString() {
|
||||
StringBuilder sb = new StringBuilder();
|
||||
sb.append("Node{");
|
||||
sb.append("edge=").append(incomingEdgeCharArray);
|
||||
sb.append(", value=null");
|
||||
sb.append(", edges=[]");
|
||||
sb.append("}");
|
||||
return sb.toString();
|
||||
}
|
||||
}
|
||||
@ -0,0 +1,60 @@
|
||||
package org.xbib.datastructures.trie.concurrent.util;
|
||||
|
||||
import java.util.Collections;
|
||||
import java.util.List;
|
||||
|
||||
/**
|
||||
* Stores only incoming edge as a {@code char[]}.
|
||||
* Returns {@link VoidValue} for the value. Does <b>not</b> store any outgoing edges.
|
||||
*/
|
||||
public class CharArrayNodeLeafVoidValue implements Node {
|
||||
|
||||
// Characters in the edge arriving at this node from a parent node.
|
||||
// Once assigned, we never modify this...
|
||||
private final char[] incomingEdgeCharArray;
|
||||
|
||||
public CharArrayNodeLeafVoidValue(CharSequence edgeCharSequence) {
|
||||
this.incomingEdgeCharArray = CharSequences.toCharArray(edgeCharSequence);
|
||||
}
|
||||
|
||||
@Override
|
||||
public CharSequence getIncomingEdge() {
|
||||
return CharSequences.fromCharArray(incomingEdgeCharArray);
|
||||
}
|
||||
|
||||
@Override
|
||||
public Character getIncomingEdgeFirstCharacter() {
|
||||
return incomingEdgeCharArray[0];
|
||||
}
|
||||
|
||||
@Override
|
||||
public Object getValue() {
|
||||
return VoidValue.SINGLETON;
|
||||
}
|
||||
|
||||
@Override
|
||||
public Node getOutgoingEdge(Character edgeFirstCharacter) {
|
||||
return null;
|
||||
}
|
||||
|
||||
@Override
|
||||
public void updateOutgoingEdge(Node childNode) {
|
||||
throw new IllegalStateException("Cannot update the reference to the following child node for the edge starting with '" + childNode.getIncomingEdgeFirstCharacter() +"', no such edge already exists: " + childNode);
|
||||
}
|
||||
|
||||
@Override
|
||||
public List<Node> getOutgoingEdges() {
|
||||
return Collections.emptyList();
|
||||
}
|
||||
|
||||
@Override
|
||||
public String toString() {
|
||||
StringBuilder sb = new StringBuilder();
|
||||
sb.append("Node{");
|
||||
sb.append("edge=").append(incomingEdgeCharArray);
|
||||
sb.append(", value=").append(VoidValue.SINGLETON);
|
||||
sb.append(", edges=[]");
|
||||
sb.append("}");
|
||||
return sb.toString();
|
||||
}
|
||||
}
|
||||
@ -0,0 +1,66 @@
|
||||
package org.xbib.datastructures.trie.concurrent.util;
|
||||
|
||||
import java.util.Collections;
|
||||
import java.util.List;
|
||||
|
||||
/**
|
||||
* Stores only incoming edge as a {@code char[]}, and a reference to a value. Does <b>not</b> store any outgoing
|
||||
* edges.
|
||||
*/
|
||||
public class CharArrayNodeLeafWithValue implements Node {
|
||||
|
||||
|
||||
// Characters in the edge arriving at this node from a parent node.
|
||||
// Once assigned, we never modify this...
|
||||
private final char[] incomingEdgeCharArray;
|
||||
|
||||
// An arbitrary value which the application associates with a key matching the path to this node in the tree.
|
||||
// This value can be null...
|
||||
private final Object value;
|
||||
|
||||
public CharArrayNodeLeafWithValue(CharSequence edgeCharSequence, Object value) {
|
||||
this.incomingEdgeCharArray = CharSequences.toCharArray(edgeCharSequence);
|
||||
this.value = value;
|
||||
}
|
||||
|
||||
@Override
|
||||
public CharSequence getIncomingEdge() {
|
||||
return CharSequences.fromCharArray(incomingEdgeCharArray);
|
||||
}
|
||||
|
||||
@Override
|
||||
public Character getIncomingEdgeFirstCharacter() {
|
||||
return incomingEdgeCharArray[0];
|
||||
}
|
||||
|
||||
@Override
|
||||
public Object getValue() {
|
||||
return value;
|
||||
}
|
||||
|
||||
@Override
|
||||
public Node getOutgoingEdge(Character edgeFirstCharacter) {
|
||||
return null;
|
||||
}
|
||||
|
||||
@Override
|
||||
public void updateOutgoingEdge(Node childNode) {
|
||||
throw new IllegalStateException("Cannot update the reference to the following child node for the edge starting with '" + childNode.getIncomingEdgeFirstCharacter() +"', no such edge already exists: " + childNode);
|
||||
}
|
||||
|
||||
@Override
|
||||
public List<Node> getOutgoingEdges() {
|
||||
return Collections.emptyList();
|
||||
}
|
||||
|
||||
@Override
|
||||
public String toString() {
|
||||
StringBuilder sb = new StringBuilder();
|
||||
sb.append("Node{");
|
||||
sb.append("edge=").append(incomingEdgeCharArray);
|
||||
sb.append(", value=").append(value);
|
||||
sb.append(", edges=[]");
|
||||
sb.append("}");
|
||||
return sb.toString();
|
||||
}
|
||||
}
|
||||
@ -0,0 +1,92 @@
|
||||
package org.xbib.datastructures.trie.concurrent.util;
|
||||
|
||||
import java.util.Arrays;
|
||||
import java.util.List;
|
||||
import java.util.concurrent.atomic.AtomicReferenceArray;
|
||||
|
||||
/**
|
||||
* Stores incoming edge as a {@code char[]} and outgoing edges as an {@link AtomicReferenceArray}. Does not store a
|
||||
* value and returns {@code null} for the value.
|
||||
*/
|
||||
public class CharArrayNodeNonLeafNullValue implements Node {
|
||||
|
||||
|
||||
// Characters in the edge arriving at this node from a parent node.
|
||||
// Once assigned, we never modify this...
|
||||
private final char[] incomingEdgeCharArray;
|
||||
|
||||
// References to child nodes representing outgoing edges from this node.
|
||||
// Once assigned we never add or remove references, but we do update existing references to point to new child
|
||||
// nodes provided new edges start with the same first character...
|
||||
private final AtomicReferenceArray<Node> outgoingEdges;
|
||||
|
||||
// A read-only List wrapper around the outgoingEdges AtomicReferenceArray...
|
||||
private final List<Node> outgoingEdgesAsList;
|
||||
|
||||
public CharArrayNodeNonLeafNullValue(CharSequence edgeCharSequence, List<Node> outgoingEdges) {
|
||||
Node[] childNodeArray = outgoingEdges.toArray(new Node[outgoingEdges.size()]);
|
||||
// Sort the child nodes...
|
||||
Arrays.sort(childNodeArray, new NodeCharacterComparator());
|
||||
this.outgoingEdges = new AtomicReferenceArray<Node>(childNodeArray);
|
||||
this.incomingEdgeCharArray = CharSequences.toCharArray(edgeCharSequence);
|
||||
this.outgoingEdgesAsList = new AtomicReferenceArrayListAdapter<Node>(this.outgoingEdges);
|
||||
}
|
||||
|
||||
@Override
|
||||
public CharSequence getIncomingEdge() {
|
||||
return CharSequences.fromCharArray(incomingEdgeCharArray);
|
||||
}
|
||||
|
||||
@Override
|
||||
public Character getIncomingEdgeFirstCharacter() {
|
||||
return incomingEdgeCharArray[0];
|
||||
}
|
||||
|
||||
@Override
|
||||
public Object getValue() {
|
||||
return null;
|
||||
}
|
||||
|
||||
@Override
|
||||
public Node getOutgoingEdge(Character edgeFirstCharacter) {
|
||||
// Binary search for the index of the node whose edge starts with the given character.
|
||||
// Note that this binary search is safe in the face of concurrent modification due to constraints
|
||||
// we enforce on use of the array, as documented in the binarySearchForEdge method...
|
||||
int index = NodeUtil.binarySearchForEdge(outgoingEdges, edgeFirstCharacter);
|
||||
if (index < 0) {
|
||||
// No such edge exists...
|
||||
return null;
|
||||
}
|
||||
// Atomically return the child node at this index...
|
||||
return outgoingEdges.get(index);
|
||||
}
|
||||
|
||||
@Override
|
||||
public void updateOutgoingEdge(Node childNode) {
|
||||
// Binary search for the index of the node whose edge starts with the given character.
|
||||
// Note that this binary search is safe in the face of concurrent modification due to constraints
|
||||
// we enforce on use of the array, as documented in the binarySearchForEdge method...
|
||||
int index = NodeUtil.binarySearchForEdge(outgoingEdges, childNode.getIncomingEdgeFirstCharacter());
|
||||
if (index < 0) {
|
||||
throw new IllegalStateException("Cannot update the reference to the following child node for the edge starting with '" + childNode.getIncomingEdgeFirstCharacter() +"', no such edge already exists: " + childNode);
|
||||
}
|
||||
// Atomically update the child node at this index...
|
||||
outgoingEdges.set(index, childNode);
|
||||
}
|
||||
|
||||
@Override
|
||||
public List<Node> getOutgoingEdges() {
|
||||
return outgoingEdgesAsList;
|
||||
}
|
||||
|
||||
@Override
|
||||
public String toString() {
|
||||
StringBuilder sb = new StringBuilder();
|
||||
sb.append("Node{");
|
||||
sb.append("edge=").append(incomingEdgeCharArray);
|
||||
sb.append(", value=null");
|
||||
sb.append(", edges=").append(getOutgoingEdges());
|
||||
sb.append("}");
|
||||
return sb.toString();
|
||||
}
|
||||
}
|
||||
@ -0,0 +1,91 @@
|
||||
package org.xbib.datastructures.trie.concurrent.util;
|
||||
|
||||
import java.util.Arrays;
|
||||
import java.util.List;
|
||||
import java.util.concurrent.atomic.AtomicReferenceArray;
|
||||
|
||||
/**
|
||||
* Stores incoming edge as a {@code char[]} and outgoing edges as an {@link AtomicReferenceArray}. Does not store a
|
||||
* value and returns {@link VoidValue} for the value.
|
||||
*/
|
||||
public class CharArrayNodeNonLeafVoidValue implements Node {
|
||||
|
||||
// Characters in the edge arriving at this node from a parent node.
|
||||
// Once assigned, we never modify this...
|
||||
private final char[] incomingEdgeCharArray;
|
||||
|
||||
// References to child nodes representing outgoing edges from this node.
|
||||
// Once assigned we never add or remove references, but we do update existing references to point to new child
|
||||
// nodes provided new edges start with the same first character...
|
||||
private final AtomicReferenceArray<Node> outgoingEdges;
|
||||
|
||||
// A read-only List wrapper around the outgoingEdges AtomicReferenceArray...
|
||||
private final List<Node> outgoingEdgesAsList;
|
||||
|
||||
public CharArrayNodeNonLeafVoidValue(CharSequence edgeCharSequence, List<Node> outgoingEdges) {
|
||||
Node[] childNodeArray = outgoingEdges.toArray(new Node[outgoingEdges.size()]);
|
||||
// Sort the child nodes...
|
||||
Arrays.sort(childNodeArray, new NodeCharacterComparator());
|
||||
this.outgoingEdges = new AtomicReferenceArray<Node>(childNodeArray);
|
||||
this.incomingEdgeCharArray = CharSequences.toCharArray(edgeCharSequence);
|
||||
this.outgoingEdgesAsList = new AtomicReferenceArrayListAdapter<Node>(this.outgoingEdges);
|
||||
}
|
||||
|
||||
@Override
|
||||
public CharSequence getIncomingEdge() {
|
||||
return CharSequences.fromCharArray(incomingEdgeCharArray);
|
||||
}
|
||||
|
||||
@Override
|
||||
public Character getIncomingEdgeFirstCharacter() {
|
||||
return incomingEdgeCharArray[0];
|
||||
}
|
||||
|
||||
@Override
|
||||
public Object getValue() {
|
||||
return VoidValue.SINGLETON;
|
||||
}
|
||||
|
||||
@Override
|
||||
public Node getOutgoingEdge(Character edgeFirstCharacter) {
|
||||
// Binary search for the index of the node whose edge starts with the given character.
|
||||
// Note that this binary search is safe in the face of concurrent modification due to constraints
|
||||
// we enforce on use of the array, as documented in the binarySearchForEdge method...
|
||||
int index = NodeUtil.binarySearchForEdge(outgoingEdges, edgeFirstCharacter);
|
||||
if (index < 0) {
|
||||
// No such edge exists...
|
||||
return null;
|
||||
}
|
||||
// Atomically return the child node at this index...
|
||||
return outgoingEdges.get(index);
|
||||
}
|
||||
|
||||
@Override
|
||||
public void updateOutgoingEdge(Node childNode) {
|
||||
// Binary search for the index of the node whose edge starts with the given character.
|
||||
// Note that this binary search is safe in the face of concurrent modification due to constraints
|
||||
// we enforce on use of the array, as documented in the binarySearchForEdge method...
|
||||
int index = NodeUtil.binarySearchForEdge(outgoingEdges, childNode.getIncomingEdgeFirstCharacter());
|
||||
if (index < 0) {
|
||||
throw new IllegalStateException("Cannot update the reference to the following child node for the edge starting with '" + childNode.getIncomingEdgeFirstCharacter() +"', no such edge already exists: " + childNode);
|
||||
}
|
||||
// Atomically update the child node at this index...
|
||||
outgoingEdges.set(index, childNode);
|
||||
}
|
||||
|
||||
@Override
|
||||
public List<Node> getOutgoingEdges() {
|
||||
return outgoingEdgesAsList;
|
||||
}
|
||||
|
||||
@Override
|
||||
public String toString() {
|
||||
StringBuilder sb = new StringBuilder();
|
||||
sb.append("Node{");
|
||||
sb.append("edge=").append(incomingEdgeCharArray);
|
||||
sb.append(", value=").append(VoidValue.SINGLETON);
|
||||
sb.append(", edges=").append(getOutgoingEdges());
|
||||
sb.append("}");
|
||||
return sb.toString();
|
||||
}
|
||||
}
|
||||
@ -0,0 +1,115 @@
|
||||
package org.xbib.datastructures.trie.concurrent.util;
|
||||
|
||||
import java.util.Arrays;
|
||||
import java.util.List;
|
||||
import java.util.concurrent.atomic.AtomicReferenceArray;
|
||||
|
||||
/**
|
||||
* A implementation of the {@link Node} interface which stores the incoming edge as a {@link CharSequence} (a
|
||||
* <i>view</i> onto the original key) rather than copying the edge into a character array. Stores all variables and
|
||||
* supports all behaviours required by the tree, but still could be more memory efficient.
|
||||
* <p/>
|
||||
* See {@link NodeFactory} for documentation on how alternative
|
||||
* node implementations can be created to reduce memory overhead. See the {@link Node} interface for details on how
|
||||
* to write memory-efficient nodes.
|
||||
* <p/>
|
||||
* This implementation stores references to child nodes in an {@link AtomicReferenceArray}, in ascending sorted order
|
||||
* of the first character of the edges which child nodes define.
|
||||
* <p/>
|
||||
* The {@link #getOutgoingEdge(Character)} method uses binary search to locate a requested node, given the first character
|
||||
* of an edge indicated. The node is then read and returned atomically from the {@link AtomicReferenceArray}.
