fix JSON construction with maps/collections, more convenience for converting strings

datastructures-api/src/main/java/org/xbib/datastructures/api/Builder.java

@@ -16,7 +16,7 @@ public interface Builder {
 
     Builder buildMap(Map<String, Object> map) throws IOException;
 
-    Builder buildCollection(Collection<Object> collection) throws IOException;
+    Builder buildCollection(Collection<?> collection) throws IOException;
 
     Builder buildKey(CharSequence key) throws IOException;
 
@@ -24,7 +24,13 @@ public interface Builder {
 
     Builder buildNull() throws IOException;
 
-    default Builder buildIfNotNull(CharSequence key, Object value) throws IOException {
+    default Builder field(CharSequence key, Object value) throws IOException {
+        buildKey(key);
+        buildValue(value);
+        return this;
+    }
+
+    default Builder fieldIfNotNull(CharSequence key, Object value) throws IOException {
         if (value != null){
             buildKey(key);
             buildValue(value);
@@ -32,5 +38,25 @@ public interface Builder {
         return this;
     }
 
+    default Builder collection(CharSequence key, Collection<?> value) throws IOException {
+        buildKey(key);
+        buildValue(value);
+        return this;
+    }
+
+    default Builder beginMap(CharSequence key) throws IOException {
+        buildKey(key);
+        beginMap();
+        return this;
+    }
+
+    default Builder beginCollection(CharSequence key) throws IOException {
+        buildKey(key);
+        beginCollection();
+        return this;
+    }
+
+    Builder copy(Builder builder) throws IOException;
+
     String build();
 }

datastructures-json-tiny/src/main/java/org/xbib/datastructures/json/tiny/Json.java

@@ -1,13 +1,23 @@
 package org.xbib.datastructures.json.tiny;
 
-import org.xbib.datastructures.api.*;
+import org.xbib.datastructures.api.Builder;
-
+import org.xbib.datastructures.api.ByteSizeValue;
+import org.xbib.datastructures.api.DataStructure;
+import org.xbib.datastructures.api.Generator;
+import org.xbib.datastructures.api.Node;
+import org.xbib.datastructures.api.Parser;
+import org.xbib.datastructures.api.TimeValue;
+import java.io.IOException;
+import java.io.StringReader;
 import java.io.StringWriter;
 import java.time.Instant;
+import java.util.Map;
 import java.util.function.Consumer;
 
 public class Json implements DataStructure {
 
+    private static final Json INSTANCE = new Json();
+
     private final char separator;
 
     private Node<?> root;
@@ -25,6 +35,15 @@ public class Json implements DataStructure {
         this.separator = separator;
     }
 
+    @SuppressWarnings("unchecked")
+    public static Map<String, Object> toMap(String yaml) throws IOException {
+        return (Map<String, Object>) INSTANCE.createParser().parse(new StringReader(yaml)).get();
+    }
+
+    public static String toString(Map<String, Object> map) throws IOException {
+        return INSTANCE.createBuilder().buildMap(map).build();
+    }
+
     @Override
     public Parser createParser() {
         return new StreamParser();

datastructures-json-tiny/src/main/java/org/xbib/datastructures/json/tiny/JsonBuilder.java

@@ -3,11 +3,8 @@ package org.xbib.datastructures.json.tiny;
 import org.xbib.datastructures.api.Builder;
 import org.xbib.datastructures.api.ByteSizeValue;
 import org.xbib.datastructures.api.TimeValue;
-
 import java.io.IOException;
-import java.io.StringWriter;
 import java.io.UncheckedIOException;
-import java.io.Writer;
 import java.time.Instant;
 import java.util.Collection;
 import java.util.Map;
@@ -15,31 +12,31 @@ import java.util.Objects;
 
 public class JsonBuilder implements Builder {
 
-    private final Writer writer;
+    private final Appendable appendable;
 
     private State state;
 
     public JsonBuilder() {
-        this(new StringWriter());
+        this(new StringBuilder());
     }
 
-    public JsonBuilder(Writer writer) {
+    public JsonBuilder(Appendable appendable) {
-        this.writer = writer;
+        this.appendable = appendable;
-        this.state = new State(null, 0, Structure.MAP, true);
+        this.state = new State(null, 0, Structure.DOCSTART, true);
     }
 
     public static JsonBuilder builder() {
         return new JsonBuilder();
     }
 
-    public static JsonBuilder builder(Writer writer) {
+    public static JsonBuilder builder(Appendable appendable) {
-        return new JsonBuilder(writer);
+        return new JsonBuilder(appendable);
     }
 
