Johannes/gson-comments
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

Added code to ensure that circular reference situations with custom handlers are detected.

Browse Source 
Split CircularReferenceTest out of ObjectTest.
This commit is contained in:
Inderjeet Singh 2009-09-29 20:43:31 +00:00
parent 933a3e5150
commit 907082102d
5 changed files with 236 additions and 77 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

46
gson/src/main/java/com/google/gson/CircularReferenceException.java Normal file
View File

@ -0,0 +1,46 @@
/*
* Copyright (C) 2009 Google Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.google.gson;
import java.lang.reflect.Field;
/**
* Exception class to indicate a circular reference error.
* This class is not part of the public API and hence is not public.
*
* @author Inderjeet Singh
* @author Joel Leitch
*/
final class CircularReferenceException extends RuntimeException {
private static final long serialVersionUID = 7444343294106513081L;
private final Object offendingNode;
CircularReferenceException(Object offendingNode) {
super("circular reference error");
this.offendingNode = offendingNode;
}
public IllegalStateException createDetailedException(Field offendingField) {
StringBuilder msg = new StringBuilder(getMessage());
if (offendingField != null) {
msg.append("\n ").append("Offending field: ").append(offendingField.getName() + "\n");
}
if (offendingNode != null) {
msg.append("\n ").append("Offending object: ").append(offendingNode);
}
return new IllegalStateException(msg.toString(), this);
}
}

2
gson/src/main/java/com/google/gson/JsonPrintFormatter.java
View File

@ -17,8 +17,6 @@
package com.google.gson;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;
import java.util.Stack;
/**

82
gson/src/main/java/com/google/gson/JsonSerializationVisitor.java
View File

@ -54,7 +54,7 @@ final class JsonSerializationVisitor implements ObjectNavigator.Visitor {
return;
}
if (ancestors.contains(node)) {
throw new IllegalStateException("Circular reference found: " + node);
throw new CircularReferenceException(node);
}
ancestors.push(node);
}
@ -85,27 +85,35 @@ final class JsonSerializationVisitor implements ObjectNavigator.Visitor {
}
public void visitArrayField(Field f, Type typeOfF, Object obj) {
if (isFieldNull(f, obj)) {
if (serializeNulls) {
addChildAsElement(f, JsonNull.createJsonNull());
try {
if (isFieldNull(f, obj)) {
if (serializeNulls) {
addChildAsElement(f, JsonNull.createJsonNull());
}
} else {
Object array = getFieldValue(f, obj);
addAsChildOfObject(f, typeOfF, array);
}
} else {
Object array = getFieldValue(f, obj);
addAsChildOfObject(f, typeOfF, array);
} catch (CircularReferenceException e) {
throw e.createDetailedException(f);
}
}
public void visitObjectField(Field f, Type typeOfF, Object obj) {
if (isFieldNull(f, obj)) {
if (serializeNulls) {
addChildAsElement(f, JsonNull.createJsonNull());
try {
if (isFieldNull(f, obj)) {
if (serializeNulls) {
addChildAsElement(f, JsonNull.createJsonNull());
}
} else {
Object fieldValue = getFieldValue(f, obj);
if (fieldValue != null) {
typeOfF = getActualTypeIfMoreSpecific(typeOfF, fieldValue.getClass());
}
addAsChildOfObject(f, typeOfF, fieldValue);
}
} else {
Object fieldValue = getFieldValue(f, obj);
if (fieldValue != null) {
typeOfF = getActualTypeIfMoreSpecific(typeOfF, fieldValue.getClass());
}
addAsChildOfObject(f, typeOfF, fieldValue);
} catch (CircularReferenceException e) {
throw e.createDetailedException(f);
}
}
@ -160,20 +168,34 @@ final class JsonSerializationVisitor implements ObjectNavigator.Visitor {
@SuppressWarnings("unchecked")
public boolean visitUsingCustomHandler(Object obj, Type objType) {
JsonSerializer serializer = serializers.getHandlerFor(objType);
if (serializer == null && obj != null) {
serializer = serializers.getHandlerFor(obj.getClass());
}
if (serializer != null) {
if (obj == null) {
assignToRoot(JsonNull.createJsonNull());
} else {
assignToRoot(serializer.serialize(obj, objType, context));
try {
JsonSerializer serializer = serializers.getHandlerFor(objType);
if (serializer == null && obj != null) {
serializer = serializers.getHandlerFor(obj.getClass());
}
return true;
if (serializer != null) {
if (obj == null) {
assignToRoot(JsonNull.createJsonNull());
} else {
assignToRoot(invokeCustomHandler(obj, objType, serializer));
}
return true;
}
return false;
} catch (CircularReferenceException e) {
throw e.createDetailedException(null);
}
}
@SuppressWarnings("unchecked")
private JsonElement invokeCustomHandler(Object obj, Type objType, JsonSerializer serializer) {
start(obj);
try {
return serializer.serialize(obj, objType, context);
} finally {
end(obj);
}
return false;
}
@SuppressWarnings("unchecked")
@ -189,13 +211,15 @@ final class JsonSerializationVisitor implements ObjectNavigator.Visitor {
}
JsonSerializer serializer = serializers.getHandlerFor(actualTypeOfField);
if (serializer != null) {
JsonElement child = serializer.serialize(obj, actualTypeOfField, context);
JsonElement child = invokeCustomHandler(obj, actualTypeOfField, serializer);
addChildAsElement(f, child);
return true;
}
return false;
} catch (IllegalAccessException e) {
throw new RuntimeException();
} catch (CircularReferenceException e) {
throw e.createDetailedException(f);
}
}