|
||||
* <p/>
|
||||
* The {@link #updateOutgoingEdge(Node)} method ensures that any
|
||||
* attempt to update a reference to a child node preserves the constraints defined in the {@link Node} interface. New
|
||||
* child nodes are written atomically to the {@link java.util.concurrent.atomic.AtomicReferenceArray}.
|
||||
* <p/>
|
||||
* The constraints defined in the {@link Node} interface ensure that the {@link AtomicReferenceArray} always remains in
|
||||
* ascending sorted order regardless of modifications performed concurrently, as long as the modifications comply with
|
||||
* the constraints. This node enforces those constraints.
|
||||
*/
|
||||
public class CharSequenceNodeDefault implements Node {
|
||||
|
||||
// Characters in the edge arriving at this node from a parent node.
|
||||
// Once assigned, we never modify this...
|
||||
private final CharSequence incomingEdgeCharSequence;
|
||||
|
||||
// References to child nodes representing outgoing edges from this node.
|
||||
// Once assigned we never add or remove references, but we do update existing references to point to new child
|
||||
// nodes provided new edges start with the same first character...
|
||||
private final AtomicReferenceArray<Node> outgoingEdges;
|
||||
|
||||
// A read-only List wrapper around the outgoingEdges AtomicReferenceArray...
|
||||
private final List<Node> outgoingEdgesAsList;
|
||||
|
||||
// An arbitrary value which the application associates with a key matching the path to this node in the tree.
|
||||
// This value can be null...
|
||||
private final Object value;
|
||||
|
||||
public CharSequenceNodeDefault(CharSequence edgeCharSequence, Object value, List<Node> outgoingEdges) {
|
||||
Node[] childNodeArray = outgoingEdges.toArray(new Node[outgoingEdges.size()]);
|
||||
// Sort the child nodes...
|
||||
Arrays.sort(childNodeArray, new NodeCharacterComparator());
|
||||
this.outgoingEdges = new AtomicReferenceArray<Node>(childNodeArray);
|
||||
this.incomingEdgeCharSequence = edgeCharSequence;
|
||||
this.value = value;
|
||||
this.outgoingEdgesAsList = new AtomicReferenceArrayListAdapter<Node>(this.outgoingEdges);
|
||||
}
|
||||
|
||||
@Override
|
||||
public CharSequence getIncomingEdge() {
|
||||
return incomingEdgeCharSequence;
|
||||
}
|
||||
|
||||
@Override
|
||||
public Character getIncomingEdgeFirstCharacter() {
|
||||
return incomingEdgeCharSequence.charAt(0);
|
||||
}
|
||||
|
||||
@Override
|
||||
public Object getValue() {
|
||||
return value;
|
||||
}
|
||||
|
||||
@Override
|
||||
public Node getOutgoingEdge(Character edgeFirstCharacter) {
|
||||
// Binary search for the index of the node whose edge starts with the given character.
|
||||
// Note that this binary search is safe in the face of concurrent modification due to constraints
|
||||
// we enforce on use of the array, as documented in the binarySearchForEdge method...
|
||||
int index = NodeUtil.binarySearchForEdge(outgoingEdges, edgeFirstCharacter);
|
||||
if (index < 0) {
|
||||
// No such edge exists...
|
||||
return null;
|
||||
}
|
||||
// Atomically return the child node at this index...
|
||||
return outgoingEdges.get(index);
|
||||
}
|
||||
|
||||
@Override
|
||||
public void updateOutgoingEdge(Node childNode) {
|
||||
// Binary search for the index of the node whose edge starts with the given character.
|
||||
// Note that this binary search is safe in the face of concurrent modification due to constraints
|
||||
// we enforce on use of the array, as documented in the binarySearchForEdge method...
|
||||
int index = NodeUtil.binarySearchForEdge(outgoingEdges, childNode.getIncomingEdgeFirstCharacter());
|
||||
if (index < 0) {
|
||||
throw new IllegalStateException("Cannot update the reference to the following child node for the edge starting with '" + childNode.getIncomingEdgeFirstCharacter() +"', no such edge already exists: " + childNode);
|
||||
}
|
||||
// Atomically update the child node at this index...
|
||||
outgoingEdges.set(index, childNode);
|
||||
}
|
||||
|
||||
@Override
|
||||
public List<Node> getOutgoingEdges() {
|
||||
return outgoingEdgesAsList;
|
||||
}
|
||||
|
||||
@Override
|
||||
public String toString() {
|
||||
StringBuilder sb = new StringBuilder();
|
||||
sb.append("Node{");
|
||||
sb.append("edge=").append(incomingEdgeCharSequence);
|
||||
sb.append(", value=").append(value);
|
||||
sb.append(", edges=").append(getOutgoingEdges());
|
||||
sb.append("}");
|
||||
return sb.toString();
|
||||
}
|
||||
}
|
||||
@ -0,0 +1,61 @@
|
||||
package org.xbib.datastructures.trie.concurrent.util;
|
||||
|
||||
import java.util.Collections;
|
||||
import java.util.List;
|
||||
|
||||
/**
|
||||
* Stores only incoming edge as a {@link CharSequence} (a <i>view</i> onto the original key) rather than copying the
|
||||
* edge into a character array. Returns {@code null} for the value. Does <b>not</b> store any outgoing edges.
|
||||
*/
|
||||
public class CharSequenceNodeLeafNullValue implements Node {
|
||||
|
||||
|
||||
// Characters in the edge arriving at this node from a parent node.
|
||||
// Once assigned, we never modify this...
|
||||
private final CharSequence incomingEdgeCharSequence;
|
||||
|
||||
public CharSequenceNodeLeafNullValue(CharSequence edgeCharSequence) {
|
||||
this.incomingEdgeCharSequence = edgeCharSequence;
|
||||
}
|
||||
|
||||
@Override
|
||||
public CharSequence getIncomingEdge() {
|
||||
return incomingEdgeCharSequence;
|
||||
}
|
||||
|
||||
@Override
|
||||
public Character getIncomingEdgeFirstCharacter() {
|
||||
return incomingEdgeCharSequence.charAt(0);
|
||||
}
|
||||
|
||||
@Override
|
||||
public Object getValue() {
|
||||
return null;
|
||||
}
|
||||
|
||||
@Override
|
||||
public Node getOutgoingEdge(Character edgeFirstCharacter) {
|
||||
return null;
|
||||
}
|
||||
|
||||
@Override
|
||||
public void updateOutgoingEdge(Node childNode) {
|
||||
throw new IllegalStateException("Cannot update the reference to the following child node for the edge starting with '" + childNode.getIncomingEdgeFirstCharacter() +"', no such edge already exists: " + childNode);
|
||||
}
|
||||
|
||||
@Override
|
||||
public List<Node> getOutgoingEdges() {
|
||||
return Collections.emptyList();
|
||||
}
|
||||
|
||||
@Override
|
||||
public String toString() {
|
||||
StringBuilder sb = new StringBuilder();
|
||||
sb.append("Node{");
|
||||
sb.append("edge=").append(incomingEdgeCharSequence);
|
||||
sb.append(", value=null");
|
||||
sb.append(", edges=[]");
|
||||
sb.append("}");
|
||||
return sb.toString();
|
||||
}
|
||||
}
|
||||
@ -0,0 +1,61 @@
|
||||
package org.xbib.datastructures.trie.concurrent.util;
|
||||
|
||||
import java.util.Collections;
|
||||
import java.util.List;
|
||||
|
||||
/**
|
||||
* Stores only incoming edge as a {@link CharSequence} (a <i>view</i> onto the original key) rather than copying the
|
||||
* edge into a character array. Returns {@link VoidValue} for the value. Does <b>not</b> store any outgoing edges.
|
||||
*/
|
||||
public class CharSequenceNodeLeafVoidValue implements Node {
|
||||
|
||||
|
||||
// Characters in the edge arriving at this node from a parent node.
|
||||
// Once assigned, we never modify this...
|
||||
private final CharSequence incomingEdgeCharSequence;
|
||||
|
||||
public CharSequenceNodeLeafVoidValue(CharSequence edgeCharSequence) {
|
||||
this.incomingEdgeCharSequence = edgeCharSequence;
|
||||
}
|
||||
|
||||
@Override
|
||||
public CharSequence getIncomingEdge() {
|
||||
return incomingEdgeCharSequence;
|
||||
}
|
||||
|
||||
@Override
|
||||
public Character getIncomingEdgeFirstCharacter() {
|
||||
return incomingEdgeCharSequence.charAt(0);
|
||||
}
|
||||
|
||||
@Override
|
||||
public Object getValue() {
|
||||
return VoidValue.SINGLETON;
|
||||
}
|
||||
|
||||
@Override
|
||||
public Node getOutgoingEdge(Character edgeFirstCharacter) {
|
||||
return null;
|
||||
}
|
||||
|
||||
@Override
|
||||
public void updateOutgoingEdge(Node childNode) {
|
||||
throw new IllegalStateException("Cannot update the reference to the following child node for the edge starting with '" + childNode.getIncomingEdgeFirstCharacter() +"', no such edge already exists: " + childNode);
|
||||
}
|
||||
|
||||
@Override
|
||||
public List<Node> getOutgoingEdges() {
|
||||
return Collections.emptyList();
|
||||
}
|
||||
|
||||
@Override
|
||||
public String toString() {
|
||||
StringBuilder sb = new StringBuilder();
|
||||
sb.append("Node{");
|
||||
sb.append("edge=").append(incomingEdgeCharSequence);
|
||||
sb.append(", value=").append(VoidValue.SINGLETON);
|
||||
sb.append(", edges=[]");
|
||||
sb.append("}");
|
||||
return sb.toString();
|
||||
}
|
||||
}
|
||||
@ -0,0 +1,67 @@
|
||||
package org.xbib.datastructures.trie.concurrent.util;
|
||||
|
||||
import java.util.Collections;
|
||||
import java.util.List;
|
||||
|
||||
/**
|
||||
* Stores incoming edge as a {@link CharSequence} (a <i>view</i> onto the original key) rather than copying the
|
||||
* edge into a character array. Also stores a reference to a value. Does <b>not</b> store any outgoing edges.
|
||||
*/
|
||||
public class CharSequenceNodeLeafWithValue implements Node {
|
||||
|
||||
|
||||
// Characters in the edge arriving at this node from a parent node.
|
||||
// Once assigned, we never modify this...
|
||||
private final CharSequence incomingEdgeCharSequence;
|
||||
|
||||
// An arbitrary value which the application associates with a key matching the path to this node in the tree.
|
||||
// This value can be null...
|
||||
private final Object value;
|
||||
|
||||
public CharSequenceNodeLeafWithValue(CharSequence edgeCharSequence, Object value) {
|
||||
// Sort the child nodes...
|
||||
this.incomingEdgeCharSequence = edgeCharSequence;
|
||||
this.value = value;
|
||||
}
|
||||
|
||||
@Override
|
||||
public CharSequence getIncomingEdge() {
|
||||
return incomingEdgeCharSequence;
|
||||
}
|
||||
|
||||
@Override
|
||||
public Character getIncomingEdgeFirstCharacter() {
|
||||
return incomingEdgeCharSequence.charAt(0);
|
||||
}
|
||||
|
||||
@Override
|
||||
public Object getValue() {
|
||||
return value;
|
||||
}
|
||||
|
||||
@Override
|
||||
public Node getOutgoingEdge(Character edgeFirstCharacter) {
|
||||
return null;
|
||||
}
|
||||
|
||||
@Override
|
||||
public void updateOutgoingEdge(Node childNode) {
|
||||
throw new IllegalStateException("Cannot update the reference to the following child node for the edge starting with '" + childNode.getIncomingEdgeFirstCharacter() +"', no such edge already exists: " + childNode);
|
||||
}
|
||||
|
||||
@Override
|
||||
public List<Node> getOutgoingEdges() {
|
||||
return Collections.emptyList();
|
||||
}
|
||||
|
||||
@Override
|
||||
public String toString() {
|
||||
StringBuilder sb = new StringBuilder();
|
||||
sb.append("Node{");
|
||||
sb.append("edge=").append(incomingEdgeCharSequence);
|
||||
sb.append(", value=").append(value);
|
||||
sb.append(", edges=[]");
|
||||
sb.append("}");
|
||||
return sb.toString();
|
||||
}
|
||||
}
|
||||
@ -0,0 +1,93 @@
|
||||
package org.xbib.datastructures.trie.concurrent.util;
|
||||
|
||||
import java.util.Arrays;
|
||||
import java.util.List;
|
||||
import java.util.concurrent.atomic.AtomicReferenceArray;
|
||||
|
||||
/**
|
||||
* Stores incoming edge as a {@link CharSequence} (a <i>view</i> onto the original key) rather than copying the edge
|
||||
* into a character array, and stores outgoing edges as an {@link AtomicReferenceArray}. Does not store a
|
||||
* value and returns {@code null} for the value.
|
||||
*/
|
||||
public class CharSequenceNodeNonLeafNullValue implements Node {
|
||||
|
||||
|
||||
// Characters in the edge arriving at this node from a parent node.
|
||||
// Once assigned, we never modify this...
|
||||
private final CharSequence incomingEdgeCharSequence;
|
||||
|
||||
// References to child nodes representing outgoing edges from this node.
|
||||
// Once assigned we never add or remove references, but we do update existing references to point to new child
|
||||
// nodes provided new edges start with the same first character...
|
||||
private final AtomicReferenceArray<Node> outgoingEdges;
|
||||
|
||||
// A read-only List wrapper around the outgoingEdges AtomicReferenceArray...
|
||||
private final List<Node> outgoingEdgesAsList;
|
||||
|
||||
public CharSequenceNodeNonLeafNullValue(CharSequence edgeCharSequence, List<Node> outgoingEdges) {
|
||||
Node[] childNodeArray = outgoingEdges.toArray(new Node[outgoingEdges.size()]);
|
||||
// Sort the child nodes...
|
||||
Arrays.sort(childNodeArray, new NodeCharacterComparator());
|
||||
this.outgoingEdges = new AtomicReferenceArray<Node>(childNodeArray);
|
||||
this.incomingEdgeCharSequence = edgeCharSequence;
|
||||
this.outgoingEdgesAsList = new AtomicReferenceArrayListAdapter<Node>(this.outgoingEdges);
|
||||
}
|
||||
|
||||
@Override
|
||||
public CharSequence getIncomingEdge() {
|
||||
return incomingEdgeCharSequence;
|
||||
}
|
||||
|
||||
@Override
|
||||
public Character getIncomingEdgeFirstCharacter() {
|
||||
return incomingEdgeCharSequence.charAt(0);
|
||||
}
|
||||
|
||||
@Override
|
||||
public Object getValue() {
|
||||
return null;
|
||||
}
|
||||
|
||||
@Override
|
||||
public Node getOutgoingEdge(Character edgeFirstCharacter) {
|
||||
// Binary search for the index of the node whose edge starts with the given character.
|
||||
// Note that this binary search is safe in the face of concurrent modification due to constraints
|
||||
// we enforce on use of the array, as documented in the binarySearchForEdge method...
|
||||
int index = NodeUtil.binarySearchForEdge(outgoingEdges, edgeFirstCharacter);
|
||||
if (index < 0) {
|
||||
// No such edge exists...
|
||||
return null;
|
||||
}
|
||||
// Atomically return the child node at this index...
