class User {

private Long id;

private String name;

private String pwd;

//getter and setter

}

User user = new User();

user.setId(1001L);

user.setName("zhenlging");

user.setPwd("abc");

//解析普通对象

Gson gson = new Gson();

String userStr = gson.toJson(user);

System.out.println(userStr);

//输出结果：{"id":1001,"name":"zhenlging","pwd":"abc"}

//解析Map对象

Map<String, User> userMap = new HashMap<String,User>();

userMap.put("user1", user);

String sUserMap = gson.toJson(userMap, new TypeToken<Map<String,User>>(){}.getType());

System.out.println(sUserMap);

//输出结果：{"user1":{"id":1001,"name":"zhengling","pwd":"aaa"},"user2":{"id": 1002,"name":"yangyang","pwd":"bbb"}}

//解析List对象

List<User> list = new ArrayList<User>();

list.add(user1);

list.add(user2);

String sUserList = gson.toJson(list, new TypeToken<List<User>>(){}.getType());

System.out.println(sUserList);

//输出结果：[{"id":1001,"name":"zhengling","pwd":"aaa"},{"id":1002, "name":"yangyang","pwd":"bbb"}]

class User {

@Expose

private Long id;

private String name;

@Expose

private String pwd;

//getter and setter

}

//解析代码

User user = new User();

user.setId(1001L);

user.setName("zhenlging");

user.setPwd("abc");

GsonBuilder builder = new GsonBuilder();

//不转换没有@Expose注解的字段

builder.excludeFieldsWithoutExposeAnnotation();

Gson gson = builder.create();

String userStr = gson.toJson(user);

System.out.println(userStr);

//输出结果：{"id":1001,"pwd":"abc"}

Gson gson = new Gson();

//普通对象

String str1 = "{"id":1001,"name":"zhenlging","pwd":"abc"}";

User user = gson.fromJson(str1, User.class);

System.out.println("USER_ID: " + user.getId() + ",USER_NAME:" + user.getName() + ",USER_PWD:"+ user.getPwd());

//输出结果：USER_ID: 1001,USER_NAME:zhenlging,USER_PWD:abc

//Map对象

String str2 = "{"user1":{"id":1001,"name":"zhengling","pwd":"aaa"},"user2":" +

"{"id":1002,"name":"yangyang","pwd":"bbb"}}";

Map<String,User> userMap = gson.fromJson(str2, new TypeToken<Map<String, User>>(){}.getType());

System.out.println(userMap.get("user1").getName());

//输出结果：zhengling

//List对象

String str3 = "[{"id":1001,"name":"zhengling","pwd":"aaa"},{"id":1002,"name"" +

":"yangyang","pwd":"bbb"}]";

List<User> userList = gson.fromJson(str3, new TypeToken<List<User>>(){}.getType());

System.out.println(userList.get(1).getName());

//输出结果：yangyang

<script type="text/javascript">

var myJson = '{ "x": "Hello, World!", "y": [1, 2, 3] }';

var myJsonObj = jsonParse(myJson);

document.write(myJsonObj.x+"<br>");

for(var k in myJsonObj) {

document.write(k + '=' + myJsonObj[k]+"<br>");

}

var y = myJsonObj.y;

for(var i in y){

document.write(y[i]+"<br>");

}

</script>

输出结果：

Hello, World!
x=Hello, World!
y=1,2,3
1
2
3