refactor property placeholder resolution, check BytesStreamOutput for length limit

This commit is contained in:
Jörg Prante 2016-11-19 19:00:26 +01:00
parent 8d157d9192
commit 418524b427
6 changed files with 167 additions and 152 deletions

View file

@ -4,6 +4,8 @@ image:https://api.travis-ci.org/xbib/content.svg[title="Build status", link="htt
image:https://img.shields.io/sonar/http/nemo.sonarqube.com/org.xbib%3Acontent/coverage.svg?style=flat-square[title="Coverage", link="https://sonarqube.com/dashboard/index?id=org.xbib%3Acontent"]
image:https://maven-badges.herokuapp.com/maven-central/org.xbib/content/badge.svg[title="Maven Central", link="http://search.maven.org/#search%7Cga%7C1%7Cxbib%20content"]
image:https://img.shields.io/badge/License-Apache%202.0-blue.svg[title="Apache License 2.0", link="https://opensource.org/licenses/Apache-2.0"]
image:https://img.shields.io/twitter/url/https/twitter.com/xbib.svg?style=social&label=Follow%20%40xbib[title="Twitter", link="https://twitter.com/xbib"]
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This is a Java library for processing structured data ("content") in the most popular formats, such as
JSON, SMILE-JSON, YAML, XML, CSV, and also semantic descriptions in RDF (N-Triples, Turtle, RDF/XML).

View file

@ -14,7 +14,7 @@ ext {
allprojects {
group = 'org.xbib'
version = '1.0.5'
version = '1.0.6'
apply plugin: 'java'
apply plugin: 'maven'

View file

@ -96,6 +96,9 @@ public class BytesStreamOutput extends OutputStream {
if (length == 0) {
return;
}
if ((long)count + length > Integer.MAX_VALUE) {
throw new IllegalArgumentException("overflow, stream output larger than " + Integer.MAX_VALUE);
}
int newcount = count + length;
if (newcount > buf.length) {
buf = Arrays.copyOf(buf, oversize(newcount));

View file

@ -0,0 +1,16 @@
package org.xbib.content.settings;
/**
* Strategy interface used to resolve replacement values for placeholders contained in Strings.
*/
@FunctionalInterface
public interface PlaceholderResolver {
/**
* Resolves the supplied placeholder name into the replacement value.
*
* @param placeholderName the name of the placeholder to resolve.
* @return the replacement value or <code>null</code> if no replacement is to be made.
*/
String resolvePlaceholder(String placeholderName);
}