|
||||
return outgoingEdges.get(index);
|
||||
}
|
||||
|
||||
@Override
|
||||
public void updateOutgoingEdge(Node childNode) {
|
||||
// Binary search for the index of the node whose edge starts with the given character.
|
||||
// Note that this binary search is safe in the face of concurrent modification due to constraints
|
||||
// we enforce on use of the array, as documented in the binarySearchForEdge method...
|
||||
int index = NodeUtil.binarySearchForEdge(outgoingEdges, childNode.getIncomingEdgeFirstCharacter());
|
||||
if (index < 0) {
|
||||
throw new IllegalStateException("Cannot update the reference to the following child node for the edge starting with '" + childNode.getIncomingEdgeFirstCharacter() +"', no such edge already exists: " + childNode);
|
||||
}
|
||||
// Atomically update the child node at this index...
|
||||
outgoingEdges.set(index, childNode);
|
||||
}
|
||||
|
||||
@Override
|
||||
public List<Node> getOutgoingEdges() {
|
||||
return outgoingEdgesAsList;
|
||||
}
|
||||
|
||||
@Override
|
||||
public String toString() {
|
||||
StringBuilder sb = new StringBuilder();
|
||||
sb.append("Node{");
|
||||
sb.append("edge=").append(incomingEdgeCharSequence);
|
||||
sb.append(", value=null");
|
||||
sb.append(", edges=").append(getOutgoingEdges());
|
||||
sb.append("}");
|
||||
return sb.toString();
|
||||
}
|
||||
}
|
||||
@ -0,0 +1,93 @@
|
||||
package org.xbib.datastructures.trie.concurrent.util;
|
||||
|
||||
import java.util.Arrays;
|
||||
import java.util.List;
|
||||
import java.util.concurrent.atomic.AtomicReferenceArray;
|
||||
|
||||
/**
|
||||
* Stores incoming edge as a {@link CharSequence} (a <i>view</i> onto the original key) rather than copying the edge
|
||||
* into a character array, and stores outgoing edges as an {@link AtomicReferenceArray}. Does not store a
|
||||
* value and returns {@link VoidValue} for the value.
|
||||
*/
|
||||
public class CharSequenceNodeNonLeafVoidValue implements Node {
|
||||
|
||||
|
||||
// Characters in the edge arriving at this node from a parent node.
|
||||
// Once assigned, we never modify this...
|
||||
private final CharSequence incomingEdgeCharSequence;
|
||||
|
||||
// References to child nodes representing outgoing edges from this node.
|
||||
// Once assigned we never add or remove references, but we do update existing references to point to new child
|
||||
// nodes provided new edges start with the same first character...
|
||||
private final AtomicReferenceArray<Node> outgoingEdges;
|
||||
|
||||
// A read-only List wrapper around the outgoingEdges AtomicReferenceArray...
|
||||
private final List<Node> outgoingEdgesAsList;
|
||||
|
||||
public CharSequenceNodeNonLeafVoidValue(CharSequence edgeCharSequence, List<Node> outgoingEdges) {
|
||||
Node[] childNodeArray = outgoingEdges.toArray(new Node[outgoingEdges.size()]);
|
||||
// Sort the child nodes...
|
||||
Arrays.sort(childNodeArray, new NodeCharacterComparator());
|
||||
this.outgoingEdges = new AtomicReferenceArray<Node>(childNodeArray);
|
||||
this.incomingEdgeCharSequence = edgeCharSequence;
|
||||
this.outgoingEdgesAsList = new AtomicReferenceArrayListAdapter<Node>(this.outgoingEdges);
|
||||
}
|
||||
|
||||
@Override
|
||||
public CharSequence getIncomingEdge() {
|
||||
return incomingEdgeCharSequence;
|
||||
}
|
||||
|
||||
@Override
|
||||
public Character getIncomingEdgeFirstCharacter() {
|
||||
return incomingEdgeCharSequence.charAt(0);
|
||||
}
|
||||
|
||||
@Override
|
||||
public Object getValue() {
|
||||
return VoidValue.SINGLETON;
|
||||
}
|
||||
|
||||
@Override
|
||||
public Node getOutgoingEdge(Character edgeFirstCharacter) {
|
||||
// Binary search for the index of the node whose edge starts with the given character.
|
||||
// Note that this binary search is safe in the face of concurrent modification due to constraints
|
||||
// we enforce on use of the array, as documented in the binarySearchForEdge method...
|
||||
int index = NodeUtil.binarySearchForEdge(outgoingEdges, edgeFirstCharacter);
|
||||
if (index < 0) {
|
||||
// No such edge exists...
|
||||
return null;
|
||||
}
|
||||
// Atomically return the child node at this index...
|
||||
return outgoingEdges.get(index);
|
||||
}
|
||||
|
||||
@Override
|
||||
public void updateOutgoingEdge(Node childNode) {
|
||||
// Binary search for the index of the node whose edge starts with the given character.
|
||||
// Note that this binary search is safe in the face of concurrent modification due to constraints
|
||||
// we enforce on use of the array, as documented in the binarySearchForEdge method...
|
||||
int index = NodeUtil.binarySearchForEdge(outgoingEdges, childNode.getIncomingEdgeFirstCharacter());
|
||||
if (index < 0) {
|
||||
throw new IllegalStateException("Cannot update the reference to the following child node for the edge starting with '" + childNode.getIncomingEdgeFirstCharacter() +"', no such edge already exists: " + childNode);
|
||||
}
|
||||
// Atomically update the child node at this index...
|
||||
outgoingEdges.set(index, childNode);
|
||||
}
|
||||
|
||||
@Override
|
||||
public List<Node> getOutgoingEdges() {
|
||||
return outgoingEdgesAsList;
|
||||
}
|
||||
|
||||
@Override
|
||||
public String toString() {
|
||||
StringBuilder sb = new StringBuilder();
|
||||
sb.append("Node{");
|
||||
sb.append("edge=").append(incomingEdgeCharSequence);
|
||||
sb.append(", value=").append(VoidValue.SINGLETON);
|
||||
sb.append(", edges=").append(getOutgoingEdges());
|
||||
sb.append("}");
|
||||
return sb.toString();
|
||||
}
|
||||
}
|
||||
@ -0,0 +1,130 @@
|
||||
package org.xbib.datastructures.trie.concurrent.util;
|
||||
|
||||
import java.util.Iterator;
|
||||
|
||||
public class CharSequences {
|
||||
|
||||
/**
|
||||
* Private constructor, not used.
|
||||
*/
|
||||
CharSequences() {
|
||||
}
|
||||
|
||||
public static Iterable<CharSequence> generateSuffixes(final CharSequence input) {
|
||||
return () -> new Iterator<CharSequence>() {
|
||||
int currentIndex = 0;
|
||||
@Override
|
||||
public boolean hasNext() {
|
||||
return currentIndex < input.length();
|
||||
}
|
||||
|
||||
@Override
|
||||
public CharSequence next() {
|
||||
return input.subSequence(currentIndex++, input.length());
|
||||
}
|
||||
|
||||
@Override
|
||||
public void remove() {
|
||||
throw new UnsupportedOperationException("Modification not supported");
|
||||
}
|
||||
};
|
||||
}
|
||||
|
||||
public static Iterable<CharSequence> generatePrefixes(final CharSequence input) {
|
||||
return () -> new Iterator<CharSequence>() {
|
||||
int currentIndex = 0;
|
||||
|
||||
@Override
|
||||
public boolean hasNext() {
|
||||
return currentIndex < input.length();
|
||||
}
|
||||
|
||||
@Override
|
||||
public CharSequence next() {
|
||||
return input.subSequence(0, ++currentIndex);
|
||||
}
|
||||
|
||||
@Override
|
||||
public void remove() {
|
||||
throw new UnsupportedOperationException("Modification not supported");
|
||||
}
|
||||
};
|
||||
}
|
||||
|
||||
public static CharSequence getCommonPrefix(CharSequence first, CharSequence second) {
|
||||
int minLength = Math.min(first.length(), second.length());
|
||||
for (int i = 0; i < minLength; i++) {
|
||||
if (first.charAt(i) != second.charAt(i)) {
|
||||
return first.subSequence(0, i);
|
||||
}
|
||||
}
|
||||
return first.subSequence(0, minLength);
|
||||
}
|
||||
|
||||
public static CharSequence getSuffix(CharSequence input, int startIndex) {
|
||||
if (startIndex >= input.length()) {
|
||||
return "";
|
||||
}
|
||||
return input.subSequence(startIndex, input.length());
|
||||
}
|
||||
|
||||
public static CharSequence getPrefix(CharSequence input, int endIndex) {
|
||||
if (endIndex > input.length()) {
|
||||
return input;
|
||||
}
|
||||
return input.subSequence(0, endIndex);
|
||||
}
|
||||
|
||||
public static CharSequence subtractPrefix(CharSequence main, CharSequence prefix) {
|
||||
int startIndex = prefix.length();
|
||||
int mainLength = main.length();
|
||||
if (startIndex > mainLength) {
|
||||
return "";
|
||||
}
|
||||
return main.subSequence(startIndex, mainLength);
|
||||
}
|
||||
|
||||
public static CharSequence concatenate(final CharSequence first, final CharSequence second) {
|
||||
return new StringBuilder().append(first).append(second);
|
||||
}
|
||||
|
||||
public static CharSequence reverse(CharSequence input) {
|
||||
return new StringBuilder(input.length()).append(input).reverse();
|
||||
}
|
||||
|
||||
/**
|
||||
* Returns a {@link CharSequence} which wraps the given {@code char[]}. Note that this {@link CharSequence} will
|
||||
* reflect any changes to the {@code char[]}.
|
||||
*
|
||||
* @param characters The {@code char[]} to wrap
|
||||
* @return A {@link CharSequence} which wraps the given {@code char[]}
|
||||
*/
|
||||
public static CharSequence fromCharArray(final char[] characters) {
|
||||
return new StringBuilder(characters.length).append(characters);
|
||||
}
|
||||
|
||||
/**
|
||||
* Copies the given {@link CharSequence} into a new {@code char[]}.
|
||||
*
|
||||
* @param charSequence The {@link CharSequence} to copy
|
||||
* @return A new {@code char[]} populated with characters from the given {@link CharSequence}
|
||||
*/
|
||||
public static char[] toCharArray(CharSequence charSequence) {
|
||||
final int numChars = charSequence.length();
|
||||
char[] charArray = new char[numChars];
|
||||
for (int i = 0; i < numChars; i++) {
|
||||
charArray[i] = charSequence.charAt(i);
|
||||
}
|
||||
return charArray;
|
||||
}
|
||||
|
||||
public static String toString(CharSequence charSequence) {
|
||||
if (charSequence == null) {
|
||||
return null;
|
||||
}
|
||||
if (charSequence instanceof String) {
|
||||
return (String)charSequence;
|
||||
}
|
||||
return String.valueOf(charSequence);
|
||||
}
|
||||
}
|
||||
@ -0,0 +1,63 @@
|
||||
package org.xbib.datastructures.trie.concurrent.util;
|
||||
|
||||
import java.util.List;
|
||||
|
||||
/**
|
||||
* A {@link NodeFactory} which creates various implementations of {@link Node} objects all of which store incoming
|
||||
* edge characters as a character array inside the node.
|
||||
* <p/>
|
||||
* Returns an optimal node implementation depending on arguments supplied, which will be one of:
|
||||
* <ul>
|
||||
* <li>{@link CharArrayNodeDefault} - contains all possible fields</li>
|
||||
* <li>{@link CharArrayNodeNonLeafNullValue} - does not store a value, returns {@code null} for value</li>
|
||||
* <li>{@link CharArrayNodeNonLeafVoidValue} - does not store a value, returns {@link VoidValue} for value</li>
|
||||
* <li>{@link CharArrayNodeLeafVoidValue} - does not store child edges or a value, returns {@link VoidValue} for value</li>
|
||||
* <li>{@link CharArrayNodeLeafWithValue} - does not store child edges, but does store a value</li>
|
||||
* </ul>
|
||||
* <p/>
|
||||
* When the application supplies {@link VoidValue} for a value, this factory will omit actually storing that value
|
||||
* in the tree and will return one of the VoidValue-optimized nodes above which can reduce memory usage.
|
||||
*
|
||||
* @author Niall Gallagher
|
||||
*/
|
||||
public class DefaultCharArrayNodeFactory implements NodeFactory {
|
||||
|
||||
@Override
|
||||
public Node createNode(CharSequence edgeCharacters, Object value, List<Node> childNodes, boolean isRoot) {
|
||||
if (edgeCharacters == null) {
|
||||
throw new IllegalStateException("The edgeCharacters argument was null");
|
||||
}
|
||||
if (!isRoot && edgeCharacters.length() == 0) {
|
||||
throw new IllegalStateException("Invalid edge characters for non-root node: " + CharSequences.toString(edgeCharacters));
|
||||
}
|
||||
if (childNodes == null) {
|
||||
throw new IllegalStateException("The childNodes argument was null");
|
||||
}
|
||||
NodeUtil.ensureNoDuplicateEdges(childNodes);
|
||||
if (childNodes.isEmpty()) {
|
||||
// Leaf node...
|
||||
if (value instanceof VoidValue) {
|
||||
return new CharArrayNodeLeafVoidValue(edgeCharacters);
|
||||
}
|
||||
else if (value != null) {
|
||||
return new CharArrayNodeLeafWithValue(edgeCharacters, value);
|
||||
}
|
||||
else {
|
||||
return new CharArrayNodeLeafNullValue(edgeCharacters);
|
||||
}
|
||||
}
|
||||
else {
|
||||
// Non-leaf node...
|
||||
if (value instanceof VoidValue) {
|
||||
return new CharArrayNodeNonLeafVoidValue(edgeCharacters, childNodes);
|
||||
}
|
||||
else if (value == null) {
|
||||
return new CharArrayNodeNonLeafNullValue(edgeCharacters, childNodes);
|
||||
}
|
||||
else {
|
||||
return new CharArrayNodeDefault(edgeCharacters, value, childNodes);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
}
|
||||
@ -0,0 +1,66 @@
|
||||
package org.xbib.datastructures.trie.concurrent.util;
|
||||
|
||||
import java.util.List;
|
||||
|
||||
/**
|
||||
* A {@link NodeFactory} which creates various implementations of {@link Node} objects all of which store incoming
|
||||
* edge characters as a {@link CharSequence} (a <i>view</i> onto the original key) rather than copying the edge into a
|
||||
* character array.
|
||||
* <p/>
|
||||
* Returns an optimal node implementation depending on arguments supplied, which will be one of:
|
||||
* <ul>
|
||||
* <li>{@link CharSequenceNodeDefault} - contains all possible fields</li>
|
||||
* <li>{@link CharSequenceNodeNonLeafNullValue} - does not store a value, returns {@code null} for value</li>
|
||||
* <li>{@link CharSequenceNodeNonLeafVoidValue} - does not store a value, returns {@link VoidValue} for value</li>
|
||||
* <li>{@link CharSequenceNodeLeafVoidValue} - does not store child edges or a value, returns {@link VoidValue} for value</li>
|
||||
* <li>{@link CharSequenceNodeLeafWithValue} - does not store child edges, but does store a value</li>
|
||||
* </ul>
|
||||
* <p/>
|
||||
* When the application supplies {@link VoidValue} for a value, this factory will omit actually storing that value
|
||||
* in the tree and will return one of the Void-optimized nodes above which can reduce memory usage.
