Merge 3631be9 into 19564dc

pom.xml

@@ -369,6 +369,12 @@
             <version>2.2</version>
             <scope>test</scope>
         </dependency>
+        <dependency>
+            <groupId>org.codehaus.jackson</groupId>
+            <artifactId>jackson-mapper-asl</artifactId>
+            <version>1.9.13</version>
+            <scope>compile</scope>
+        </dependency>
     </dependencies>
 
     <reporting>

src/main/java/de/danielbechler/diff/node/DiffJSONVisitor.java

@@ -0,0 +1,72 @@
+package de.danielbechler.diff.node;
+
+import de.danielbechler.diff.path.NodePath;
+import de.danielbechler.diff.selector.BeanPropertyElementSelector;
+import de.danielbechler.diff.selector.ElementSelector;
+import de.danielbechler.util.Strings;
+import org.codehaus.jackson.map.ObjectMapper;
+
+import java.io.IOException;
+import java.util.LinkedHashMap;
+import java.util.List;
+import java.util.Map;
+
+/**
+ * This visitor can take the differencies and output the value from the modified object.
+ * You can either get the result as a {@link Map} or get it as a JSON-string.
+ * @author Patrick Fust (patrickfust)
+ */
+public class DiffJSONVisitor extends PrintingVisitor {
+
+    private final Map<String, Object> messages = new LinkedHashMap<String, Object>();
+
+    public DiffJSONVisitor(Object working, Object base) {
+        super(working, base);
+    }
+
+    @Override
+    protected String differenceToString(DiffNode node, Object base, Object modified) {
+        String text = Strings.toSingleLineString(node.canonicalGet(modified));
+        NodePath nodePath = node.getPath();
+        getMapFromPath(nodePath).put(getLastName(nodePath), text);
+        return text;
+    }
+
+    public Map<String, Object> getMessagesAsMap() {
+        return messages;
+    }
+
+    public String getAsJSON() throws IOException {
+        return new ObjectMapper().writeValueAsString(messages);
+    }
+
+    @Override
+    protected void print(final String text) {
+    }
+
+    private Map<String, Object> getMapFromPath(NodePath path) {
+        Map<String, Object> resultMap = messages;
+        List<ElementSelector> elementSelectors = path.getElementSelectors();
+        int idx = 0;
+        for (ElementSelector elementSelector : elementSelectors) {
+            if (elementSelector instanceof BeanPropertyElementSelector) {
+                BeanPropertyElementSelector beanPropertyElementSelector = (BeanPropertyElementSelector) elementSelector;
+                if (idx != elementSelectors.size() - 1) { // Has more -> go deeper
+                    String key = beanPropertyElementSelector.getPropertyName();
+                    Map<String, Object> resultMapTmp = (Map<String, Object>) resultMap.get(key);
+                    if (resultMapTmp == null) {
+                        resultMapTmp = new LinkedHashMap<String, Object>();
+                        resultMap.put(key, resultMapTmp);
+                        resultMap = resultMapTmp;
+                    }
+                }
+            }
+            idx++;
+        }
+        return resultMap;
+    }
+
+    private String getLastName(NodePath path) {
+        return ((BeanPropertyElementSelector) path.getLastElementSelector()).getPropertyName();
+    }
+}

src/test/java/de/danielbechler/diff/node/DiffJSONVisitorTest.groovy

@@ -0,0 +1,57 @@
+package de.danielbechler.diff.node
+
+import de.danielbechler.diff.ObjectDifferBuilder
+import spock.lang.Specification
+
+
+class DiffJSONVisitorTest extends Specification {
+
+    DiffJSONVisitor visitor
+
+    Something workingObject
+    Something baseObject
+
+    def setup() {
+        workingObject = new Something(name: 'working name', someOther: new Something(name: 'working other'), theSame: 'theSame')
+        baseObject = new Something(name: 'base name', someOther: new Something(name: 'base other'), theSame: 'theSame')
+        visitor = new DiffJSONVisitor(workingObject, baseObject)
+    }
+
+    def "something to map"() {
+        when:
+        DiffNode root = ObjectDifferBuilder.buildDefault().compare(workingObject, baseObject)
+        root.visit(visitor)
+        Map<String, Object> messages = visitor.messagesAsMap
+
+        then:
+        messages.name == 'working name'
+        messages.someOther.name == 'working other'
+    }
+
+    def "something to json"() {
+        when:
+        DiffNode root = ObjectDifferBuilder.buildDefault().compare(workingObject, baseObject)
+        root.visit(visitor)
+        String json = visitor.getAsJSON()
+
+        then:
+        json == '{"name":"working name","someOther":{"name":"working other"}}'
+    }
+
+    def "clearing a field"() {
+        when:
+        workingObject.name = null
+        DiffNode root = ObjectDifferBuilder.buildDefault().compare(workingObject, baseObject)
+        root.visit(visitor)
+        String json = visitor.getAsJSON()
+
+        then:
+        json == '{"name":null,"someOther":{"name":"working other"}}'
+    }
+
+    static class Something {
+        String name
+        String theSame
+        Something someOther
+    }
+}