     @Override
     public Builder beginCollection() throws IOException {
         this.state = new State(state, state.level + 1, Structure.COLLECTION, true);
-        writer.write('[');
+        appendable.append('[');
         return this;
     }
 
@@ -48,7 +45,7 @@ public class JsonBuilder implements Builder {
         if (state.structure != Structure.COLLECTION) {
             throw new JsonException("no array to close");
         }
-        writer.write(']');
+        appendable.append(']');
         this.state = state != null ? state.parent : null;
         return this;
     }
@@ -56,25 +53,30 @@ public class JsonBuilder implements Builder {
     @Override
     public Builder beginMap() throws IOException {
         this.state = new State(state, state.level + 1, Structure.MAP, true);
-        writer.write('{');
+        appendable.append('{');
         return this;
     }
 
     @Override
     public Builder endMap() throws IOException {
-        if (state.structure != Structure.MAP) {
+        if (state.structure != Structure.MAP && state.structure != Structure.KEY) {
             throw new JsonException("no object to close");
         }
-        writer.write('}');
+        appendable.append('}');
         this.state = state != null ? state.parent : null;
         return this;
     }
 
-
     @Override
     public Builder buildMap(Map<String, Object> map) throws IOException {
         Objects.requireNonNull(map);
-        beginMap();
+        if (state.structure == Structure.COLLECTION) {
+            beginArrayValue(map);
+        }
+        boolean wrap = state.structure != Structure.MAP;
+        if (wrap) {
+            beginMap();
+        }
         map.forEach((k, v) -> {
             try {
                 buildKey(k);
@@ -83,12 +85,17 @@ public class JsonBuilder implements Builder {
                 throw new UncheckedIOException(e);
             }
         });
-        endMap();
+        if (wrap) {
+            endMap();
+        }
+        if (state.structure == Structure.COLLECTION) {
+            endArrayValue(map);
+        }
         return this;
     }
 
     @Override
-    public Builder buildCollection(Collection<Object> collection) throws IOException {
+    public Builder buildCollection(Collection<?> collection) throws IOException {
         Objects.requireNonNull(collection);
         beginCollection();
         collection.forEach(v -> {
@@ -105,7 +112,7 @@ public class JsonBuilder implements Builder {
     @SuppressWarnings("unchecked")
     @Override
     public Builder buildValue(Object object) throws IOException {
-        if (state.structure == Structure.MAP) {
+        if (state.structure == Structure.MAP || state.structure == Structure.KEY) {
             beginValue(object);
         } else if (state.structure == Structure.COLLECTION) {
             beginArrayValue(object);
@@ -142,7 +149,7 @@ public class JsonBuilder implements Builder {
         } else {
             throw new IllegalArgumentException("unable to write object class " + object.getClass());
         }
-        if (state.structure == Structure.MAP) {
+        if (state.structure == Structure.MAP || state.structure == Structure.KEY) {
             endValue(object);
         } else if (state.structure == Structure.COLLECTION) {
             endArrayValue(object);
@@ -152,42 +159,68 @@ public class JsonBuilder implements Builder {
 
     @Override
     public Builder buildKey(CharSequence string) throws IOException {
-        if (state.structure == Structure.MAP) {
+        if (state.structure == Structure.COLLECTION) {
+            beginArrayValue(string);
+        }
+        if (state.structure == Structure.MAP || state.structure == Structure.KEY) {
             beginKey(string != null ? string.toString() : null);
         }
         buildString(string, true);
-        if (state.structure == Structure.MAP) {
+        if (state.structure == Structure.MAP || state.structure == Structure.KEY) {
             endKey(string != null ? string.toString() : null);
         }
+        state.structure = Structure.KEY;
         return this;
     }
 
     @Override
     public Builder buildNull() throws IOException {
-        if (state.structure == Structure.MAP) {
+        if (state.structure == Structure.MAP || state.structure == Structure.KEY) {
             beginValue(null);
         } else if (state.structure == Structure.COLLECTION) {
             beginArrayValue(null);
         }
         buildString("null", false);
+        if (state.structure == Structure.MAP || state.structure == Structure.KEY) {
+            endValue(null);
+        } else if (state.structure == Structure.COLLECTION) {
+            endArrayValue(null);
+        }
+        return this;
+    }
+
+    @Override
+    public Builder copy(Builder builder) throws IOException {
+        if (state.structure == Structure.MAP || state.structure == Structure.KEY) {
+            beginValue(null);
+        } else if (state.structure == Structure.COLLECTION) {
+            beginArrayValue(null);
+        }
+        appendable.append(builder.build());
+        if (state.structure == Structure.MAP || state.structure == Structure.KEY) {
+            endValue(null);
+        }
+        if (state.structure == Structure.COLLECTION) {
+            endArrayValue(null);
+        }
         return this;
     }
 