|
||||
*
|
||||
* @author Niall Gallagher
|
||||
*/
|
||||
public class DefaultCharSequenceNodeFactory implements NodeFactory {
|
||||
|
||||
@Override
|
||||
public Node createNode(CharSequence edgeCharacters, Object value, List<Node> childNodes, boolean isRoot) {
|
||||
if (edgeCharacters == null) {
|
||||
throw new IllegalStateException("The edgeCharacters argument was null");
|
||||
}
|
||||
if (!isRoot && edgeCharacters.length() == 0) {
|
||||
throw new IllegalStateException("Invalid edge characters for non-root node: " + CharSequences.toString(edgeCharacters));
|
||||
}
|
||||
if (childNodes == null) {
|
||||
throw new IllegalStateException("The childNodes argument was null");
|
||||
}
|
||||
NodeUtil.ensureNoDuplicateEdges(childNodes);
|
||||
|
||||
|
||||
if (childNodes.isEmpty()) {
|
||||
// Leaf node...
|
||||
if (value instanceof VoidValue) {
|
||||
return new CharSequenceNodeLeafVoidValue(edgeCharacters);
|
||||
}
|
||||
else if (value != null) {
|
||||
return new CharSequenceNodeLeafWithValue(edgeCharacters, value);
|
||||
}
|
||||
else {
|
||||
return new CharSequenceNodeLeafNullValue(edgeCharacters);
|
||||
}
|
||||
}
|
||||
else {
|
||||
// Non-leaf node...
|
||||
if (value instanceof VoidValue) {
|
||||
return new CharSequenceNodeNonLeafVoidValue(edgeCharacters, childNodes);
|
||||
}
|
||||
else if (value == null) {
|
||||
return new CharSequenceNodeNonLeafNullValue(edgeCharacters, childNodes);
|
||||
}
|
||||
else {
|
||||
return new CharSequenceNodeDefault(edgeCharacters, value, childNodes);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
}
|
||||
@ -0,0 +1,122 @@
|
||||
package org.xbib.datastructures.trie.concurrent.util;
|
||||
|
||||
import java.util.ArrayList;
|
||||
import java.util.Collection;
|
||||
import java.util.Iterator;
|
||||
import java.util.LinkedHashSet;
|
||||
import java.util.LinkedList;
|
||||
import java.util.List;
|
||||
import java.util.Set;
|
||||
|
||||
/**
|
||||
* Provides methods to convert {@link Iterable}s to {@link List}s and {@link Set}s.
|
||||
* <p/>
|
||||
* This class is mostly provided for backwards compatibility in applications which were programmed against
|
||||
* concurrent-trees 1.0.0, in which the tree APIs returned lists and sets instead of lazily-evaluated iterables.
|
||||
* <p/>
|
||||
* Note that in applications which would have simply iterated through the lists and sets returned by the old APIs,
|
||||
* the new approach of returning lazy iterables is more efficient. Applications can iterate the iterables returned
|
||||
* in exactly the same manner, and results will be the same.
|
||||
* <p/>
|
||||
* These methods are provided for convenience in applications which <i>actually</i> relied on List and Set-specific
|
||||
* features in the objects which were returned.
|
||||
* <p/>
|
||||
* Most methods in this class are somewhat similar to utilities in Google Guava; but are provided here to avoid a
|
||||
* dependency on Guava. Applications could use either these methods or Guava.
|
||||
*/
|
||||
public class Iterables {
|
||||
|
||||
// Most methods in this class are somewhat similar to utilities in Google Guava; but are provided here
|
||||
// to avoid a dependency on Guava. Applications could use either these methods or Guava.
|
||||
|
||||
/**
|
||||
* Copies elements from the given {@link Iterable} into a new {@link List}.
|
||||
* <p/>
|
||||
* The iteration order of the list returned, will be the same as that of the iterable.
|
||||
* <p/>
|
||||
* Be aware of the memory implications of copying objects from a lazy iterable into a collection;
|
||||
* usually it's better to just work with the iterable directly (i.e. by iterating it).
|
||||
*
|
||||
* @param iterable Provides elements to be copied into a new list
|
||||
* @param <T> The type of elements returned by the iterable
|
||||
* @return A new {@link List} which contains the elements which were returned by the iterable
|
||||
*/
|
||||
public static <T> List<T> toList(Iterable<T> iterable) {
|
||||
if (iterable instanceof Collection) {
|
||||
return new ArrayList<T>((Collection<T>)iterable);
|
||||
}
|
||||
else {
|
||||
List<T> list = new LinkedList<T>();
|
||||
for (T element : iterable) {
|
||||
list.add(element);
|
||||
}
|
||||
return list;
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Copies elements from the given {@link Iterable} into a new {@link Set}.
|
||||
* <p/>
|
||||
* The iteration order of the set returned, will be the same as that of the iterable.
|
||||
* <p/>
|
||||
* Be aware of the memory implications of copying objects from a lazy iterable into a collection;
|
||||
* usually it's better to just work with the iterable directly (i.e. by iterating it).
|
||||
*
|
||||
* @param iterable Provides elements to be copied into a new set
|
||||
* @param <T> The type of elements returned by the iterable
|
||||
* @return A new {@link Set} which contains the elements which were returned by the iterable
|
||||
*/
|
||||
public static <T> Set<T> toSet(Iterable<T> iterable) {
|
||||
if (iterable instanceof Collection) {
|
||||
// Return a LinkedHashSet instead of HashSet, to preserve iteration order...
|
||||
return new LinkedHashSet<T>((Collection<T>)iterable);
|
||||
}
|
||||
else {
|
||||
Set<T> list = new LinkedHashSet<T>();
|
||||
for (T element : iterable) {
|
||||
list.add(element);
|
||||
}
|
||||
return list;
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Returns a string representation of elements returned by the given {@link Iterable}.
|
||||
*
|
||||
* @param iterable Provides elements whose <code>toString</code> representations should be included in the string
|
||||
* @return A string representation of elements returned by the given {@link Iterable}
|
||||
*/
|
||||
public static String toString(Iterable<?> iterable) {
|
||||
StringBuilder sb = new StringBuilder();
|
||||
sb.append("[");
|
||||
for (Iterator<?> i = iterable.iterator(); i.hasNext();) {
|
||||
sb.append(i.next());
|
||||
if (i.hasNext()) {
|
||||
sb.append(", ");
|
||||
}
|
||||
}
|
||||
sb.append("]");
|
||||
return sb.toString();
|
||||
}
|
||||
|
||||
/**
|
||||
* Counts the number of elements returned by the given {@link Iterable}.
|
||||
*
|
||||
* @param iterable Provides elements to be counted
|
||||
* @return The number of elements returned by the iterable
|
||||
*/
|
||||
public static int count(Iterable<?> iterable) {
|
||||
int count = 0;
|
||||
//noinspection UnusedDeclaration
|
||||
for (Object next : iterable) {
|
||||
count++;
|
||||
}
|
||||
return count;
|
||||
}
|
||||
|
||||
/**
|
||||
* Private constructor, not used.
|
||||
*/
|
||||
Iterables() {
|
||||
}
|
||||
}
|
||||
@ -0,0 +1,45 @@
|
||||
package org.xbib.datastructures.trie.concurrent.util;
|
||||
|
||||
/**
|
||||
* Encapsulates a key and a value.
|
||||
*
|
||||
* @param <O> The type of the value
|
||||
*/
|
||||
public interface KeyValuePair<O> {
|
||||
|
||||
/**
|
||||
* Returns the key with which the value is associated
|
||||
* @return The key with which the value is associated
|
||||
*/
|
||||
CharSequence getKey();
|
||||
|
||||
/**
|
||||
* Returns the value associated with the key
|
||||
* @return The value associated with the key
|
||||
*/
|
||||
O getValue();
|
||||
|
||||
/**
|
||||
* Compares this {@link KeyValuePair} object with another for equality.
|
||||
* <p/>
|
||||
* This is implemented based on equality of the keys.
|
||||
*
|
||||
* @param o The other object to compare
|
||||
* @return True if the other object is also a {@link KeyValuePair} and is equal to this one as specified above
|
||||
*/
|
||||
@Override
|
||||
boolean equals(Object o);
|
||||
|
||||
/**
|
||||
* Returns a hash code for this object.
|
||||
*/
|
||||
@Override
|
||||
int hashCode();
|
||||
|
||||
/**
|
||||
* Returns a string representation as {@code (key, value)}.
|
||||
* @return A string representation as {@code (key, value)}
|
||||
*/
|
||||
@Override
|
||||
String toString();
|
||||
}
|
||||
@ -0,0 +1,76 @@
|
||||
package org.xbib.datastructures.trie.concurrent.util;
|
||||
|
||||
import java.util.Iterator;
|
||||
import java.util.NoSuchElementException;
|
||||
|
||||
/**
|
||||
* An unmodifiable iterator which computes the next element to return only when it is requested.
|
||||
* <p/>
|
||||
* This class is inspired by com.google.common.collect.AbstractIterator in Google Guava,
|
||||
* which was written by the Google Guava Authors, in particular by Kevin Bourrillion.
|
||||
*
|
||||
* @author Niall Gallagher
|
||||
*/
|
||||
public abstract class LazyIterator<T> implements Iterator<T> {
|
||||
|
||||
T next = null;
|
||||
|
||||
enum State { READY, NOT_READY, DONE, FAILED }
|
||||
|
||||
State state = State.NOT_READY;
|
||||
|
||||
@Override
|
||||
public void remove() {
|
||||
throw new UnsupportedOperationException("Iterator.remove() is not supported");
|
||||
}
|
||||
|
||||
@Override
|
||||
public final boolean hasNext() {
|
||||
if (state == State.FAILED) {
|
||||
throw new IllegalStateException("This iterator is in an inconsistent state, and can no longer be used, " +
|
||||
"due to an exception previously thrown by the computeNext() method");
|
||||
}
|
||||
switch (state) {
|
||||
case DONE:
|
||||
return false;
|
||||
case READY:
|
||||
return true;
|
||||
}
|
||||
return tryToComputeNext();
|
||||
}
|
||||
|
||||
boolean tryToComputeNext() {
|
||||
state = State.FAILED; // temporary pessimism
|
||||
next = computeNext();
|
||||
if (state != State.DONE) {
|
||||
state = State.READY;
|
||||
return true;
|
||||
}
|
||||
return false;
|
||||
}
|
||||
|
||||
@Override
|
||||
public final T next() {
|
||||
if (!hasNext()) {
|
||||
throw new NoSuchElementException();
|
||||
}
|
||||
state = State.NOT_READY;
|
||||
return next;
|
||||
}
|
||||
|
||||
/**
|
||||
*
|
||||
* @return a dummy value which if returned by the <code>computeNext()</code> method, signals that there are no more
|
||||
* elements to return
|
||||
*/
|
||||
protected final T endOfData() {
|
||||
state = State.DONE;
|
||||
return null;
|
||||
}
|
||||
|
||||
/**
|
||||
* @return The next element which the iterator should return, or the result of calling <code>endOfData()</code>
|
||||
* if there are no more elements to return
|
||||
*/
|
||||
protected abstract T computeNext();
|
||||
}
|
||||
@ -0,0 +1,136 @@
|
||||
package org.xbib.datastructures.trie.concurrent.util;
|
||||
|
||||
import java.util.List;
|
||||
|
||||
/**
|
||||
* Specifies the methods that nodes must implement.
|
||||
* <p/>
|
||||
* The main function of a node is to represent an "edge" in the tree. An edge is a connection from a parent node to a
|
||||
* child node which represents a sequence of characters. For practical reasons we store these characters in the child
|
||||
* node, to avoid needing separate Edge objects. All nodes except the root encode at least one character for an edge.
|
||||
* <p/>
|
||||
* Nodes contain several fields, but not all nodes will actually need to store values in every field. Therefore
|
||||
* some specialized implementations of this interface are possible, optimized for storing various combinations of
|
||||
* data items in reduced numbers of fields, to reduce memory overhead.
|
||||
* <p/>
|
||||
* Nodes are <u><i>partially immutable</i></u>:
|
||||
* <ul>
|
||||
* <li>
|
||||
* The <i>characters of an "edge"</i> encoded in within a node are <u>immutable</u> (these characters belong to
|
||||
* the edge arriving at the current node from a parent node)
|
||||
* </li>
|
||||
* <li>
|
||||
* The <i>number of outgoing edges</i> from a node (references to child nodes), and the <i>first characters of
|
||||
* those edges</i> are <u>immutable</u>
|
||||
* </li>
|
||||
* <li>
|
||||
* The <i>references to child nodes for existing edges</i> (as identified by their first characters) are
|
||||
* <u>mutable with constraints</u>; the reference to a child node for an existing edge may be updated to point
|
||||
* to a different child node as long as the new edge starts with the same first character
|
||||
* </li>
|
||||
* <li>
|
||||
* If a node stores a value, the reference to the value is <u>immutable</u> (values can be changed but it
|
||||
* requires recreating the node with the new value - this is to account for specialized node implementations
|
||||
* omitting a field for the value when not required)
|
||||
* </li>
|
||||
* </ul>
|
||||
* These constraints exist allow concurrent traversal and modifications to the tree. Nodes are required to implement
|
||||
* some operations <u>atomically</u>, see documentation on each method in this interface for details.
|
||||
* <p/>
|
||||
* Hints for specialized implementations of this Node interface:
|
||||
* <ul>
|
||||
* <li>
|
||||
* Leaf nodes do not need to store references to child nodes; a specialized node implementation
|
||||
* could eliminate a field and associated data structure for child node references
|
||||
* </li>
|
||||
* <li>
|
||||
* All leaf nodes store values
|
||||
* </li>
|
||||
* <li>
|
||||
* Some non-leaf nodes store values, some do not
|
||||
* </li>
|
||||
* <li>
|
||||
* Edge character data can be encoded using implementation-specific methods.
|
||||
* <p/>
|
||||
* Nodes are not required to store a {@link CharSequence} object verbatim, or use a particular implementation of
|
||||
* {@link CharSequence}, the only requirement is that they provide a {@link CharSequence} <i>view</i> onto
|
||||
* the character data.
|
||||
* <p/>
|
||||
* Character data can optionally be stored outside of the tree. {@link CharSequence}s can encode a start and
|
||||
* end offset (or length) as a view onto a larger string (possibly a view onto the original key inserted).
|
||||
* Furthermore end offset could be stored as length, relative to the start offset with variable length encoding
|
||||
* to avoid storing 4 bytes for the length. This option would have consequences for
|
||||
* garbage collection of large string keys however, therefore would mostly suit immutable data sets.
|
||||
* <p/>
|
||||
* Character data can be compressed. {@link CharSequence}s are free to store character data within the tree but
|
||||
* in a size-reduced encoding such as UTF-8
|
||||
* </li>
|
||||
* </ul>
|
||||
*
|
||||
* @author Niall Gallagher
|
||||
*/
|
||||
public interface Node extends NodeCharacterProvider {
|
||||
|
||||
/**
|
||||
* Returns the first character of the "edge" encoded in this node, belonging to the connection from a parent node to
|
||||
* this node.
|
||||
* <p/>
|
||||
*
|
||||
* @return The first character of the "edge" encoded in this node
|
||||
*/
|
||||
Character getIncomingEdgeFirstCharacter();
|
||||
|
||||
/**
|
||||
* Returns all characters of the "edge" encoded in this node, belonging to the connection from a parent node to this
|
||||
* node.
|
||||
*
|
||||
* @return All characters of the "edge" encoded in this node
|
||||
*/
|
||||
CharSequence getIncomingEdge();
|
||||
|
||||
/**
|
||||
* Returns a value object which has been associated with a key and which is stored in this node, or returns
|
||||
* <code>null</code> if no value is stored in this node.
