gson-comments/gson/src/test/java/com/google/gson/functional/MapTest.java

/*
 * 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 com.google.gson.Gson;
import com.google.gson.GsonBuilder;
import com.google.gson.InstanceCreator;
import com.google.gson.reflect.TypeToken;

import junit.framework.TestCase;

import java.lang.reflect.Type;
import java.util.Collection;
import java.util.HashMap;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.TreeMap;

/**
 * Functional test for Json serialization and deserialization for Maps
 *
 * @author Inderjeet Singh
 * @author Joel Leitch
 */
public class MapTest extends TestCase {
  private Gson gson;

  @Override
  protected void setUp() throws Exception {
    super.setUp();
    gson = new Gson();
  }

  public void testMapSerialization() {
    Map<String, Integer> map = new LinkedHashMap<String, Integer>();
    map.put("a", 1);
    map.put("b", 2);
    Type typeOfMap = new TypeToken<Map<String, Integer>>() {}.getType();
    String json = gson.toJson(map, typeOfMap);
    assertTrue(json.contains("\"a\":1"));
    assertTrue(json.contains("\"b\":2"));
  }

  public void testMapDeserialization() {
    String json = "{\"a\":1,\"b\":2}";
    Type typeOfMap = new TypeToken<Map<String,Integer>>(){}.getType();
    Map<String, Integer> target = gson.fromJson(json, typeOfMap);
    assertEquals(1, target.get("a").intValue());
    assertEquals(2, target.get("b").intValue());
  }

  @SuppressWarnings({ "unchecked", "rawtypes" })
  public void testRawMapSerialization() {
    Map map = new LinkedHashMap();
    map.put("a", 1);
    map.put("b", "string");
    String json = gson.toJson(map);
    assertTrue(json.contains("\"a\":1"));
    assertTrue(json.contains("\"b\":\"string\""));    
  }
  
  public void testMapSerializationEmpty() {
    Map<String, Integer> map = new LinkedHashMap<String, Integer>();
    Type typeOfMap = new TypeToken<Map<String, Integer>>() {}.getType();
    String json = gson.toJson(map, typeOfMap);
    assertEquals("{}", json);
  }
  
  public void testMapDeserializationEmpty() {
    Type typeOfMap = new TypeToken<Map<String, Integer>>() {}.getType();
    Map<String, Integer> map = gson.fromJson("{}", typeOfMap);
    assertTrue(map.isEmpty());
  }
  
  public void testMapSerializationWithNullValue() {
    Map<String, Integer> map = new LinkedHashMap<String, Integer>();
    map.put("abc", null);
    Type typeOfMap = new TypeToken<Map<String, Integer>>() {}.getType();
    String json = gson.toJson(map, typeOfMap);
    
    // Maps are represented as JSON objects, so ignoring null field
    assertEquals("{}", json);
  }
  
  public void testMapDeserializationWithNullValue() {
    Type typeOfMap = new TypeToken<Map<String, Integer>>() {}.getType();
    Map<String, Integer> map = gson.fromJson("{\"abc\":null}", typeOfMap);
    assertEquals(1, map.size());
    assertNull(map.get("abc"));
  }
  
  public void testMapSerializationWithNullValueButSerializeNulls() {
    gson = new GsonBuilder().serializeNulls().create();
    Map<String, Integer> map = new LinkedHashMap<String, Integer>();
    map.put("abc", null);
    Type typeOfMap = new TypeToken<Map<String, Integer>>() {}.getType();
    String json = gson.toJson(map, typeOfMap);

    assertEquals("{\"abc\":null}", json);
  }
  
  public void testMapSerializationWithNullKey() {
    Map<String, Integer> map = new LinkedHashMap<String, Integer>();
    map.put(null, 123);
    Type typeOfMap = new TypeToken<Map<String, Integer>>() {}.getType();
    String json = gson.toJson(map, typeOfMap);

    assertEquals("{\"null\":123}", json);
  }
  
  public void testMapDeserializationWithNullKey() {
    Type typeOfMap = new TypeToken<Map<String, Integer>>() {}.getType();
    Map<String, Integer> map = gson.fromJson("{\"null\":123}", typeOfMap);
    assertEquals(1, map.size());
    assertNull(map.get(null));
  }
  
  public void testMapSerializationWithIntegerKeys() {
    Map<Integer, String> map = new LinkedHashMap<Integer, String>();
    map.put(123, "456");
    Type typeOfMap = new TypeToken<Map<Integer, String>>() {}.getType();
    String json = gson.toJson(map, typeOfMap);

    assertEquals("{\"123\":\"456\"}", json);
  }
  
  public void testMapDeserializationWithIntegerKeys() {
    Type typeOfMap = new TypeToken<Map<Integer, String>>() {}.getType();
    Map<Integer, String> map = gson.fromJson("{\"123\":\"456\"}", typeOfMap);
    assertEquals(1, map.size());
    assertTrue(map.containsKey(123));
    assertEquals("456", map.get(123));
  }

  public void testParameterizedMapSubclassSerialization() {
    MyParameterizedMap<String, String> map = new MyParameterizedMap<String, String>();
    map.put("a", "b");
    Type type = new TypeToken<MyParameterizedMap<String, String>>() {}.getType();
    String json = gson.toJson(map, type);
    assertTrue(json.contains("\"a\":\"b\""));
  }