     @Override
     public String build() {
-        return writer.toString();
+        return appendable.toString();
     }
 
     private void beginKey(String k) throws IOException {
         if (state.first) {
             state.first = false;
         } else {
-            writer.write(",");
+            appendable.append(",");
         }
     }
 
     private void endKey(String k) throws IOException {
-        writer.write(":");
+        appendable.append(":");
     }
 
     private void beginValue(Object v) {
@@ -200,7 +233,7 @@ public class JsonBuilder implements Builder {
         if (state.first) {
             state.first = false;
         } else {
-            writer.write(",");
+            appendable.append(",");
         }
     }
 
@@ -220,10 +253,10 @@ public class JsonBuilder implements Builder {
     }
 
     private void buildString(CharSequence string, boolean escape) throws IOException {
-        writer.write(escape ? escapeString(string) : string.toString());
+        appendable.append(escape ? escapeString(string) : string);
     }
 
-    private String escapeString(CharSequence string) {
+    private CharSequence escapeString(CharSequence string) {
         StringBuilder sb = new StringBuilder();
         sb.append('"');
         int start = 0;
@@ -232,17 +265,17 @@ public class JsonBuilder implements Builder {
             char c = string.charAt(i);
             if (c == '"' || c < 32 || c >= 127 || c == '\\') {
                 if (start < i) {
-                    sb.append(string.toString(), start, i - start);
+                    sb.append(string, start, i - start);
                 }
                 start = i;
                 sb.append(escapeCharacter(c));
             }
         }
         if (start < l) {
-            sb.append(string.toString(), start, l - start);
+            sb.append(string, start, l - start);
         }
         sb.append('"');
-        return sb.toString();
+        return sb;
     }
 
     private static String escapeCharacter(char c) {
@@ -264,7 +297,7 @@ public class JsonBuilder implements Builder {
         return "\\u0000".substring(0, 6 - hex.length()) + hex;
     }
 
-    private enum Structure { MAP, COLLECTION };
+    private enum Structure { DOCSTART, MAP, KEY, COLLECTION };
 
     private static class State {
         State parent;

datastructures-json-tiny/src/test/java/org/xbib/datastructures/json/tiny/test/JsonBuilderTest.java

@@ -6,6 +6,7 @@ import org.xbib.datastructures.json.tiny.StreamParser;
 
 import java.io.IOException;
 import java.io.StringReader;
+import java.util.Arrays;
 import java.util.List;
 import java.util.Map;
 