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@ -0,0 +1,120 @@
package org.xbib.content.settings;
import java.util.HashSet;
import java.util.Set;
/**
*
*/
public class PropertyPlaceholder {
private final String placeholderPrefix;
private final String placeholderSuffix;
private final boolean ignoreUnresolvablePlaceholders;
/**
* Creates a new <code>PropertyPlaceholderHelper</code> that uses the supplied prefix and suffix.
*
* @param placeholderPrefix the prefix that denotes the start of a placeholder.
* @param placeholderSuffix the suffix that denotes the end of a placeholder.
* @param ignoreUnresolvablePlaceholders indicates whether unresolvable placeholders should be ignored
* (<code>true</code>) or cause an exception (<code>false</code>).
*/
public PropertyPlaceholder(String placeholderPrefix, String placeholderSuffix,
boolean ignoreUnresolvablePlaceholders) {
this.placeholderPrefix = placeholderPrefix;
this.placeholderSuffix = placeholderSuffix;
this.ignoreUnresolvablePlaceholders = ignoreUnresolvablePlaceholders;
}
/**
* Replaces all placeholders of format <code>${name}</code> with the value returned from the supplied {@link
* PlaceholderResolver}.
*
* @param value the value containing the placeholders to be replaced.
* @param placeholderResolver the <code>PlaceholderResolver</code> to use for replacement.
* @return the supplied value with placeholders replaced inline.
*/
public String replacePlaceholders(String value, PlaceholderResolver placeholderResolver) {
return parseStringValue(value, placeholderResolver, new HashSet<String>());
}
protected String parseStringValue(String strVal, PlaceholderResolver placeholderResolver,
Set<String> visitedPlaceholders) {
StringBuilder buf = new StringBuilder(strVal);
int startIndex = strVal.indexOf(this.placeholderPrefix);
while (startIndex != -1) {
int endIndex = findPlaceholderEndIndex(buf, startIndex);
if (endIndex != -1) {
String placeholder = buf.substring(startIndex + this.placeholderPrefix.length(), endIndex);
if (!visitedPlaceholders.add(placeholder)) {
throw new IllegalArgumentException(
"Circular placeholder reference '" + placeholder + "' in property definitions");
}
// Recursive invocation, parsing placeholders contained in the placeholder key.
placeholder = parseStringValue(placeholder, placeholderResolver, visitedPlaceholders);
// Now obtain the value for the fully resolved key...
int defaultValueIdx = placeholder.indexOf(':');
String defaultValue = null;
if (defaultValueIdx != -1) {
defaultValue = placeholder.substring(defaultValueIdx + 1);
placeholder = placeholder.substring(0, defaultValueIdx);
}
String propVal = placeholderResolver.resolvePlaceholder(placeholder);
if (propVal == null) {
propVal = defaultValue;
}
if (propVal != null) {
// Recursive invocation, parsing placeholders contained in the
// previously resolved placeholder value.
propVal = parseStringValue(propVal, placeholderResolver, visitedPlaceholders);
buf.replace(startIndex, endIndex + this.placeholderSuffix.length(), propVal);
startIndex = buf.indexOf(this.placeholderPrefix, startIndex + propVal.length());
} else if (this.ignoreUnresolvablePlaceholders) {
// Proceed with unprocessed value.
startIndex = buf.indexOf(this.placeholderPrefix, endIndex + this.placeholderSuffix.length());
} else {
throw new IllegalArgumentException("Could not resolve placeholder '" + placeholder + "'");
}
visitedPlaceholders.remove(placeholder);
} else {
startIndex = -1;
}
}
return buf.toString();
}
private int findPlaceholderEndIndex(CharSequence buf, int startIndex) {
int index = startIndex + this.placeholderPrefix.length();
int withinNestedPlaceholder = 0;
while (index < buf.length()) {
if (substringMatch(buf, index, this.placeholderSuffix)) {
if (withinNestedPlaceholder > 0) {
withinNestedPlaceholder--;
index = index + this.placeholderPrefix.length() - 1;
} else {
return index;
}
} else if (substringMatch(buf, index, this.placeholderPrefix)) {
withinNestedPlaceholder++;
index = index + this.placeholderPrefix.length();
} else {
index++;
}
}
return -1;
}
private boolean substringMatch(CharSequence str, int index, CharSequence substring) {
for (int j = 0; j < substring.length(); j++) {
int i = index + j;
if (i >= str.length() || str.charAt(i) != substring.charAt(j)) {
return false;
}
}
return true;
}
}