|
||||
*
|
||||
* @return A value object which has been associated with a key and which is stored in this node, or returns
|
||||
* <code>null</code> if no value is stored in this node
|
||||
*/
|
||||
Object getValue();
|
||||
|
||||
|
||||
/**
|
||||
* Returns the child of this node whose edge starts with the given first character.
|
||||
* <p/>
|
||||
* This <i>read</i> must be performed <b><u>atomically</u></b>, in relation to writes made via
|
||||
* {@link #updateOutgoingEdge(Node)}.
|
||||
*
|
||||
* @param edgeFirstCharacter The first character of the edge for which the associated child node is required
|
||||
* @return The child of this node whose edge starts with the given first character, or <code>null</code> if this
|
||||
* node has no such outgoing edge
|
||||
*/
|
||||
Node getOutgoingEdge(Character edgeFirstCharacter);
|
||||
|
||||
/**
|
||||
* Updates the child node reference for a given edge (identified by its first character) to point to a different
|
||||
* child node.
|
||||
* <p/>
|
||||
* The first character of the given child node's edge must match the first character of an existing outgoing
|
||||
* edge from this node.
|
||||
* <p/>
|
||||
* This <i>write</i> must be performed <b><u>atomically</u></b>, in relation to reads made via
|
||||
* {@link #getOutgoingEdge(Character)}.
|
||||
*
|
||||
* @param childNode The new child node to associated with this edge
|
||||
*/
|
||||
void updateOutgoingEdge(Node childNode);
|
||||
|
||||
/**
|
||||
* Returns a read-only list of the child nodes to which this node has outgoing edges, i.e. child nodes which have
|
||||
* incoming edges from this node.
|
||||
* <p/>
|
||||
* It is intended that this method will be used for copying/cloning nodes.
|
||||
*
|
||||
* @return A read-only list of the child nodes to which this node has outgoing edges
|
||||
*/
|
||||
List<Node> getOutgoingEdges();
|
||||
}
|
||||
@ -0,0 +1,15 @@
|
||||
package org.xbib.datastructures.trie.concurrent.util;
|
||||
|
||||
import java.util.Comparator;
|
||||
|
||||
/**
|
||||
* Specifies binary search compatibility, and sorting compatibility, of nodes based on
|
||||
* {@link Node#getIncomingEdgeFirstCharacter()}.
|
||||
*/
|
||||
public class NodeCharacterComparator implements Comparator<NodeCharacterProvider> {
|
||||
|
||||
@Override
|
||||
public int compare(NodeCharacterProvider o1, NodeCharacterProvider o2) {
|
||||
return o1.getIncomingEdgeFirstCharacter().compareTo(o2.getIncomingEdgeFirstCharacter());
|
||||
}
|
||||
}
|
||||
@ -0,0 +1,20 @@
|
||||
package org.xbib.datastructures.trie.concurrent.util;
|
||||
|
||||
/**
|
||||
* A lightweight object which simply wraps a {@link Character} and implements {@link NodeCharacterProvider}, which
|
||||
* can be used as a key to locate a node having the same edge first character in a list of nodes using binary search.
|
||||
*
|
||||
*/
|
||||
public class NodeCharacterKey implements NodeCharacterProvider {
|
||||
|
||||
private final Character character;
|
||||
|
||||
public NodeCharacterKey(Character character) {
|
||||
this.character = character;
|
||||
}
|
||||
|
||||
@Override
|
||||
public Character getIncomingEdgeFirstCharacter() {
|
||||
return character;
|
||||
}
|
||||
}
|
||||
@ -0,0 +1,14 @@
|
||||
package org.xbib.datastructures.trie.concurrent.util;
|
||||
|
||||
/**
|
||||
* A super-interface of both {@link Node} and {@link NodeCharacterKey}
|
||||
* which, by sharing this common interface, enables binary search of nodes via
|
||||
* {@link java.util.Collections#binarySearch(java.util.List, Object, java.util.Comparator)}.
|
||||
*
|
||||
* @see NodeCharacterComparator
|
||||
* @see NodeCharacterKey
|
||||
*/
|
||||
public interface NodeCharacterProvider {
|
||||
|
||||
Character getIncomingEdgeFirstCharacter();
|
||||
}
|
||||
@ -0,0 +1,34 @@
|
||||
package org.xbib.datastructures.trie.concurrent.util;
|
||||
|
||||
import java.util.List;
|
||||
|
||||
/**
|
||||
* An interface for a factory which creates new {@link Node} objects on demand, to encapsulate specified variables.
|
||||
* Factory objects can choose to return implementations of the {@link Node} interface which are memory-optimized for
|
||||
* storing only the given variables, potentially further optimized based on variable values.
|
||||
*/
|
||||
public interface NodeFactory {
|
||||
|
||||
/**
|
||||
* Returns a new {@link Node} object which encapsulates the arguments supplied, optionally returning implementations
|
||||
* of the {@link Node} interface which are memory-optimized for storing only the supplied combination of variables,
|
||||
* potentially further optimized based on variable values.
|
||||
*
|
||||
* @param edgeCharacters Provides edge characters to be stored in the node. This is never null. In the case of
|
||||
* (re-)constructing the root node, this will contain zero characters, otherwise will always contain one or more
|
||||
* characters
|
||||
*
|
||||
* @param value An arbitrary object to associate with the node. This can be null, but it will not be null if
|
||||
* dealing with a leaf node (when childNodes will be empty)
|
||||
*
|
||||
* @param childNodes A list of child nodes to store in the node. This will never be null, but may be empty when
|
||||
* building a leaf node
|
||||
*
|
||||
* @param isRoot Indicates if this will be the root node, in which case edge characters will be non-null but empty,
|
||||
* value will be null, and child nodes will be non-null but may be empty
|
||||
*
|
||||
* @return An object implementing the {@link Node} interface which stores the given variables
|
||||
*/
|
||||
Node createNode(CharSequence edgeCharacters, Object value, List<Node> childNodes, boolean isRoot);
|
||||
|
||||
}
|
||||
@ -0,0 +1,80 @@
|
||||
package org.xbib.datastructures.trie.concurrent.util;
|
||||
|
||||
import java.util.*;
|
||||
import java.util.concurrent.atomic.AtomicReferenceArray;
|
||||
|
||||
/**
|
||||
* Static utility methods useful when implementing {@link Node}s.
|
||||
*/
|
||||
public class NodeUtil {
|
||||
|
||||
/**
|
||||
* Private constructor, not used.
|
||||
*/
|
||||
NodeUtil() {
|
||||
}
|
||||
|
||||
/**
|
||||
* Returns the index of the node in the given {@link AtomicReferenceArray} whose edge starts with the given
|
||||
* first character.
|
||||
* <p/>
|
||||
* This method expects that some constraints are enforced on the {@link AtomicReferenceArray}:
|
||||
* <ul>
|
||||
* <li>
|
||||
* The array must already be in ascending sorted order of the first character of the edge for each node
|
||||
* </li>
|
||||
* <li>
|
||||
* No entries in the array can be null
|
||||
* </li>
|
||||
* <li>
|
||||
* Any existing node in the array cannot be swapped concurrently for another unless the edge associated
|
||||
* with the other node also starts with the same first character
|
||||
* </li>
|
||||
* </ul>
|
||||
* If these constraints are enforced as expected, then this method will have deterministic behaviour even in the
|
||||
* face of concurrent modification.
|
||||
*
|
||||
* @param childNodes An {@link AtomicReferenceArray} of {@link Node} objects, which is used in accordance with
|
||||
* the constraints documented in this method
|
||||
*
|
||||
* @param edgeFirstCharacter The first character of the edge for which the associated node is required
|
||||
* @return The index of the node representing the indicated edge, or a value < 0 if no such node exists in the
|
||||
* array
|
||||
*/
|
||||
public static int binarySearchForEdge(AtomicReferenceArray<Node> childNodes, Character edgeFirstCharacter) {
|
||||
// inspired by Collections#indexedBinarySearch()
|
||||
int low = 0;
|
||||
int high = childNodes.length() - 1;
|
||||
|
||||
while (low <= high) {
|
||||
int mid = (low + high) >>> 1;
|
||||
Node midVal = childNodes.get(mid);
|
||||
int cmp = midVal.getIncomingEdgeFirstCharacter().compareTo(edgeFirstCharacter);
|
||||
|
||||
if (cmp < 0)
|
||||
low = mid + 1;
|
||||
else if (cmp > 0)
|
||||
high = mid - 1;
|
||||
else
|
||||
return mid; // key found
|
||||
}
|
||||
return -(low + 1); // key not found
|
||||
}
|
||||
|
||||
/**
|
||||
* Throws an exception if any nodes in the given list represent edges having the same first character.
|
||||
*
|
||||
* @param nodes The list of nodes to validate
|
||||
* @throws IllegalStateException If a duplicate edge is detected
|
||||
*/
|
||||
public static void ensureNoDuplicateEdges(List<Node> nodes) {
|
||||
// Sanity check that no two nodes specify an edge with the same first character...
|
||||
Set<Character> uniqueChars = new HashSet<Character>(nodes.size());
|
||||
for (Node node : nodes) {
|
||||
uniqueChars.add(node.getIncomingEdgeFirstCharacter());
|
||||
}
|
||||
if (nodes.size() != uniqueChars.size()) {
|
||||
throw new IllegalStateException("Duplicate edge detected in list of nodes supplied: " + nodes);
|
||||
}
|
||||
}
|
||||
}
|
||||
@ -0,0 +1,27 @@
|
||||
package org.xbib.datastructures.trie.concurrent.util;
|
||||
|
||||
/**
|
||||
* A dummy object which if supplied as a value for an entry in a tree.
|
||||
*/
|
||||
public class VoidValue {
|
||||
|
||||
@Override
|
||||
public int hashCode() {
|
||||
return 1;
|
||||
}
|
||||
|
||||
@Override
|
||||
public boolean equals(Object obj) {
|
||||
return obj instanceof VoidValue;
|
||||
}
|
||||
|
||||
@Override
|
||||
public String toString() {
|
||||
return "-";
|
||||
}
|
||||
|
||||
VoidValue() {
|
||||
}
|
||||
|
||||
public static final VoidValue SINGLETON = new VoidValue();
|
||||
}
|
||||
@ -0,0 +1,962 @@
|
||||
package org.xbib.datastructures.trie.concurrent;
|
||||
|
||||
import org.junit.jupiter.api.Test;
|
||||
import org.xbib.datastructures.trie.concurrent.util.DefaultCharArrayNodeFactory;
|
||||
import org.xbib.datastructures.trie.concurrent.util.DefaultCharSequenceNodeFactory;
|
||||
import org.xbib.datastructures.trie.concurrent.util.Iterables;
|
||||
import org.xbib.datastructures.trie.concurrent.util.KeyValuePair;
|
||||
import org.xbib.datastructures.trie.concurrent.util.Node;
|
||||
import org.xbib.datastructures.trie.concurrent.util.NodeFactory;
|
||||
import org.xbib.datastructures.trie.concurrent.util.VoidValue;
|
||||
|
||||
import java.util.Arrays;
|
||||
import java.util.Collections;
|
||||
|
||||
import static org.junit.jupiter.api.Assertions.assertEquals;
|
||||
import static org.junit.jupiter.api.Assertions.assertFalse;
|
||||
import static org.junit.jupiter.api.Assertions.assertNotNull;
|
||||
import static org.junit.jupiter.api.Assertions.assertNull;
|
||||
import static org.junit.jupiter.api.Assertions.assertThrows;
|
||||
import static org.junit.jupiter.api.Assertions.assertTrue;
|
||||
|
||||
public class ConcurrentRadixTreeTest {
|
||||
|
||||
private final NodeFactory nodeFactory = new DefaultCharArrayNodeFactory();
|
||||
|
||||
protected NodeFactory getNodeFactory() {
|
||||
return nodeFactory;
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testBuildTreeByHand() {
|
||||
// Build the tree by hand, as if the following strings were added: B, BA, BAN, BANDANA, BANAN, BANANA
|
||||
|
||||
// ○
|
||||
// └── ○ B (1)
|
||||
// └── ○ A (2)
|
||||
// └── ○ N (3)
|
||||
// ├── ○ AN (5)
|
||||
// │ └── ○ A (6)
|
||||
// └── ○ DANA (4)
|
||||
|
||||
final Node root, n1, n2, n3, n4, n5, n6;
|
||||
n6 = getNodeFactory().createNode("A", 6, Collections.<Node>emptyList(), false);
|
||||
n5 = getNodeFactory().createNode("AN", 5, Arrays.asList(n6), false);
|
||||
n4 = getNodeFactory().createNode("DANA", 4, Collections.<Node>emptyList(), false);
|
||||
n3 = getNodeFactory().createNode("N", 3, Arrays.asList(n4, n5), false); // note: it should sort alphabetically such that n5 is first
|
||||
n2 = getNodeFactory().createNode("A", 2, Arrays.asList(n3), false);
|
||||
n1 = getNodeFactory().createNode("B", 1, Arrays.asList(n2), false);
|
||||
//noinspection NullableProblems
|
||||
root = getNodeFactory().createNode("", null, Arrays.asList(n1), true);
|
||||
|
||||
String expected =
|
||||
"○\n" +
|
||||
"└── ○ B (1)\n" +
|
||||
" └── ○ A (2)\n" +
|
||||
" └── ○ N (3)\n" +
|
||||
" ├── ○ AN (5)\n" +
|
||||
" │ └── ○ A (6)\n" +
|
||||
" └── ○ DANA (4)\n";
|
||||
|
||||
String actual = PrettyPrinter.prettyPrint(root);
|
||||
assertEquals(expected, actual);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testPut_AddToRoot() {
|
||||
ConcurrentRadixTree<Integer> tree = new ConcurrentRadixTree<Integer>(getNodeFactory());
|
||||
tree.put("A", 1);
|
||||
String expected =
|
||||
"○\n" +
|
||||
"└── ○ A (1)\n";
|
||||
String actual = PrettyPrinter.prettyPrint(tree);
|
||||
assertEquals(expected, actual);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testPut_ChildNodeSorting() {
|
||||
ConcurrentRadixTree<Integer> tree = new ConcurrentRadixTree<Integer>(getNodeFactory());
|
||||
tree.put("B", 1);
|
||||
tree.put("A", 2);
|
||||
String expected =
|
||||
"○\n" +
|
||||
"├── ○ A (2)\n" +
|
||||
"└── ○ B (1)\n";
|
||||
String actual = PrettyPrinter.prettyPrint(tree);
|
||||
assertEquals(expected, actual);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testPut_AppendChild() {
|
||||
ConcurrentRadixTree<Integer> tree = new ConcurrentRadixTree<Integer>(getNodeFactory());
|
||||
tree.put("FOO", 1);
|
||||
tree.put("FOOBAR", 2);
|
||||
|
||||
String expected =
|
||||
"○\n" +
|
||||
"└── ○ FOO (1)\n" +
|
||||
" └── ○ BAR (2)\n";
|
||||
String actual = PrettyPrinter.prettyPrint(tree);
|
||||
assertEquals(expected, actual);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testPut_SplitEdge() {
|
||||
ConcurrentRadixTree<Integer> tree = new ConcurrentRadixTree<Integer>(getNodeFactory());
|
||||
tree.put("FOOBAR", 1);
|
||||
tree.put("FOO", 2);
|
||||
|
||||
String expected =
|
||||
"○\n" +
|
||||
"└── ○ FOO (2)\n" +
|
||||
" └── ○ BAR (1)\n";
|
||||
String actual = PrettyPrinter.prettyPrint(tree);
|
||||
assertEquals(expected, actual);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testPut_SplitWithImplicitNode() {
|
||||
ConcurrentRadixTree<Integer> tree = new ConcurrentRadixTree<Integer>(getNodeFactory());
|
||||
tree.put("FOOBAR", 1);
|
||||
tree.put("FOOD", 2);
|
||||
|
||||
String expected =
|
||||
"○\n" +
|
||||
"└── ○ FOO\n" + // We never explicitly inserted FOO
|
||||
" ├── ○ BAR (1)\n" +
|
||||
" └── ○ D (2)\n";
|
||||
String actual = PrettyPrinter.prettyPrint(tree);
|
||||
assertEquals(expected, actual);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testPut_SplitAndMove() {
|
||||
ConcurrentRadixTree<Integer> tree = new ConcurrentRadixTree<Integer>(getNodeFactory());
|
||||
tree.put("TEST", 1);
|
||||
tree.put("TEAM", 2);
|
||||
tree.put("TOAST", 3);
|
||||
|
||||
String expected =
|
||||
"○\n" +
|
||||
"└── ○ T\n" + // implicit node added automatically
|
||||
" ├── ○ E\n" + // implicit node added automatically
|
||||
" │ ├── ○ AM (2)\n" +
|
||||
" │ └── ○ ST (1)\n" +
|
||||
" └── ○ OAST (3)\n";
|
||||
String actual = PrettyPrinter.prettyPrint(tree);
|
||||
assertEquals(expected, actual);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testPut_OverwriteValue() {
|
||||
ConcurrentRadixTree<Integer> tree = new ConcurrentRadixTree<Integer>(getNodeFactory());
|
||||
|
||||
Integer existing;
|
||||
existing = tree.put("FOO", 1);
|
||||
assertNull(existing);
|
||||
existing = tree.put("FOO", 2);
|
||||
assertNotNull(existing);
|
||||
|
||||
assertEquals(Integer.valueOf(1), existing);
|
||||
assertEquals(Integer.valueOf(2), tree.getValueForExactKey("FOO"));
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testPutIfAbsent_DoNotOverwriteValue() {
|
||||
ConcurrentRadixTree<Integer> tree = new ConcurrentRadixTree<Integer>(getNodeFactory());
|
||||
|
||||
Integer existing = tree.putIfAbsent("FOO", 1);
|
||||
assertNull(existing);
|
||||
|
||||
existing = tree.putIfAbsent("FOO", 2);
|
||||
assertNotNull(existing);
|
||||
|
||||
assertEquals(Integer.valueOf(1), existing);
|
||||
assertEquals(Integer.valueOf(1), tree.getValueForExactKey("FOO"));
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testPutIfAbsent_SplitNode() {
|
||||
ConcurrentRadixTree<Integer> tree = new ConcurrentRadixTree<Integer>(getNodeFactory());
|
||||
|
||||
// ○
|
||||
// └── ○ FOO // implicit node added automatically
|
||||
// ├── ○ BAR (1)
|
||||
// └── ○ D (1)
|
||||
|
||||
Integer existing;
|
||||
existing = tree.putIfAbsent("FOOBAR", 1);
|
||||
assertNull(existing);
|
||||
existing = tree.putIfAbsent("FOOD", 1);
|
||||
assertNull(existing);
|
||||
|
||||
// This tests 'overwrite' set to true and exact match for node,
|
||||
// but no existing value to return (i.e. implicit node above)...