131
gson/src/test/java/com/google/gson/functional/CircularReferenceTest.java Normal file
View File

@ -0,0 +1,131 @@
/*
* Copyright (C) 2008 Google Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.google.gson.functional;
import java.lang.reflect.Type;
import java.util.ArrayList;
import java.util.Collection;
import junit.framework.TestCase;
import com.google.gson.Gson;
import com.google.gson.GsonBuilder;
import com.google.gson.JsonElement;
import com.google.gson.JsonObject;
import com.google.gson.JsonSerializationContext;
import com.google.gson.JsonSerializer;
import com.google.gson.common.TestTypes.ClassOverridingEquals;
/**
* Functional tests related to circular reference detection and error reporting.
*
* @author Inderjeet Singh
* @author Joel Leitch
*/
public class CircularReferenceTest extends TestCase {
private Gson gson;
@Override
protected void setUp() throws Exception {
super.setUp();
gson = new Gson();
}
public void testCircularSerialization() throws Exception {
ContainsReferenceToSelfType a = new ContainsReferenceToSelfType();
ContainsReferenceToSelfType b = new ContainsReferenceToSelfType();
a.children.add(b);
b.children.add(a);
try {
gson.toJson(a);
fail("Circular types should not get printed!");
} catch (IllegalStateException expected) {
assertTrue(expected.getMessage().contains("children"));
}
}
public void testSelfReferenceSerialization() throws Exception {
ClassOverridingEquals objA = new ClassOverridingEquals();
objA.ref = objA;
try {
gson.toJson(objA);
fail("Circular reference to self can not be serialized!");
} catch (IllegalStateException expected) { }
}
public void testSelfReferenceArrayFieldSerialization() throws Exception {
ClassWithSelfReferenceArray objA = new ClassWithSelfReferenceArray();
objA.children = new ClassWithSelfReferenceArray[]{objA};
try {
gson.toJson(objA);
fail("Circular reference to self can not be serialized!");
} catch (IllegalStateException expected) {
assertTrue(expected.getMessage().contains("children"));
}
}
public void testSelfReferenceCustomHandlerSerialization() throws Exception {
ClassWithSelfReference obj = new ClassWithSelfReference();
obj.child = obj;
Gson gson = new GsonBuilder().registerTypeAdapter(ClassWithSelfReference.class, new JsonSerializer<ClassWithSelfReference>() {
public JsonElement serialize(ClassWithSelfReference src, Type typeOfSrc,
JsonSerializationContext context) {
JsonObject obj = new JsonObject();
obj.addProperty("property", "value");
obj.add("child", context.serialize(src.child));
return obj;
}
}).create();
try {
gson.toJson(obj);
fail("Circular reference to self can not be serialized!");
} catch (IllegalStateException expected) {
assertTrue(expected.getMessage().contains("Offending"));
}
}
public void testDirectedAcyclicGraphSerialization() throws Exception {
ContainsReferenceToSelfType a = new ContainsReferenceToSelfType();
ContainsReferenceToSelfType b = new ContainsReferenceToSelfType();
ContainsReferenceToSelfType c = new ContainsReferenceToSelfType();
a.children.add(b);
a.children.add(c);
b.children.add(c);
assertNotNull(gson.toJson(a));
}
public void testDirectedAcyclicGraphDeserialization() throws Exception {
String json = "{\"children\":[{\"children\":[{\"children\":[]}]},{\"children\":[]}]}";
ContainsReferenceToSelfType target = gson.fromJson(json, ContainsReferenceToSelfType.class);
assertNotNull(target);
assertEquals(2, target.children.size());
}
private static class ContainsReferenceToSelfType {
Collection<ContainsReferenceToSelfType> children = new ArrayList<ContainsReferenceToSelfType>();
}
private static class ClassWithSelfReference {
ClassWithSelfReference child;
}
private static class ClassWithSelfReferenceArray {
@SuppressWarnings("unused")
ClassWithSelfReferenceArray[] children;
}
}