@@ -108,4 +109,108 @@ public class JsonBuilderTest {
         jsonBuilder.buildMap(Map.of("a", "b"));
         assertEquals("{\"a\":\"b\"}", jsonBuilder.build());
     }
+
+    @Test
+    public void testKeyValue() throws Exception {
+        JsonBuilder jsonBuilder = new JsonBuilder();
+        jsonBuilder.beginMap();
+        jsonBuilder.buildKey("a");
+        jsonBuilder.buildValue("b");
+        // test comma separation
+        jsonBuilder.buildKey("c");
+        jsonBuilder.buildValue("d");
+        jsonBuilder.endMap();
+        assertEquals("{\"a\":\"b\",\"c\":\"d\"}", jsonBuilder.build());
+    }
+
+    @Test
+    public void testMapBuild() throws Exception {
+        JsonBuilder jsonBuilder = new JsonBuilder();
+        jsonBuilder.beginMap();
+        jsonBuilder.buildKey("map");
+        // buildMap is wrapped with '{' and '}'
+        jsonBuilder.buildMap(Map.of("a", "b"));
+        jsonBuilder.endMap();
+        assertEquals("{\"map\":{\"a\":\"b\"}}", jsonBuilder.build());
+    }
+
+    @Test
+    public void testBeginMapBuild() throws Exception {
+        JsonBuilder jsonBuilder = new JsonBuilder();
+        jsonBuilder.beginMap();
+        jsonBuilder.beginMap("map");
+        // buildMap is not wrapped with '{' and '}'
+        jsonBuilder.buildMap(Map.of("a", "b"));
+        jsonBuilder.endMap();
+        jsonBuilder.endMap();
+        assertEquals("{\"map\":{\"a\":\"b\"}}", jsonBuilder.build());
+    }
+
+    @Test
+    public void testMapOfCollections() throws Exception {
+        JsonBuilder jsonBuilder = new JsonBuilder();
+        jsonBuilder.beginMap();
+        jsonBuilder.beginMap("map");
+        jsonBuilder.collection("a", Arrays.asList("b", "c"));
+        // test comma separation
+        jsonBuilder.collection("d", Arrays.asList("e", "f"));
+        jsonBuilder.endMap();
+        jsonBuilder.endMap();
+        assertEquals("{\"map\":{\"a\":[\"b\",\"c\"],\"d\":[\"e\",\"f\"]}}", jsonBuilder.build());
+    }
+
+    @Test
+    public void testMapOfEmptyCollections() throws Exception {
+        JsonBuilder jsonBuilder = new JsonBuilder();
+        jsonBuilder.beginMap();
+        jsonBuilder.beginMap("map");
+        jsonBuilder.collection("a", List.of());
+        // test comma separation
+        jsonBuilder.collection("b", List.of());
+        jsonBuilder.endMap();
+        jsonBuilder.endMap();
+        assertEquals("{\"map\":{\"a\":[],\"b\":[]}}", jsonBuilder.build());
+    }
+
+    @Test
+    public void testCollectionOfMaps() throws Exception {
+        JsonBuilder jsonBuilder = new JsonBuilder();
+        jsonBuilder.beginMap();
+        jsonBuilder.beginCollection("collection");
+        jsonBuilder.buildMap(Map.of("a", "b"));
+        // test comma separation
+        jsonBuilder.buildMap(Map.of("c", "d"));
+        jsonBuilder.endCollection();
+        jsonBuilder.endMap();
+        assertEquals("{\"collection\":[{\"a\":\"b\"},{\"c\":\"d\"}]}", jsonBuilder.build());
+    }
+
+    @Test
+    public void testCollectionOfEmptyMaps() throws Exception {
+        JsonBuilder jsonBuilder = new JsonBuilder();
+        jsonBuilder.beginMap();
+        jsonBuilder.beginCollection("collection");
+        jsonBuilder.buildMap(Map.of());
+        // test comma separation
+        jsonBuilder.buildMap(Map.of());
+        jsonBuilder.endCollection();
+        jsonBuilder.endMap();
+        assertEquals("{\"collection\":[{},{}]}", jsonBuilder.build());
+    }
+
+    @Test
+    public void testCopy() throws Exception {
+        JsonBuilder jsonBuilder1 = new JsonBuilder();
+        jsonBuilder1.buildMap(Map.of("a", "b"));
+        JsonBuilder jsonBuilder2 = new JsonBuilder();
+        jsonBuilder2.buildMap(Map.of("c", "d"));
+        JsonBuilder jsonBuilder = new JsonBuilder();
+        jsonBuilder.beginCollection();
+        jsonBuilder.copy(jsonBuilder1);
+        // test comma separation
+        jsonBuilder.copy(jsonBuilder2);
+        jsonBuilder.endCollection();
+        assertEquals("[{\"a\":\"b\"},{\"c\":\"d\"}]", jsonBuilder.build());
+    }
+
 }

datastructures-yaml-tiny/src/main/java/org/xbib/datastructures/yaml/tiny/Yaml.java

@@ -3,12 +3,17 @@ package org.xbib.datastructures.yaml.tiny;
 import org.xbib.datastructures.api.*;
 import org.xbib.datastructures.api.Builder;
 
+import java.io.IOException;
+import java.io.StringReader;
 import java.io.StringWriter;
 import java.time.Instant;
+import java.util.Map;
 import java.util.function.Consumer;
 
 public class Yaml implements DataStructure {
 
+    private static final Yaml INSTANCE = new Yaml();
+;
     private final char separator;
 
     private Node<?> root;
@@ -26,6 +31,15 @@ public class Yaml implements DataStructure {
         this.separator = separator;
     }
 
+    @SuppressWarnings("unchecked")
+    public static Map<String, Object> toMap(String yaml) throws IOException {
+        return (Map<String, Object>) INSTANCE.createParser().parse(new StringReader(yaml)).get();
+    }
+
+    public static String toString(Map<String, Object> map) throws IOException {
+        return INSTANCE.createBuilder().buildMap(map).build();
+    }
+
     @Override
     public Parser createParser() {
         return new YamlParser();

datastructures-yaml-tiny/src/main/java/org/xbib/datastructures/yaml/tiny/YamlBuilder.java