|
||||
|
||||
// ○
|
||||
// └── ○ FOO (2)
|
||||
// ├── ○ BAR (1)
|
||||
// └── ○ D (1)
|
||||
|
||||
existing = tree.putIfAbsent("FOO", 2);
|
||||
assertNull(existing);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testPut_VoidValue_CharArrayNodeFactory() {
|
||||
ConcurrentRadixTree<VoidValue> tree = new ConcurrentRadixTree<VoidValue>(getNodeFactory());
|
||||
tree.put("FOO", VoidValue.SINGLETON);
|
||||
tree.put("FOOBAR", VoidValue.SINGLETON);
|
||||
String expected =
|
||||
"○\n" +
|
||||
"└── ○ FOO (-)\n" +
|
||||
" └── ○ BAR (-)\n";
|
||||
String actual = PrettyPrinter.prettyPrint(tree);
|
||||
assertEquals(expected, actual);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testPut_VoidValue_CharSequenceNodeFactory() {
|
||||
ConcurrentRadixTree<VoidValue> tree = new ConcurrentRadixTree<VoidValue>(new DefaultCharSequenceNodeFactory());
|
||||
tree.put("FOO", VoidValue.SINGLETON);
|
||||
tree.put("FOOBAR", VoidValue.SINGLETON);
|
||||
String expected =
|
||||
"○\n" +
|
||||
"└── ○ FOO (-)\n" +
|
||||
" └── ○ BAR (-)\n";
|
||||
String actual = PrettyPrinter.prettyPrint(tree);
|
||||
assertEquals(expected, actual);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testPutInternal_ArgumentValidation1() {
|
||||
assertThrows(IllegalArgumentException.class, () -> {
|
||||
ConcurrentRadixTree<Integer> tree = new ConcurrentRadixTree<Integer>(getNodeFactory());
|
||||
//noinspection NullableProblems
|
||||
tree.put(null, 1);
|
||||
});
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testPutInternal_ArgumentValidation2() {
|
||||
assertThrows(IllegalArgumentException.class, () -> {
|
||||
ConcurrentRadixTree<Integer> tree = new ConcurrentRadixTree<Integer>(getNodeFactory());
|
||||
//noinspection NullableProblems
|
||||
tree.put("FOO", null);
|
||||
});
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testPutInternal_ArgumentValidation3() {
|
||||
assertThrows(IllegalArgumentException.class, () -> {
|
||||
ConcurrentRadixTree<Integer> tree = new ConcurrentRadixTree<Integer>(getNodeFactory());
|
||||
//noinspection NullableProblems
|
||||
tree.put("", 1);
|
||||
});
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testPutInternal_InvalidClassification() {
|
||||
assertThrows(IllegalStateException.class, () -> {
|
||||
// Create a dummy subclass of SearchResult which returns an INVALID classification...
|
||||
class InvalidSearchResult extends ConcurrentRadixTree.SearchResult {
|
||||
InvalidSearchResult(CharSequence key, Node nodeFound, int charsMatched, int charsMatchedInNodeFound, Node parentNode, Node parentNodesParent) {
|
||||
super(key, nodeFound, charsMatched, charsMatchedInNodeFound, parentNode, parentNodesParent);
|
||||
}
|
||||
|
||||
@Override
|
||||
protected Classification classify(CharSequence key, Node nodeFound, int charsMatched, int charsMatchedInNodeFound) {
|
||||
return Classification.INVALID;
|
||||
}
|
||||
}
|
||||
// Override searchTree() to return the InvalidSearchResult...
|
||||
ConcurrentRadixTree<Integer> tree = new ConcurrentRadixTree<Integer>(getNodeFactory()) {
|
||||
@Override
|
||||
SearchResult searchTree(CharSequence key) {
|
||||
return new InvalidSearchResult("FOO", root, 4, 4, null, null);
|
||||
|
||||
}
|
||||
};
|
||||
// We expect put() to throw an IllegalStateException
|
||||
// when it encounters the unsupported INVALID classification...
|
||||
tree.put("FOO", 1);
|
||||
});
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testSize() {
|
||||
ConcurrentRadixTree<Integer> tree = new ConcurrentRadixTree<Integer>(getNodeFactory());
|
||||
assertEquals(0, tree.size());
|
||||
tree.put("TEST", 1);
|
||||
assertEquals(1, tree.size());
|
||||
tree.put("TEAM", 2);
|
||||
assertEquals(2, tree.size());
|
||||
tree.put("TOAST", 3);
|
||||
assertEquals(3, tree.size());
|
||||
|
||||
tree.remove("FOO");
|
||||
assertEquals(3, tree.size()); // no change
|
||||
tree.remove("TOAST");
|
||||
assertEquals(2, tree.size());
|
||||
tree.remove("TEAM");
|
||||
assertEquals(1, tree.size());
|
||||
tree.remove("TEST");
|
||||
assertEquals(0, tree.size());
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testGet() {
|
||||
ConcurrentRadixTree<Integer> tree = new ConcurrentRadixTree<Integer>(getNodeFactory());
|
||||
tree.put("TEST", 1);
|
||||
tree.put("TEAM", 2);
|
||||
tree.put("TOAST", 3);
|
||||
|
||||
// ○
|
||||
// └── ○ T // implicit node added automatically
|
||||
// ├── ○ E // implicit node added automatically
|
||||
// │ ├── ○ AM (2)
|
||||
// │ └── ○ ST (1)
|
||||
// └── ○ OAST (3)
|
||||
|
||||
assertEquals(Integer.valueOf(1), tree.getValueForExactKey("TEST"));
|
||||
assertEquals(Integer.valueOf(2), tree.getValueForExactKey("TEAM"));
|
||||
assertEquals(Integer.valueOf(3), tree.getValueForExactKey("TOAST"));
|
||||
assertNull(tree.getValueForExactKey("T"));
|
||||
assertNull(tree.getValueForExactKey("TE"));
|
||||
assertNull(tree.getValueForExactKey("E")); // sanity check, no such edge from root
|
||||
assertNull(tree.getValueForExactKey("")); // sanity check, root never has a value
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testRemove_MoreThanOneChildEdge() {
|
||||
ConcurrentRadixTree<Integer> tree = new ConcurrentRadixTree<Integer>(getNodeFactory());
|
||||
tree.put("FOO", 1);
|
||||
tree.put("FOOBAR", 2);
|
||||
tree.put("FOOD", 3);
|
||||
|
||||
// ○
|
||||
// └── ○ FOO (1)
|
||||
// ├── ○ BAR (2)
|
||||
// └── ○ D (3)
|
||||
|
||||
String expected, actual;
|
||||
expected =
|
||||
"○\n" +
|
||||
"└── ○ FOO (1)\n" +
|
||||
" ├── ○ BAR (2)\n" +
|
||||
" └── ○ D (3)\n";
|
||||
actual = PrettyPrinter.prettyPrint(tree);
|
||||
assertEquals(expected, actual);
|
||||
|
||||
boolean removed = tree.remove("FOO");
|
||||
assertTrue(removed);
|
||||
|
||||
// ○
|
||||
// └── ○ FOO // value removed from FOO, but node needs to stay (as implicit node)
|
||||
// ├── ○ BAR (2)
|
||||
// └── ○ D (3)
|
||||
|
||||
expected =
|
||||
"○\n" +
|
||||
"└── ○ FOO\n" +
|
||||
" ├── ○ BAR (2)\n" +
|
||||
" └── ○ D (3)\n";
|
||||
actual = PrettyPrinter.prettyPrint(tree);
|
||||
assertEquals(expected, actual);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testRemove_ExactlyOneChildEdge() {
|
||||
ConcurrentRadixTree<Integer> tree = new ConcurrentRadixTree<Integer>(getNodeFactory());
|
||||
tree.put("FOO", 1);
|
||||
tree.put("FOOBAR", 2);
|
||||
tree.put("FOOBARBAZ", 3);
|
||||
|
||||
// ○
|
||||
// └── ○ FOO (1)
|
||||
// └── ○ BAR (2)
|
||||
// └── ○ BAZ (3)
|
||||
|
||||
|
||||
String expected, actual;
|
||||
expected =
|
||||
"○\n" +
|
||||
"└── ○ FOO (1)\n" +
|
||||
" └── ○ BAR (2)\n" +
|
||||
" └── ○ BAZ (3)\n";
|
||||
actual = PrettyPrinter.prettyPrint(tree);
|
||||
assertEquals(expected, actual);
|
||||
|
||||
boolean removed = tree.remove("FOO");
|
||||
assertTrue(removed);
|
||||
|
||||
// ○
|
||||
// └── ○ FOOBAR (2) // Edges FOO and BAR merged,
|
||||
// └── ○ BAZ (3) // and the value and child edges from BAR also copied into merged node
|
||||
|
||||
expected =
|
||||
"○\n" +
|
||||
"└── ○ FOOBAR (2)\n" +
|
||||
" └── ○ BAZ (3)\n";
|
||||
actual = PrettyPrinter.prettyPrint(tree);
|
||||
assertEquals(expected, actual);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testRemove_ZeroChildEdges_DirectChildOfRoot() {
|
||||
ConcurrentRadixTree<Integer> tree = new ConcurrentRadixTree<Integer>(getNodeFactory());
|
||||
tree.put("FOO", 1);
|
||||
tree.put("BAR", 2);
|
||||
|
||||
// ○
|
||||
// ├── ○ BAR (2)
|
||||
// └── ○ FOO (1)
|
||||
|
||||
String expected, actual;
|
||||
expected =
|
||||
"○\n" +
|
||||
"├── ○ BAR (2)\n" +
|
||||
"└── ○ FOO (1)\n";
|
||||
actual = PrettyPrinter.prettyPrint(tree);
|
||||
assertEquals(expected, actual);
|
||||
|
||||
boolean removed = tree.remove("FOO");
|
||||
assertTrue(removed);
|
||||
|
||||
// ○ // FOO removed, which involved recreating the root to change its child edges
|
||||
// └── ○ BAR (2)
|
||||
|
||||
expected =
|
||||
"○\n" +
|
||||
"└── ○ BAR (2)\n";
|
||||
actual = PrettyPrinter.prettyPrint(tree);
|
||||
assertEquals(expected, actual);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testRemove_LastRemainingKey() {
|
||||
ConcurrentRadixTree<Integer> tree = new ConcurrentRadixTree<Integer>(getNodeFactory());
|
||||
tree.put("FOO", 1);
|
||||
|
||||
// ○
|
||||
// └── ○ FOO (1)
|
||||
|
||||
String expected, actual;
|
||||
expected =
|
||||
"○\n" +
|
||||
"└── ○ FOO (1)\n";
|
||||
actual = PrettyPrinter.prettyPrint(tree);
|
||||
assertEquals(expected, actual);
|
||||
|
||||
boolean removed = tree.remove("FOO");
|
||||
assertTrue(removed);
|
||||
|
||||
// ○ // FOO removed, which involved recreating the root with no remaining edges
|
||||
|
||||
expected =
|
||||
"○\n";
|
||||
actual = PrettyPrinter.prettyPrint(tree);
|
||||
assertEquals(expected, actual);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testRemove_ZeroChildEdges_OneStepFromRoot() {
|
||||
ConcurrentRadixTree<Integer> tree = new ConcurrentRadixTree<Integer>(getNodeFactory());
|
||||
tree.put("FOO", 1);
|
||||
tree.put("FOOBAR", 2);
|
||||
|
||||
// ○
|
||||
// └── ○ FOO (1)
|
||||
// └── ○ BAR (2)
|
||||
|
||||
|
||||
String expected, actual;
|
||||
expected =
|
||||
"○\n" +
|
||||
"└── ○ FOO (1)\n" +
|
||||
" └── ○ BAR (2)\n";
|
||||
actual = PrettyPrinter.prettyPrint(tree);
|
||||
assertEquals(expected, actual);
|
||||
|
||||
boolean removed = tree.remove("FOOBAR");
|
||||
assertTrue(removed);
|
||||
|
||||
// ○
|
||||
// └── ○ FOO (1) // BAR removed, which involved recreating FOO and re-adding it to root node
|
||||
|
||||
expected =
|
||||
"○\n" +
|
||||
"└── ○ FOO (1)\n";
|
||||
actual = PrettyPrinter.prettyPrint(tree);
|
||||
assertEquals(expected, actual);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testRemove_ZeroChildEdges_SeveralStepsFromRoot() {
|
||||
ConcurrentRadixTree<Integer> tree = new ConcurrentRadixTree<Integer>(getNodeFactory());
|
||||
tree.put("FOO", 1);
|
||||
tree.put("FOOBAR", 2);
|
||||
tree.put("FOOBARBAZ", 3);
|
||||
|
||||
// ○
|
||||
// └── ○ FOO (1)
|
||||
// └── ○ BAR (2)
|
||||
// └── ○ BAZ (3)
|
||||
|
||||
|
||||
String expected, actual;
|
||||
expected =
|
||||
"○\n" +
|
||||
"└── ○ FOO (1)\n" +
|
||||
" └── ○ BAR (2)\n" +
|
||||
" └── ○ BAZ (3)\n";
|
||||
actual = PrettyPrinter.prettyPrint(tree);
|
||||
assertEquals(expected, actual);
|
||||
|
||||
boolean removed = tree.remove("FOOBARBAZ");
|
||||
assertTrue(removed);
|
||||
|
||||
// ○
|
||||
// └── ○ FOO (1)
|
||||
// └── ○ BAR (2) // BAZ removed, which involved recreating BAR and re-adding it to its parent FOO
|
||||
|
||||
expected =
|
||||
"○\n" +
|
||||
"└── ○ FOO (1)\n" +
|
||||
" └── ○ BAR (2)\n";
|
||||
actual = PrettyPrinter.prettyPrint(tree);
|
||||
assertEquals(expected, actual);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testRemove_DoNotRemoveSplitNode() {
|
||||
ConcurrentRadixTree<Integer> tree = new ConcurrentRadixTree<Integer>(getNodeFactory());
|
||||
tree.put("FOOBAR", 1);
|
||||
tree.put("FOOD", 2);
|
||||
|
||||
// ○
|
||||
// └── ○ FOO // implicit node added automatically
|
||||
// ├── ○ BAR (1)
|
||||
// └── ○ D (2)
|
||||
|
||||
|
||||
String expected, actual;
|
||||
expected =
|
||||
"○\n" +
|
||||
"└── ○ FOO\n" +
|
||||
" ├── ○ BAR (1)\n" +
|
||||
" └── ○ D (2)\n";
|
||||
actual = PrettyPrinter.prettyPrint(tree);
|
||||
assertEquals(expected, actual);
|
||||
|
||||
boolean removed = tree.remove("FOO");
|
||||
assertFalse(removed);
|
||||
|
||||
expected =
|
||||
"○\n" +
|
||||
"└── ○ FOO\n" + // we expect no change
|
||||
" ├── ○ BAR (1)\n" +
|
||||
" └── ○ D (2)\n";
|
||||
actual = PrettyPrinter.prettyPrint(tree);
|
||||
assertEquals(expected, actual);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testRemove_MergeSplitNode() {
|
||||
ConcurrentRadixTree<Integer> tree = new ConcurrentRadixTree<Integer>(getNodeFactory());
|
||||