52
gson/src/test/java/com/google/gson/functional/ObjectTest.java
View File

@ -28,7 +28,6 @@ import com.google.gson.InstanceCreator;
import com.google.gson.common.TestTypes.ArrayOfObjects;
import com.google.gson.common.TestTypes.BagOfPrimitiveWrappers;
import com.google.gson.common.TestTypes.BagOfPrimitives;
import com.google.gson.common.TestTypes.ClassOverridingEquals;
import com.google.gson.common.TestTypes.ClassWithArray;
import com.google.gson.common.TestTypes.ClassWithNoFields;
import com.google.gson.common.TestTypes.ClassWithObjects;
@ -91,23 +90,6 @@ public class ObjectTest extends TestCase {
assertEquals(jsonString, target.getExpectedJson());
}
public void testDirectedAcyclicGraphSerialization() throws Exception {
ContainsReferenceToSelfType a = new ContainsReferenceToSelfType();
ContainsReferenceToSelfType b = new ContainsReferenceToSelfType();
ContainsReferenceToSelfType c = new ContainsReferenceToSelfType();
a.children.add(b);
a.children.add(c);
b.children.add(c);
assertNotNull(gson.toJson(a));
}
public void testDirectedAcyclicGraphDeserialization() throws Exception {
String json = "{\"children\":[{\"children\":[{\"children\":[]}]},{\"children\":[]}]}";
ContainsReferenceToSelfType target = gson.fromJson(json, ContainsReferenceToSelfType.class);
assertNotNull(target);
assertEquals(2, target.children.size());
}
public void testClassWithTransientFieldsSerialization() throws Exception {
ClassWithTransientFields<Long> target = new ClassWithTransientFields<Long>(1L);
assertEquals(target.getExpectedJson(), gson.toJson(target));
@ -231,11 +213,15 @@ public class ObjectTest extends TestCase {
public void testEmptyCollectionInAnObjectDeserialization() throws Exception {
String json = "{\"children\":[]}";
ContainsReferenceToSelfType target = gson.fromJson(json, ContainsReferenceToSelfType.class);
ClassWithCollectionField target = gson.fromJson(json, ClassWithCollectionField.class);
assertNotNull(target);
assertTrue(target.children.isEmpty());
}
private static class ClassWithCollectionField {
Collection<String> children = new ArrayList<String>();
}
public void testPrimitiveArrayInAnObjectDeserialization() throws Exception {
String json = "{\"longArray\":[0,1,2,3,4,5,6,7,8,9]}";
PrimitiveArray target = gson.fromJson(json, PrimitiveArray.class);
@ -252,31 +238,10 @@ public class ObjectTest extends TestCase {
}
public void testEmptyCollectionInAnObjectSerialization() throws Exception {
ContainsReferenceToSelfType target = new ContainsReferenceToSelfType();
ClassWithCollectionField target = new ClassWithCollectionField();
assertEquals("{\"children\":[]}", gson.toJson(target));
}
public void testCircularSerialization() throws Exception {
ContainsReferenceToSelfType a = new ContainsReferenceToSelfType();
ContainsReferenceToSelfType b = new ContainsReferenceToSelfType();
a.children.add(b);
b.children.add(a);
try {
gson.toJson(a);
fail("Circular types should not get printed!");
} catch (IllegalStateException expected) { }
}
public void testSelfReferenceSerialization() throws Exception {
ClassOverridingEquals objA = new ClassOverridingEquals();
objA.ref = objA;
try {
gson.toJson(objA);
fail("Circular reference to self can not be serialized!");
} catch (IllegalStateException expected) { }
}
public void testPrivateNoArgConstructorDeserialization() throws Exception {
ClassWithPrivateNoArgsConstructor target =
gson.fromJson("{\"a\":20}", ClassWithPrivateNoArgsConstructor.class);
@ -339,11 +304,6 @@ public class ObjectTest extends TestCase {
}
}
private static class ContainsReferenceToSelfType {
public Collection<ContainsReferenceToSelfType> children =
new ArrayList<ContainsReferenceToSelfType>();
}
private static class ArrayOfArrays {
private final BagOfPrimitives[][] elements;
public ArrayOfArrays() {