1 /* 2 * Copyright (C) 2008 Google Inc. 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package com.google.gson; 18 19 import com.google.gson.reflect.TypeToken; 20 import java.lang.reflect.Type; 21 import java.util.HashMap; 22 import java.util.Map; 23 import junit.framework.TestCase; 24 25 /** 26 * Unit test for the default JSON map serialization object located in the 27 * {@link DefaultTypeAdapters} class. 28 * 29 * @author Joel Leitch 30 */ 31 public class DefaultMapJsonSerializerTest extends TestCase { 32 private Gson gson = new Gson(); 33 testEmptyMapNoTypeSerialization()34 public void testEmptyMapNoTypeSerialization() { 35 Map<String, String> emptyMap = new HashMap<>(); 36 JsonElement element = gson.toJsonTree(emptyMap, emptyMap.getClass()); 37 assertTrue(element instanceof JsonObject); 38 JsonObject emptyMapJsonObject = (JsonObject) element; 39 assertTrue(emptyMapJsonObject.entrySet().isEmpty()); 40 } 41 testEmptyMapSerialization()42 public void testEmptyMapSerialization() { 43 Type mapType = new TypeToken<Map<String, String>>() { }.getType(); 44 Map<String, String> emptyMap = new HashMap<>(); 45 JsonElement element = gson.toJsonTree(emptyMap, mapType); 46 47 assertTrue(element instanceof JsonObject); 48 JsonObject emptyMapJsonObject = (JsonObject) element; 49 assertTrue(emptyMapJsonObject.entrySet().isEmpty()); 50 } 51 testNonEmptyMapSerialization()52 public void testNonEmptyMapSerialization() { 53 Type mapType = new TypeToken<Map<String, String>>() { }.getType(); 54 Map<String, String> myMap = new HashMap<>(); 55 String key = "key1"; 56 myMap.put(key, "value1"); 57 Gson gson = new Gson(); 58 JsonElement element = gson.toJsonTree(myMap, mapType); 59 60 assertTrue(element.isJsonObject()); 61 JsonObject mapJsonObject = element.getAsJsonObject(); 62 assertTrue(mapJsonObject.has(key)); 63 } 64 } 65