  @SuppressWarnings("rawtypes")
  public void testParameterizedMapSubclassDeserialization() {
    Type type = new TypeToken<MyParameterizedMap<String, Integer>>() {}.getType();
    Gson gson = new GsonBuilder().registerTypeAdapter(type, 
        new InstanceCreator<MyParameterizedMap>() {
      public MyParameterizedMap createInstance(Type type) {
        return new MyParameterizedMap();
      }      
    }).create();
    String json = "{\"a\":1,\"b\":2}";
    MyParameterizedMap<String, Integer> map = gson.fromJson(json, type);
    assertEquals(1, map.get("a").intValue()); 
    assertEquals(2, map.get("b").intValue()); 
  }

  private static class MyParameterizedMap<K, V> extends LinkedHashMap<K, V> {
    private static final long serialVersionUID = 1L;

    @SuppressWarnings("unused")
    int foo = 10;
  }
  
  public void testMapSubclassSerialization() {
    MyMap map = new MyMap();
    map.put("a", "b");
    String json = gson.toJson(map, MyMap.class);
    assertTrue(json.contains("\"a\":\"b\""));
  }
  
  public void testMapStandardSubclassDeserialization() {
    String json = "{a:'1',b:'2'}";
    Type type = new TypeToken<LinkedHashMap<String, String>>() {}.getType();
    LinkedHashMap<String, Integer> map = gson.fromJson(json, type);
    assertEquals("1", map.get("a")); 
    assertEquals("2", map.get("b")); 
  }
  
  public void disable_testMapSubclassDeserialization() {
    Gson gson = new GsonBuilder().registerTypeAdapter(MyMap.class, new InstanceCreator<MyMap>() {
      public MyMap createInstance(Type type) {
        return new MyMap();
      }      
    }).create();
    String json = "{\"a\":1,\"b\":2}";
    MyMap map = gson.fromJson(json, MyMap.class);
    assertEquals("1", map.get("a")); 
    assertEquals("2", map.get("b")); 
  }
  
  /**
   * Created in response to http://code.google.com/p/google-gson/issues/detail?id=99
   */
  private static class ClassWithAMap {
    Map<String, String> map = new TreeMap<String, String>();
  }
  
  /**
   * Created in response to http://code.google.com/p/google-gson/issues/detail?id=99
   */
  public void testMapSerializationWithNullValues() {
    ClassWithAMap target = new ClassWithAMap();
    target.map.put("name1", null);
    target.map.put("name2", "value2");
    String json = gson.toJson(target);
    assertFalse(json.contains("name1"));
    assertTrue(json.contains("name2"));
  }
  
  /**
   * Created in response to http://code.google.com/p/google-gson/issues/detail?id=99
   */
  public void testMapSerializationWithNullValuesSerialized() {
    Gson gson = new GsonBuilder().serializeNulls().create();
    ClassWithAMap target = new ClassWithAMap();
    target.map.put("name1", null);
    target.map.put("name2", "value2");
    String json = gson.toJson(target);
    assertTrue(json.contains("name1"));
    assertTrue(json.contains("name2"));
  }
  
  public void testMapSerializationWithWildcardValues() {
    Map<String, ? extends Collection<? extends Integer>> map =
        new LinkedHashMap<String, Collection<Integer>>();
    map.put("test", null);
    Type typeOfMap = 
        new TypeToken<Map<String, ? extends Collection<? extends Integer>>>() {}.getType();
    String json = gson.toJson(map, typeOfMap);

    assertEquals("{}", json);
  }
  
  public void testMapDeserializationWithWildcardValues() {
    Type typeOfMap = new TypeToken<Map<String, ? extends Long>>() {}.getType();
    Map<String, ? extends Long> map = gson.fromJson("{\"test\":123}", typeOfMap);
    assertEquals(1, map.size());
    assertEquals(new Long(123L), map.get("test"));
  }

  
  private static class MyMap extends LinkedHashMap<String, String> {
    private static final long serialVersionUID = 1L;

    @SuppressWarnings("unused")
    int foo = 10;
  }
  
  /**
   * From bug report http://code.google.com/p/google-gson/issues/detail?id=95
   */
  public void testMapOfMapSerialization() {
    Map<String, Map<String, String>> map = new HashMap<String, Map<String, String>>();
    Map<String, String> nestedMap = new HashMap<String, String>();
    nestedMap.put("1", "1");
    nestedMap.put("2", "2");
    map.put("nestedMap", nestedMap);
    String json = gson.toJson(map);
    assertTrue(json.contains("nestedMap"));
    assertTrue(json.contains("\"1\":\"1\""));
    assertTrue(json.contains("\"2\":\"2\""));
  }
  
  /**
   * From bug report http://code.google.com/p/google-gson/issues/detail?id=95
   */
  public void testMapOfMapDeserialization() {
    String json = "{nestedMap:{'2':'2','1':'1'}}";
    Type type = new TypeToken<Map<String, Map<String, String>>>(){}.getType();
    Map<String, Map<String, String>> map = gson.fromJson(json, type);
    Map<String, String> nested = map.get("nestedMap");
    assertEquals("1", nested.get("1"));
    assertEquals("2", nested.get("2"));
  }

  /**
   * From bug report http://code.google.com/p/google-gson/issues/detail?id=178
   */
  public void testMapWithQuotes() {
    Map<String, String> map = new HashMap<String, String>();
    map.put("a\"b", "c\"d");
    String json = gson.toJson(map);
    assertEquals("{\"a\\\"b\":\"c\\\"d\"}", json);
  }
}