View file

@ -23,11 +23,9 @@ import java.time.format.DateTimeFormatter;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.HashSet;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.logging.Level;
import java.util.logging.Logger;
@ -687,26 +685,31 @@ public class Settings {
* @return builder
*/
public Builder replacePropertyPlaceholders() {
PropertyPlaceholder propertyPlaceholder = new PropertyPlaceholder("${", "}", false);
PropertyPlaceholder.PlaceholderResolver placeholderResolver = placeholderName -> {
// system property
String value = System.getProperty(placeholderName);
if (value != null) {
return value;
}
// environment
value = System.getenv(placeholderName);
if (value != null) {
return value;
}
// current date
try {
return DateTimeFormatter.ofPattern(placeholderName).format(LocalDate.now());
} catch (IllegalArgumentException | DateTimeException e) {
logger.log(Level.FINER, e.getMessage(), e);
return map.get(placeholderName);
}
};
return replacePropertyPlaceholders(new PropertyPlaceholder("${", "}", false),
placeholderName -> {
// system property
String value = System.getProperty(placeholderName);
if (value != null) {
return value;
}
// environment
value = System.getenv(placeholderName);
if (value != null) {
return value;
}
// current date
try {
return DateTimeFormatter.ofPattern(placeholderName).format(LocalDate.now());
} catch (IllegalArgumentException | DateTimeException e) {
logger.log(Level.FINER, e.getMessage(), e);
return map.get(placeholderName);
}
}
);
}
public Builder replacePropertyPlaceholders(PropertyPlaceholder propertyPlaceholder,
PlaceholderResolver placeholderResolver) {
for (Map.Entry<String, String> entry : map.entrySet()) {
map.put(entry.getKey(), propertyPlaceholder.replacePlaceholders(entry.getValue(), placeholderResolver));
}
@ -717,133 +720,4 @@ public class Settings {
return new Settings(map);
}
}
private static class PropertyPlaceholder {
private final String placeholderPrefix;
private final String placeholderSuffix;
private final boolean ignoreUnresolvablePlaceholders;
/**
* Creates a new <code>PropertyPlaceholderHelper</code> that uses the supplied prefix and suffix.
*
* @param placeholderPrefix the prefix that denotes the start of a placeholder.
* @param placeholderSuffix the suffix that denotes the end of a placeholder.
* @param ignoreUnresolvablePlaceholders indicates whether unresolvable placeholders should be ignored
* (<code>true</code>) or cause an exception (<code>false</code>).
*/
public PropertyPlaceholder(String placeholderPrefix, String placeholderSuffix,
boolean ignoreUnresolvablePlaceholders) {
this.placeholderPrefix = placeholderPrefix;
this.placeholderSuffix = placeholderSuffix;
this.ignoreUnresolvablePlaceholders = ignoreUnresolvablePlaceholders;
}
/**
* Replaces all placeholders of format <code>${name}</code> with the value returned from the supplied {@link
* PlaceholderResolver}.
*
* @param value the value containing the placeholders to be replaced.
* @param placeholderResolver the <code>PlaceholderResolver</code> to use for replacement.
* @return the supplied value with placeholders replaced inline.
*/
public String replacePlaceholders(String value, PlaceholderResolver placeholderResolver) {
return parseStringValue(value, placeholderResolver, new HashSet<String>());
}
protected String parseStringValue(String strVal, PlaceholderResolver placeholderResolver,
Set<String> visitedPlaceholders) {
StringBuilder buf = new StringBuilder(strVal);
int startIndex = strVal.indexOf(this.placeholderPrefix);
while (startIndex != -1) {
int endIndex = findPlaceholderEndIndex(buf, startIndex);
if (endIndex != -1) {
String placeholder = buf.substring(startIndex + this.placeholderPrefix.length(), endIndex);
if (!visitedPlaceholders.add(placeholder)) {
throw new IllegalArgumentException(
"Circular placeholder reference '" + placeholder + "' in property definitions");
}
// Recursive invocation, parsing placeholders contained in the placeholder key.
placeholder = parseStringValue(placeholder, placeholderResolver, visitedPlaceholders);
// Now obtain the value for the fully resolved key...
int defaultValueIdx = placeholder.indexOf(':');
String defaultValue = null;
if (defaultValueIdx != -1) {
defaultValue = placeholder.substring(defaultValueIdx + 1);
placeholder = placeholder.substring(0, defaultValueIdx);
}
String propVal = placeholderResolver.resolvePlaceholder(placeholder);
if (propVal == null) {
propVal = defaultValue;
}
if (propVal != null) {
// Recursive invocation, parsing placeholders contained in the
// previously resolved placeholder value.
propVal = parseStringValue(propVal, placeholderResolver, visitedPlaceholders);
buf.replace(startIndex, endIndex + this.placeholderSuffix.length(), propVal);
startIndex = buf.indexOf(this.placeholderPrefix, startIndex + propVal.length());
} else if (this.ignoreUnresolvablePlaceholders) {
// Proceed with unprocessed value.
startIndex = buf.indexOf(this.placeholderPrefix, endIndex + this.placeholderSuffix.length());
} else {
throw new IllegalArgumentException("Could not resolve placeholder '" + placeholder + "'");
}
visitedPlaceholders.remove(placeholder);
} else {
startIndex = -1;
}
}
return buf.toString();
}
private int findPlaceholderEndIndex(CharSequence buf, int startIndex) {
int index = startIndex + this.placeholderPrefix.length();
int withinNestedPlaceholder = 0;
while (index < buf.length()) {
if (substringMatch(buf, index, this.placeholderSuffix)) {
if (withinNestedPlaceholder > 0) {
withinNestedPlaceholder--;
index = index + this.placeholderPrefix.length() - 1;
} else {
return index;
}
} else if (substringMatch(buf, index, this.placeholderPrefix)) {
withinNestedPlaceholder++;
index = index + this.placeholderPrefix.length();
} else {
index++;
}
}
return -1;
}
private boolean substringMatch(CharSequence str, int index, CharSequence substring) {
for (int j = 0; j < substring.length(); j++) {
int i = index + j;
if (i >= str.length() || str.charAt(i) != substring.charAt(j)) {
return false;
}
}
return true;
}
/**
* Strategy interface used to resolve replacement values for placeholders contained in Strings.
*/
@FunctionalInterface
public interface PlaceholderResolver {
/**
* Resolves the supplied placeholder name into the replacement value.
*
* @param placeholderName the name of the placeholder to resolve.
* @return the replacement value or <code>null</code> if no replacement is to be made.
*/
String resolvePlaceholder(String placeholderName);
}
}
}