add ElementRemover

json-smart/src/main/java/net/minidev/json/actions/ElementRemover.java

@@ -0,0 +1,51 @@
+package net.minidev.json.actions;
+
+import net.minidev.json.JSONArray;
+import net.minidev.json.JSONObject;
+import net.minidev.json.actions.traverse.JSONTraverser;
+import net.minidev.json.actions.traverse.RemoveElementsAction;
+import net.minidev.json.actions.traverse.TraverseAction;
+
+import java.util.*;
+
+/**
+ * <b>Removes key:value elements from every node of a {@link JSONObject} matching the list of user-specified elements.</b>
+ * <p>
+ * An element to remove must be specified as a key:value pair
+ * <p>
+ * <b>Usage Example:</b>
+ * <p>
+ * To remove the element k2:v2 from the {@link JSONObject} {k0:{k2:v2, k3:v3}, k1:{k2:v2, k4:v4}} use the remover like so:
+ * <pre>
+ * PathRemover pr = new PathRemover("k2.v2");
+ * JSONObject cleanObject = pr.remove(new JSONObject(...));
+ * </pre>
+ * The resulting object 'cleanObject' would be {k0:{k3:v3}, k1:{k4:v4}}
+ * <p>
+ * See unit tests for more examples
+ *
+ * @author adoneitan@gmail.com
+ *
+ */
+public class ElementRemover
+{
+private Map<String, Object> elementsToRemove;
+
+public ElementRemover(Map<String, Object> elementsToRemove)
+{
+this.elementsToRemove = elementsToRemove == null ? Collections.<String, Object>emptyMap() : elementsToRemove;
+}
+
+public ElementRemover(JSONObject elementsToRemove)
+{
+this.elementsToRemove = elementsToRemove == null ? Collections.<String, Object>emptyMap() : elementsToRemove;
+}
+
+public JSONObject remove(JSONObject objectToClean)
+{
+TraverseAction strategy = new RemoveElementsAction(this.elementsToRemove);
+JSONTraverser traversal = new JSONTraverser(strategy);
+traversal.traverse(objectToClean);
+return (JSONObject) strategy.result();
+}
+}

json-smart/src/main/java/net/minidev/json/actions/traverse/RemoveElementsAction.java

@@ -0,0 +1,87 @@
+package net.minidev.json.actions.traverse;
+
+import net.minidev.json.JSONObject;
+
+import java.util.Iterator;
+import java.util.List;
+import java.util.Map;
+
+/**
+ * <b>Removes key:value elements from a {@link JSONObject}.</b>
+ * <p>
+ * An element is not removed from the user-specified list once its processing is over,
+ * because it may appear in more than one node.
+ * <p>
+ * See package-info for more details
+ * <p>
+ * See unit tests for examples
+ *
+ * @author adoneitan@gmail.com
+ *
+ */
+public class RemoveElementsAction implements TraverseAction
+{
+protected JSONObject result;
+protected final Map<String, Object> elementsToRemove;
+protected final boolean allowDotChar;
+
+public RemoveElementsAction(Map<String, Object> elementsToRemove, boolean allowDotChar)
+{
+this.elementsToRemove = elementsToRemove;
+this.allowDotChar = allowDotChar;
+}
+
+public RemoveElementsAction(Map<String, Object> elementsToRemove)
+{
+this(elementsToRemove, false);
+}
+
+@Override
+public boolean handleStart(JSONObject object)
+{
+result = object;
+return object != null && elementsToRemove != null && elementsToRemove.size() > 0;
+}
+
+@Override
+public boolean handleDotChar() {
+return allowDotChar;
+}
+
+@Override
+public boolean handleEntryAndIgnoreChildren(String pathToEntry, Iterator<Map.Entry<String, Object>> it, Map.Entry<String, Object> entry)
+{
+if (elementsToRemove.entrySet().contains(entry))
+{
+it.remove();
+}
+return false;
+}
+
+@Override
+public boolean handleNext()
+{
+//must traverse the whole object
+return true;
+}
+
+@Override
+public boolean handleJSONObjectChild() {
+return true;
+}
+
+@Override
+public boolean handleJSONArrayChild() {
+return true;
+}
+
+@Override
+public void handleEnd() {
+//nothing to do
+}
+
+@Override
+public Object result() {
+return result;
+}
+}