@@ -4,9 +4,7 @@ import org.xbib.datastructures.api.Builder;
 import org.xbib.datastructures.api.ByteSizeValue;
 import org.xbib.datastructures.api.TimeValue;
 import java.io.IOException;
-import java.io.StringWriter;
 import java.io.UncheckedIOException;
-import java.io.Writer;
 import java.time.Instant;
 import java.util.Collection;
 import java.util.Map;
@@ -14,22 +12,22 @@ import java.util.Objects;
 
 public class YamlBuilder implements Builder {
 
-    public final Writer writer;
+    public final Appendable appendable;
 
     private final int indent;
 
     private State state;
 
     public YamlBuilder() {
-        this(new StringWriter());
+        this(new StringBuilder());
     }
 
-    public YamlBuilder(Writer writer) {
+    public YamlBuilder(Appendable appendable) {
-        this(writer, 2);
+        this(appendable, 2);
     }
 
-    public YamlBuilder(Writer writer, int indent) {
+    public YamlBuilder(Appendable appendable, int indent) {
-        this.writer = writer;
+        this.appendable = appendable;
         this.indent = indent;
         this.state = new State(null, 0, Structure.MAP, false);
     }
@@ -38,8 +36,8 @@ public class YamlBuilder implements Builder {
         return new YamlBuilder();
     }
 
-    public static YamlBuilder builder(Writer writer) {
+    public static YamlBuilder builder(Appendable appendable) {
-        return new YamlBuilder(writer);
+        return new YamlBuilder(appendable);
     }
 
     @Override
@@ -89,7 +87,7 @@ public class YamlBuilder implements Builder {
     }
 
     @Override
-    public Builder buildCollection(Collection<Object> collection) {
+    public Builder buildCollection(Collection<?> collection) {
         Objects.requireNonNull(collection);
         beginCollection();
         collection.forEach(v -> {
@@ -170,9 +168,16 @@ public class YamlBuilder implements Builder {
         return this;
     }
 
+    @Override
+    public Builder copy(Builder builder) throws IOException {
+        // TODO: no correct indent yet for copied yaml
+        buildValue(builder.build());
+        return this;
+    }
+
     @Override
     public String build() {
-        return writer.toString();
+        return appendable.toString();
     }
 
     private void buildNumber(Number number) throws IOException {
@@ -188,7 +193,8 @@ public class YamlBuilder implements Builder {
     }
 
     private void buildString(CharSequence string, boolean escape) throws IOException {
-        String value = escape ? escapeString(string) : string.toString();
+        CharSequence charSequence = escape ? escapeString(string) : string;
+        String value = charSequence.toString();
         if (!((value.startsWith("'") && value.endsWith("'")) || (value.startsWith("\"") && value.endsWith("\""))) &&
                 value.matches(".*[?\\-#:>|$%&{}\\[\\]]+.*|[ ]+")) {
             if (value.contains("\"")) {
@@ -197,7 +203,7 @@ public class YamlBuilder implements Builder {
                 value = "\"" + value + "\"";
             }
         }
-        writer.write(value);
+        appendable.append(value);
     }
 
     private void beginKey(String k) throws IOException {
@@ -205,11 +211,11 @@ public class YamlBuilder implements Builder {
             state.parent.item = false;
             return;
         }
-        writer.write(" ".repeat((state.level - 1) * indent));
+        appendable.append(" ".repeat((state.level - 1) * indent));
     }
 
     private void endKey(String k) throws IOException {
-        writer.write(": ");
+        appendable.append(": ");
     }
 
     private void beginValue(Object v) throws IOException {
@@ -236,8 +242,8 @@ public class YamlBuilder implements Builder {
         if (v instanceof Collection) {
             return;
         }
-        writer.write(" ".repeat((state.level - 1) * indent));
+        appendable.append(" ".repeat((state.level - 1) * indent));
-        writer.write("- ");
+        appendable.append("- ");
         state.item = true;
     }
 
@@ -252,10 +258,10 @@ public class YamlBuilder implements Builder {
     }
 
     private void writeLn() throws IOException{
-        writer.write(System.lineSeparator());
+        appendable.append(System.lineSeparator());
     }
 
-    private String escapeString(CharSequence string) {
+    private CharSequence escapeString(CharSequence string) {
         StringBuilder sb = new StringBuilder();
         int start = 0;
         int l = string.length();
@@ -263,16 +269,16 @@ public class YamlBuilder implements Builder {
             char c = string.charAt(i);
             if (c == '"' || c < 32 || c >= 127 || c == '\\') {
                 if (start < i) {
-                    sb.append(string.toString(), start, i - start);
+                    sb.append(string, start, i - start);
                 }
                 start = i;
                 sb.append(escapeCharacter(c));
             }
         }
         if (start < l) {
-            sb.append(string.toString(), start, l - start);
+            sb.append(string, start, l - start);
         }
-        return sb.toString();
+        return sb;
     }
 
     private static String escapeCharacter(char c) {