tree.put("TEST", 1);
|
||||
tree.put("TEAM", 2);
|
||||
tree.put("TOAST", 3);
|
||||
|
||||
String expected, actual;
|
||||
expected =
|
||||
"○\n" +
|
||||
"└── ○ T\n" +
|
||||
" ├── ○ E\n" +
|
||||
" │ ├── ○ AM (2)\n" +
|
||||
" │ └── ○ ST (1)\n" +
|
||||
" └── ○ OAST (3)\n";
|
||||
actual = PrettyPrinter.prettyPrint(tree);
|
||||
assertEquals(expected, actual);
|
||||
|
||||
boolean removed = tree.remove("TEST");
|
||||
assertTrue(removed);
|
||||
|
||||
expected =
|
||||
"○\n" +
|
||||
"└── ○ T\n" +
|
||||
" ├── ○ EAM (2)\n" +
|
||||
" └── ○ OAST (3)\n";
|
||||
actual = PrettyPrinter.prettyPrint(tree);
|
||||
assertEquals(expected, actual);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testRemove_DoNotMergeSplitNodeWithValue() {
|
||||
ConcurrentRadixTree<Integer> tree = new ConcurrentRadixTree<Integer>(getNodeFactory());
|
||||
tree.put("TEST", 1);
|
||||
tree.put("TEAM", 2);
|
||||
tree.put("TOAST", 3);
|
||||
tree.put("TE", 4);
|
||||
|
||||
String expected, actual;
|
||||
expected =
|
||||
"○\n" +
|
||||
"└── ○ T\n" +
|
||||
" ├── ○ E (4)\n" +
|
||||
" │ ├── ○ AM (2)\n" +
|
||||
" │ └── ○ ST (1)\n" +
|
||||
" └── ○ OAST (3)\n";
|
||||
actual = PrettyPrinter.prettyPrint(tree);
|
||||
assertEquals(expected, actual);
|
||||
|
||||
boolean removed = tree.remove("TEST");
|
||||
assertTrue(removed);
|
||||
|
||||
expected =
|
||||
"○\n" +
|
||||
"└── ○ T\n" +
|
||||
" ├── ○ E (4)\n" +
|
||||
" │ └── ○ AM (2)\n" +
|
||||
" └── ○ OAST (3)\n";
|
||||
actual = PrettyPrinter.prettyPrint(tree);
|
||||
assertEquals(expected, actual);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testRemove_NoSuchKey() {
|
||||
ConcurrentRadixTree<Integer> tree = new ConcurrentRadixTree<Integer>(getNodeFactory());
|
||||
tree.put("FOO", 1);
|
||||
tree.put("BAR", 2);
|
||||
|
||||
String expected, actual;
|
||||
expected =
|
||||
"○\n" +
|
||||
"├── ○ BAR (2)\n" +
|
||||
"└── ○ FOO (1)\n";
|
||||
actual = PrettyPrinter.prettyPrint(tree);
|
||||
assertEquals(expected, actual);
|
||||
|
||||
boolean removed = tree.remove("BAZ");
|
||||
assertFalse(removed);
|
||||
|
||||
expected =
|
||||
"○\n" + // we expect no change
|
||||
"├── ○ BAR (2)\n" +
|
||||
"└── ○ FOO (1)\n";
|
||||
actual = PrettyPrinter.prettyPrint(tree);
|
||||
assertEquals(expected, actual);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testGetKeysForPrefix() {
|
||||
ConcurrentRadixTree<Integer> tree = new ConcurrentRadixTree<Integer>(getNodeFactory());
|
||||
tree.put("TEST", 1);
|
||||
tree.put("TEAM", 2);
|
||||
tree.put("TOAST", 3);
|
||||
tree.put("TEA", 4);
|
||||
tree.put("COFFEE", 5);
|
||||
|
||||
// ○
|
||||
// ├── ○ COFFEE (5)
|
||||
// └── ○ T
|
||||
// ├── ○ E
|
||||
// │ ├── ○ A (4)
|
||||
// │ │ └── ○ M (2)
|
||||
// │ └── ○ ST (1)
|
||||
// └── ○ OAST (3)
|
||||
|
||||
assertEquals("[COFFEE, TEA, TEAM, TEST, TOAST]", Iterables.toString(tree.getKeysStartingWith("")));
|
||||
assertEquals("[COFFEE]", Iterables.toString(tree.getKeysStartingWith("C")));
|
||||
assertEquals("[COFFEE]", Iterables.toString(tree.getKeysStartingWith("COFFEE")));
|
||||
assertEquals("[]", Iterables.toString(tree.getKeysStartingWith("COFFEES")));
|
||||
assertEquals("[TEA, TEAM, TEST, TOAST]", Iterables.toString(tree.getKeysStartingWith("T")));
|
||||
assertEquals("[TEA, TEAM, TEST]", Iterables.toString(tree.getKeysStartingWith("TE")));
|
||||
assertEquals("[TEA, TEAM]", Iterables.toString(tree.getKeysStartingWith("TEA")));
|
||||
assertEquals("[TOAST]", Iterables.toString(tree.getKeysStartingWith("TO")));
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testGetClosestKeys() {
|
||||
ConcurrentRadixTree<Integer> tree = new ConcurrentRadixTree<Integer>(getNodeFactory());
|
||||
tree.put("COD", 1);
|
||||
tree.put("CODFISH", 2);
|
||||
tree.put("COFFEE", 3);
|
||||
|
||||
// ○
|
||||
// └── ○ CO
|
||||
// ├── ○ D (1)
|
||||
// │ └── ○ FISH (2)
|
||||
// └── ○ FFEE (3)
|
||||
|
||||
assertEquals("[COD, CODFISH, COFFEE]", Iterables.toString(tree.getClosestKeys("COW")));
|
||||
assertEquals("[COD, CODFISH, COFFEE]", Iterables.toString(tree.getClosestKeys("CX")));
|
||||
assertEquals("[COD, CODFISH]", Iterables.toString(tree.getClosestKeys("COD")));
|
||||
assertEquals("[COFFEE]", Iterables.toString(tree.getClosestKeys("COF")));
|
||||
assertEquals("[]", Iterables.toString(tree.getClosestKeys("DO")));
|
||||
assertEquals("[CODFISH]", Iterables.toString(tree.getClosestKeys("CODFISHES")));
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testGetValuesForClosestKeys() {
|
||||
ConcurrentRadixTree<Integer> tree = new ConcurrentRadixTree<Integer>(getNodeFactory());
|
||||
tree.put("COD", 1);
|
||||
tree.put("CODFISH", 2);
|
||||
tree.put("COFFEE", 3);
|
||||
|
||||
// ○
|
||||
// └── ○ CO
|
||||
// ├── ○ D (1)
|
||||
// │ └── ○ FISH (2)
|
||||
// └── ○ FFEE (3)
|
||||
|
||||
assertEquals("[1, 2, 3]", Iterables.toString(tree.getValuesForClosestKeys("COW")));
|
||||
assertEquals("[1, 2, 3]", Iterables.toString(tree.getValuesForClosestKeys("CX")));
|
||||
assertEquals("[1, 2]", Iterables.toString(tree.getValuesForClosestKeys("COD")));
|
||||
assertEquals("[3]", Iterables.toString(tree.getValuesForClosestKeys("COF")));
|
||||
assertEquals("[]", Iterables.toString(tree.getValuesForClosestKeys("DO")));
|
||||
assertEquals("[2]", Iterables.toString(tree.getValuesForClosestKeys("CODFISHES")));
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testGetKeyValuePairsForClosestKeys() {
|
||||
ConcurrentRadixTree<Integer> tree = new ConcurrentRadixTree<Integer>(getNodeFactory());
|
||||
tree.put("COD", 1);
|
||||
tree.put("CODFISH", 2);
|
||||
tree.put("COFFEE", 3);
|
||||
|
||||
// ○
|
||||
// └── ○ CO
|
||||
// ├── ○ D (1)
|
||||
// │ └── ○ FISH (2)
|
||||
// └── ○ FFEE (3)
|
||||
|
||||
assertEquals("[(COD, 1), (CODFISH, 2), (COFFEE, 3)]", Iterables.toString(tree.getKeyValuePairsForClosestKeys("COW")));
|
||||
assertEquals("[(COD, 1), (CODFISH, 2), (COFFEE, 3)]", Iterables.toString(tree.getKeyValuePairsForClosestKeys("CX")));
|
||||
assertEquals("[(COD, 1), (CODFISH, 2)]", Iterables.toString(tree.getKeyValuePairsForClosestKeys("COD")));
|
||||
assertEquals("[(COFFEE, 3)]", Iterables.toString(tree.getKeyValuePairsForClosestKeys("COF")));
|
||||
assertEquals("[]", Iterables.toString(tree.getKeyValuePairsForClosestKeys("DO")));
|
||||
assertEquals("[(CODFISH, 2)]", Iterables.toString(tree.getKeyValuePairsForClosestKeys("CODFISHES")));
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testKeyValuePair_Accessor() {
|
||||
KeyValuePair<Integer> pair = new ConcurrentRadixTree.KeyValuePairImpl<Integer>("FOO", 5);
|
||||
assertEquals(pair.getKey(), "FOO");
|
||||
assertEquals(pair.getValue(), Integer.valueOf(5));
|
||||
assertEquals("(FOO, 5)", pair.toString());
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testKeyValuePair_EqualsAndHashCode() {
|
||||
KeyValuePair<Integer> pair1 = new ConcurrentRadixTree.KeyValuePairImpl<Integer>("FOO", 5);
|
||||
KeyValuePair<Integer> pair2 = new ConcurrentRadixTree.KeyValuePairImpl<Integer>("FOO", 6);
|
||||
KeyValuePair<Integer> pair3 = new ConcurrentRadixTree.KeyValuePairImpl<Integer>("BAR", 5);
|
||||
assertTrue(pair1.equals(pair1));
|
||||
assertTrue(pair1.equals(pair2));
|
||||
assertFalse(pair1.equals(pair3));
|
||||
//noinspection NullableProblems,ObjectEqualsNull
|
||||
assertFalse(pair1.equals(null));
|
||||
//noinspection EqualsBetweenInconvertibleTypes
|
||||
assertFalse(pair1.equals("FOO"));
|
||||
assertTrue(pair1.hashCode() == pair2.hashCode());
|
||||
assertFalse(pair1.hashCode() == pair3.hashCode());
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testGetValuesForPrefix() {
|
||||
ConcurrentRadixTree<Integer> tree = new ConcurrentRadixTree<Integer>(getNodeFactory());
|
||||
tree.put("TEST", 1);
|
||||
tree.put("TEAM", 2);
|
||||
tree.put("TOAST", 3);
|
||||
tree.put("TEA", 4);
|
||||
tree.put("COFFEE", 5);
|
||||
|
||||
// ○
|
||||
// ├── ○ COFFEE (5)
|
||||
// └── ○ T
|
||||
// ├── ○ E
|
||||
// │ ├── ○ A (4)
|
||||
// │ │ └── ○ M (2)
|
||||
// │ └── ○ ST (1)
|
||||
// └── ○ OAST (3)
|
||||
|
||||
assertEquals("[5, 4, 2, 1, 3]", Iterables.toString(tree.getValuesForKeysStartingWith("")));
|
||||
assertEquals("[5]", Iterables.toString(tree.getValuesForKeysStartingWith("C")));
|
||||
assertEquals("[5]", Iterables.toString(tree.getValuesForKeysStartingWith("COFFEE")));
|
||||
assertEquals("[]", Iterables.toString(tree.getValuesForKeysStartingWith("COFFEES")));
|
||||
assertEquals("[4, 2, 1, 3]", Iterables.toString(tree.getValuesForKeysStartingWith("T")));
|
||||
assertEquals("[4, 2, 1]", Iterables.toString(tree.getValuesForKeysStartingWith("TE")));
|
||||
assertEquals("[4, 2]", Iterables.toString(tree.getValuesForKeysStartingWith("TEA")));
|
||||
assertEquals("[3]", Iterables.toString(tree.getValuesForKeysStartingWith("TO")));
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testGetKeyValuePairsForPrefix() {
|
||||
ConcurrentRadixTree<Integer> tree = new ConcurrentRadixTree<Integer>(getNodeFactory());
|
||||
tree.put("TEST", 1);
|
||||
tree.put("TEAM", 2);
|
||||
tree.put("TOAST", 3);
|
||||
tree.put("TEA", 4);
|
||||
tree.put("COFFEE", 5);
|
||||
|
||||
// ○
|
||||
// ├── ○ COFFEE (5)
|
||||
// └── ○ T
|
||||
// ├── ○ E
|
||||
// │ ├── ○ A (4)
|
||||
// │ │ └── ○ M (2)
|
||||
// │ └── ○ ST (1)
|
||||
// └── ○ OAST (3)
|
||||
|
||||
assertEquals("[(COFFEE, 5), (TEA, 4), (TEAM, 2), (TEST, 1), (TOAST, 3)]", Iterables.toString(tree.getKeyValuePairsForKeysStartingWith("")));
|
||||
assertEquals("[(COFFEE, 5)]", Iterables.toString(tree.getKeyValuePairsForKeysStartingWith("C")));
|
||||
assertEquals("[(COFFEE, 5)]", Iterables.toString(tree.getKeyValuePairsForKeysStartingWith("COFFEE")));
|
||||
assertEquals("[]", Iterables.toString(tree.getKeyValuePairsForKeysStartingWith("COFFEES")));
|
||||
assertEquals("[(TEA, 4), (TEAM, 2), (TEST, 1), (TOAST, 3)]", Iterables.toString(tree.getKeyValuePairsForKeysStartingWith("T")));
|
||||
assertEquals("[(TEA, 4), (TEAM, 2), (TEST, 1)]", Iterables.toString(tree.getKeyValuePairsForKeysStartingWith("TE")));
|
||||
assertEquals("[(TEA, 4), (TEAM, 2)]", Iterables.toString(tree.getKeyValuePairsForKeysStartingWith("TEA")));
|
||||
assertEquals("[(TOAST, 3)]", Iterables.toString(tree.getKeyValuePairsForKeysStartingWith("TO")));
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testRemove_ArgumentValidation() {
|
||||
assertThrows(IllegalArgumentException.class, () -> {
|
||||
ConcurrentRadixTree<Integer> tree = new ConcurrentRadixTree<Integer>(getNodeFactory());
|
||||
//noinspection NullableProblems
|
||||
tree.remove(null);
|
||||
});
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testSearchTree() {
|
||||
ConcurrentRadixTree<Integer> tree = new ConcurrentRadixTree<Integer>(getNodeFactory());
|
||||
// Build the tree by hand, as if the following strings were added: B, BA, BAN, BANDANA, BANAN, BANANA
|
||||
|
||||
// ○
|
||||
// └── ○ B (1)
|
||||
// └── ○ A (2)
|
||||
// └── ○ N (3)
|
||||
// ├── ○ AN (5)
|
||||
// │ └── ○ A (6)
|
||||
// └── ○ DANA (4)
|
||||
|
||||
final Node root, n1, n2, n3, n4, n5, n6;
|
||||
n6 = getNodeFactory().createNode("A", 6, Collections.<Node>emptyList(), false);
|
||||
n5 = getNodeFactory().createNode("AN", 5, Arrays.asList(n6), false);
|
||||
n4 = getNodeFactory().createNode("DANA", 4, Collections.<Node>emptyList(), false);
|
||||
n3 = getNodeFactory().createNode("N", 3, Arrays.asList(n4, n5), false); // note: it should sort these such that n5 is first
|
||||
n2 = getNodeFactory().createNode("A", 2, Arrays.asList(n3), false);
|
||||
n1 = getNodeFactory().createNode("B", 1, Arrays.asList(n2), false);
|
||||
//noinspection NullableProblems
|
||||
root = getNodeFactory().createNode("", null, Arrays.asList(n1), true);
|
||||
|
||||
// Overwrite the tree's default root with the one built by hand...