json-smart/src/test/java/net/minidev/json/test/actions/ElementRemoverTest.java

@@ -0,0 +1,106 @@
+package net.minidev.json.test.actions;
+
+import net.minidev.json.JSONArray;
+import net.minidev.json.JSONObject;
+import net.minidev.json.JSONValue;
+import net.minidev.json.actions.ElementRemover;
+import net.minidev.json.parser.ParseException;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.Parameterized;
+
+import java.util.*;
+
+import static org.junit.Assert.assertEquals;
+
+/**
+ * Tests {@link ElementRemover}
+ *
+ * @author adoneitan@gmail.com
+ */
+@RunWith(Parameterized.class)
+public class ElementRemoverTest
+{
+private String jsonToClean;
+private String elementsToRemove;
+private String expectedJson;
+
+public ElementRemoverTest(String jsonToClean, String elementsToRemove, String expectedJson)
+{
+this.jsonToClean = jsonToClean;
+this.elementsToRemove = elementsToRemove;
+this.expectedJson = expectedJson;
+}
+
+@Parameterized.Parameters
+public static Collection params()
+{
+return Arrays.asList(new Object[][]{
+
+{"{\"k0\":{\"k2\":\"v2\"},\"k1\":{\"k2\":\"v2\",\"k3\":\"v3\"}}", null, "{\"k0\":{\"k2\":\"v2\"},\"k1\":{\"k2\":\"v2\",\"k3\":\"v3\"}}"},
+{"{\"k0\":{\"k2\":\"v2\"},\"k1\":{\"k2\":\"v2\",\"k3\":\"v3\"}}", "{}", "{\"k0\":{\"k2\":\"v2\"},\"k1\":{\"k2\":\"v2\",\"k3\":\"v3\"}}"},
+{"{\"k0\":{\"k2\":\"v2\"},\"k1\":{\"k2\":\"v2\",\"k3\":\"v3\"}}", "{\"k0\":\"v2\"}", "{\"k0\":{\"k2\":\"v2\"},\"k1\":{\"k2\":\"v2\",\"k3\":\"v3\"}}"},
+{"{\"k0\":{\"k2\":\"v2\"},\"k1\":{\"k2\":\"v2\",\"k3\":\"v3\"}}", "{\"k2\":\"v2\"}", "{\"k0\":{},\"k1\":{\"k3\":\"v3\"}}"},
+{"{\"k0\":{\"k2\":\"v2\"},\"k1\":{\"k2\":\"v2\",\"k3\":\"v3\"}}", "{\"k0\":{\"k2\":\"v2\"}}", "{\"k1\":{\"k2\":\"v2\",\"k3\":\"v3\"}}"},
+{"{\"k0\":{\"k2\":\"v2\"},\"k1\":{\"k2\":\"v2\",\"k3\":\"v3\"}}", "{\"k2\":\"v2\",\"k3\":\"v3\"}", "{\"k0\":{},\"k1\":{}}"},
+{"{\"k0\":{}}", "{}", "{\"k0\":{}}"},
+});
+}
+
+@Test
+public void test() throws ParseException
+{
+JSONObject objectToClean = jsonToClean != null ? (JSONObject) JSONValue.parseWithException(jsonToClean) : null;
+JSONObject expectedObject = expectedJson != null ? (JSONObject) JSONValue.parseWithException(expectedJson): null;
+JSONObject toRemove = elementsToRemove != null ? (JSONObject) JSONValue.parseWithException(elementsToRemove): null;
+ElementRemover er = new ElementRemover(toRemove);
+er.remove(objectToClean);
+assertEquals(expectedObject, objectToClean);
+}
+
+//	private ElementRemover switchKeyToRemove()
+//	{
+//	long m = System.currentTimeMillis();
+//	if (elementsToRemove == null && m % 4 == 0)
+//	{
+//	System.out.println("cast to String");
+//	return new ElementRemover((String)null);
+//	}
+//	else if (elementsToRemove == null && m % 4 == 1)
+//	{
+//	System.out.println("cast to String[]");
+//	return new ElementRemover((String[])null);
+//	}
+//	else if (elementsToRemove == null && m % 4 == 2)
+//	{
+//	System.out.println("cast to JSONArray");
+//	return new ElementRemover((JSONArray)null);
+//	}
+//	else if (elementsToRemove == null && m % 4 == 3)
+//	{
+//	System.out.println("cast to List<String>");
+//	return new ElementRemover((List<String>)null);
+//	}
+//	else if (elementsToRemove instanceof String)
+//	{
+//	return new ElementRemover((String) elementsToRemove);
+//	}
+//	else if (elementsToRemove instanceof String[])
+//	{
+//	return new ElementRemover((String[]) elementsToRemove);
+//	}
+//	else if (elementsToRemove instanceof JSONArray)
+//	{
+//	return new ElementRemover((JSONArray) elementsToRemove);
+//	}
+//	else if (elementsToRemove instanceof List<?>)
+//	{
+//	return new ElementRemover((List<String>) elementsToRemove);
+//	}
+//	else
+//	{
+//	throw new IllegalArgumentException("bad test setup: wrong type of key to remove");
+//	}
+//	}
+
+}