|
||||
tree.root = root;
|
||||
|
||||
// Sanity checks to assert that we built tree as expected....
|
||||
String expected =
|
||||
"○\n" +
|
||||
"└── ○ B (1)\n" +
|
||||
" └── ○ A (2)\n" +
|
||||
" └── ○ N (3)\n" +
|
||||
" ├── ○ AN (5)\n" +
|
||||
" │ └── ○ A (6)\n" +
|
||||
" └── ○ DANA (4)\n";
|
||||
|
||||
assertEquals(expected, PrettyPrinter.prettyPrint(tree));
|
||||
assertEquals(2, n3.getOutgoingEdges().size());
|
||||
assertTrue(n3.getOutgoingEdges().contains(n4));
|
||||
assertTrue(n3.getOutgoingEdges().contains(n5));
|
||||
|
||||
// Search for non-existing node. Should return root, with null parent, 0 charsMatched...
|
||||
assertEquals(tree.root, tree.searchTree("Z").nodeFound);
|
||||
assertNull(tree.searchTree("Z").parentNode);
|
||||
assertNull(tree.searchTree("Z").parentNodesParent);
|
||||
assertEquals(0, tree.searchTree("Z").charsMatched);
|
||||
|
||||
// Search for first child node "B". Should return n1, parent should be root, 1 charsMatched...
|
||||
assertEquals(n1, tree.searchTree("B").nodeFound);
|
||||
assertEquals(tree.root, tree.searchTree("B").parentNode);
|
||||
assertEquals(null, tree.searchTree("B").parentNodesParent);
|
||||
assertEquals(1, tree.searchTree("B").charsMatched);
|
||||
|
||||
// Search for node with split and multi-char child node at "BAN". Should return n3, parent n2, 3 charsMatched...
|
||||
assertEquals(n3, tree.searchTree("BAN").nodeFound);
|
||||
assertEquals(n2, tree.searchTree("BAN").parentNode);
|
||||
assertEquals(n1, tree.searchTree("BAN").parentNodesParent);
|
||||
assertEquals(3, tree.searchTree("BAN").charsMatched);
|
||||
|
||||
// Search for node with multi-char label (exact match) at "BANAN". Should return n5, parent n3, 5 charsMatched...
|
||||
assertEquals(n5, tree.searchTree("BANAN").nodeFound);
|
||||
assertEquals(n3, tree.searchTree("BANAN").parentNode);
|
||||
assertEquals(n2, tree.searchTree("BANAN").parentNodesParent);
|
||||
assertEquals(5, tree.searchTree("BANAN").charsMatched);
|
||||
|
||||
// Search for node with multi-char label (inexact match) at "BANA". Should return n5, parent n3, 4 charsMatched...
|
||||
assertEquals(n5, tree.searchTree("BANA").nodeFound);
|
||||
assertEquals(n3, tree.searchTree("BANA").parentNode);
|
||||
assertEquals(n2, tree.searchTree("BANA").parentNodesParent);
|
||||
assertEquals(4, tree.searchTree("BANA").charsMatched);
|
||||
|
||||
// Search for the last node in "BANANA". Should return n6, parent n5, 6 charsMatched...
|
||||
assertEquals(n6, tree.searchTree("BANANA").nodeFound);
|
||||
assertEquals(n5, tree.searchTree("BANANA").parentNode);
|
||||
assertEquals(n3, tree.searchTree("BANANA").parentNodesParent);
|
||||
assertEquals(6, tree.searchTree("BANANA").charsMatched);
|
||||
|
||||
// Search for string longer than anything in tree, differing after leaf node "BANANA".
|
||||
// Should return n6, parent n5, 6 chars matched...
|
||||
assertEquals(n6, tree.searchTree("BANANAS").nodeFound);
|
||||
assertEquals(n5, tree.searchTree("BANANAS").parentNode);
|
||||
assertEquals(n3, tree.searchTree("BANANAS").parentNodesParent);
|
||||
assertEquals(6, tree.searchTree("BANANAS").charsMatched);
|
||||
|
||||
// Search for string longer than anything in tree, differing before split at "BAN".
|
||||
// Should return n2, parent n1, 2 chars matched...
|
||||
assertEquals(n2, tree.searchTree("BAR").nodeFound);
|
||||
assertEquals(n1, tree.searchTree("BAR").parentNode);
|
||||
assertEquals(tree.root, tree.searchTree("BAR").parentNodesParent);
|
||||
assertEquals(2, tree.searchTree("BAR").charsMatched);
|
||||
|
||||
// Search for string longer than anything in tree, differing immediately after split at "BAN".
|
||||
// Should return n3, parent n2, 3 chars matched...
|
||||
assertEquals(n3, tree.searchTree("BANS").nodeFound);
|
||||
assertEquals(n2, tree.searchTree("BANS").parentNode);
|
||||
assertEquals(n1, tree.searchTree("BANS").parentNodesParent);
|
||||
assertEquals(3, tree.searchTree("BANS").charsMatched);
|
||||
|
||||
// Search for string longer than anything in tree, differing in multi-char node "BANDANA".
|
||||
// Should return n4, parent n3, 5 chars matched...
|
||||
assertEquals(n4, tree.searchTree("BANDAIDS").nodeFound);
|
||||
assertEquals(n3, tree.searchTree("BANDAIDS").parentNode);
|
||||
assertEquals(n2, tree.searchTree("BANDAIDS").parentNodesParent);
|
||||
assertEquals(5, tree.searchTree("BANDAIDS").charsMatched);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testSearchResult_FailureToClassify1() {
|
||||
assertThrows(IllegalStateException.class, () -> {
|
||||
// Testing the various (unlikely) ways to fall through classification to have the exception thrown...
|
||||
new ConcurrentRadixTree.SearchResult("DUMMY", null, 70, 70, null, null);
|
||||
});
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testSearchResult_FailureToClassify2() {
|
||||
assertThrows(IllegalStateException.class, () -> {
|
||||
// Testing the various (unlikely) ways to fall through classification to have the exception thrown...
|
||||
Node dummyNodeFound = getNodeFactory().createNode("DUMMY", 1, Collections.<Node>emptyList(), false);
|
||||
new ConcurrentRadixTree.SearchResult("DUMMY", dummyNodeFound, 5, 70, null, null);
|
||||
});
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testSearchResult_FailureToClassify3() {
|
||||
assertThrows(IllegalStateException.class, () ->{
|
||||
// Testing the various (unlikely) ways to fall through classification to have the exception thrown...
|
||||
Node dummyNodeFound = getNodeFactory().createNode("DUMMY", 1, Collections.<Node>emptyList(), false);
|
||||
new ConcurrentRadixTree.SearchResult("DUMMY", dummyNodeFound, 4, 70, null, null);
|
||||
});
|
||||
}
|
||||
}
|
||||
@ -0,0 +1,94 @@
|
||||
package org.xbib.datastructures.trie.concurrent;
|
||||
|
||||
import org.xbib.datastructures.trie.concurrent.util.Node;
|
||||
|
||||
import java.io.IOException;
|
||||
import java.util.List;
|
||||
|
||||
/**
|
||||
* Utility methods to generate semi-graphical string representations of trees.
|
||||
*/
|
||||
public class PrettyPrinter {
|
||||
|
||||
/**
|
||||
* Private constructor, not used.
|
||||
*/
|
||||
PrettyPrinter() {
|
||||
}
|
||||
|
||||
/**
|
||||
* Generates a semi-graphical string representation of a given tree.
|
||||
* <p/>
|
||||
* Example output:<br/>
|
||||
* <pre>
|
||||
* ○
|
||||
* └── ○ B (1)
|
||||
* └── ○ A (2)
|
||||
* └── ○ N (3)
|
||||
* ├── ○ AN (5)
|
||||
* │ └── ○ A (6)
|
||||
* └── ○ DANA (4)
|
||||
* </pre>
|
||||
*
|
||||
* @param tree The tree for which the semi-graphical representation should be generated
|
||||
* @return A semi-graphical string representation of the tree
|
||||
*/
|
||||
public static String prettyPrint(ConcurrentRadixTree<?> tree) {
|
||||
return prettyPrint(tree.getNode());
|
||||
}
|
||||
|
||||
public static String prettyPrint(Node node) {
|
||||
StringBuilder sb = new StringBuilder();
|
||||
prettyPrint(node, sb, "", true, true);
|
||||
return sb.toString();
|
||||
}
|
||||
|
||||
/**
|
||||
* Generates a semi-graphical string representation of a given tree, writing it to a given {@link Appendable}.
|
||||
* <p/>
|
||||
* Example output:<br/>
|
||||
* <pre>
|
||||
* ○
|
||||
* └── ○ B (1)
|
||||
* └── ○ A (2)
|
||||
* └── ○ N (3)
|
||||
* ├── ○ AN (5)
|
||||
* │ └── ○ A (6)
|
||||
* └── ○ DANA (4)
|
||||
* </pre>
|
||||
*
|
||||
* @param tree The tree for which the semi-graphical representation should be generated
|
||||
* @param appendable The object to which the tree should be written
|
||||
*/
|
||||
public static void prettyPrint(ConcurrentRadixTree<?> tree, Appendable appendable) {
|
||||
prettyPrint(tree.getNode(), appendable, "", true, true);
|
||||
}
|
||||
|
||||
static void prettyPrint(Node node, Appendable sb, String prefix, boolean isTail, boolean isRoot) {
|
||||
try {
|
||||
StringBuilder label = new StringBuilder();
|
||||
if (isRoot) {
|
||||
label.append("○");
|
||||
if (node.getIncomingEdge().length() > 0) {
|
||||
label.append(" ");
|
||||
}
|
||||
}
|
||||
label.append(node.getIncomingEdge());
|
||||
if (node.getValue() != null) {
|
||||
label.append(" (").append(node.getValue()).append(")");
|
||||
}
|
||||
sb.append(prefix).append(isTail ? isRoot ? "" : "└── ○ " : "├── ○ ").append(label).append("\n");
|
||||
List<Node> children = node.getOutgoingEdges();
|
||||
for (int i = 0; i < children.size() - 1; i++) {
|
||||
prettyPrint(children.get(i), sb, prefix + (isTail ? isRoot ? "" : " " : "│ "), false, false);
|
||||
}
|
||||
if (!children.isEmpty()) {
|
||||
prettyPrint(children.get(children.size() - 1), sb, prefix + (isTail ? isRoot ? "" : " " : "│ "), true, false);
|
||||
}
|
||||
}
|
||||
catch (IOException ioException) {
|
||||
// Rethrow the checked exception as a runtime exception...
|
||||
throw new IllegalStateException(ioException);
|
||||
}
|
||||
}
|
||||
}
|
||||
@ -0,0 +1,26 @@
|
||||
package org.xbib.datastructures.trie.regex;
|
||||
|
||||
import org.junit.jupiter.api.Test;
|
||||
|
||||
import java.util.LinkedList;
|
||||
import java.util.List;
|
||||
|
||||
import static org.junit.jupiter.api.Assertions.assertEquals;
|
||||
import static org.junit.jupiter.api.Assertions.assertNull;
|
||||
|
||||
public class RegexTrieTest {
|
||||
|
||||
@Test
|
||||
public void testRegexTrie() {
|
||||
List<List<String>> captures = new LinkedList<>();
|
||||
RegexTrie<Integer> trie = new RegexTrie<>();
|
||||
trie.put(2, List.of("a", ""));
|
||||
trie.put(4, List.of("a", "b"));
|
||||
assertEquals(2, trie.resolve(captures, List.of("a", "c", "e")));
|
||||
// returns 2. captures is now [[], ["c"], ["e"]]
|
||||
assertEquals(4, trie.resolve(captures, List.of("a", "b")));
|
||||
// returns 4. captures is now [[], []]
|
||||
assertNull(trie.resolve(captures, List.of("a", "b", "c")));
|
||||
// returns null. captures is now [[], []]
|
||||
}
|
||||
}
|
||||
Loading…
Reference in New Issue