JSONObject、 JsonObject、阿里fastJson、谷歌gson區別

時間 2020-07-23

標籤 jsonobject 阿里 fastjson 谷歌 gson 區別欄目 JSON 简体版

原文原文鏈接

JSON：JavaScript Object Notation Java對象表示法

Java中並無內置的 JSON 解析，須要使用第三方類庫。經常使用的類庫以下html

1、Gson ：古河開發的JSON 庫java

2、FastJson ：阿里巴巴的JSON 庫json

3、JackSon ：社區十分活躍數組

JSONObject 是json 對象，一個鍵對應一個值，例如： {「key」:"value"}ide

1、com.alibaba.fastjson.JsonObject（參考）

1.添加fastJson依賴ui

<dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.2.58</version>
</dependency>

2.將 List 對象轉換爲 Json 格式的Stringthis

List<User> users= findAllUser(); String str = JSONObject.toJSONString(users);

3.將 Map 對象轉換爲 JsonObjectgoogle

Map<String,Object> map = new HashMap(); map.put("name","zhangsan"); map.put("age","15"); JSONObject jsonObject = new JSONObject(map);

4.將Map 轉換爲 Json 格式的String 字符串spa

String jsonStr = JSON.toJSONString(map);

5.將 json 格式的String 字符串轉換爲 Map .net

String jsonStr = "{\"name\":\"zhangsan\",\"age\":\"15\"}"; JSONObject jsonObject = JSONObject.parseObject(jsonStr); Map<String,Object> map = jsonObject;

6. 將 json 格式的字符串轉換爲 JsonObject

String jsonStr = "{\"name\":\"zhangsan\",\"age\":\"15\"}"; JSONObject jsonObject = JSON.parseObject(jsonStr);

7. 將 json字符串轉換爲 Java對象

String jsonStr = "{\"name\":\"zhangsan\",\"email\":\"15\"}"; User user = JSON.parseObject(jsonStr,User.class);

8. 將 json 字符串轉換爲 JSONArray 數組

String jsonStr = "[{\"name\":\"zhangsan\",\"email\":\"zhangsan@qq.com\"},{\"name\":\"lisi\",\"email\":\"lisi@163.com\"}]"; JSONArray array = JSON.parseArray(jsonStr); for(int i=0;i<array.size();i++){ System.out.println(array.get(i)); }

9. 將Java 對象轉換爲 json 字符串

User user = new User(11,"wangwu","wangwu@163.com","上海"); String str = JSON.toJSONString(user);

10. 將json 字符串轉換爲 Java 實體集合

String jsonStr = "[{\"name\":\"zhangsan\",\"email\":\"zhangsan@qq.com\"},{\"name\":\"lisi\",\"email\":\"lisi@163.com\"}]";
 List<User> list = JSON.parseArray(jsonStr,User.class);

11. 將 java 對象轉換爲 JsonObject

User user = new User(11,"wangwu","wangwu@163.com","上海"); JSONObject jsonObject = (JSONObject) JSON.toJSON(user);

2、org.json.JSONObject

1.添加依賴

　<dependency>
            <groupId>org.json</groupId>
            <artifactId>json</artifactId>
            <version>20180130</version>
 </dependency>

2.Bean 對象轉換爲 JSONObject

User user = new User(11,"wangwu","wangwu@163.com","上海"); JSONObject jsonObject = new JSONObject(user);

3.Map 集合轉換爲 JSONObject 對象

Map<String,Object> map = new HashMap(); map.put("name","zhangsan"); map.put("age","15"); JSONObject jsonObject = new JSONObject(map);

4.JSONObject 轉換爲 Map<String,Object>對象

JSONObject jsonObject = new JSONObject();
 jsonObject.toMap();

3、GSON（參考）

1.添加依賴

<dependency>
     <groupId>com.google.code.gson</groupId>
     <artifactId>gson</artifactId>
     <version>2.3.1</version>
  </dependency>

2.Gson 的兩個基礎方法

toJson(); fromJson();

3.建立方式一：

// 使用new方法
Gson gson = new Gson(); // toJson 將bean對象轉換爲json字符串
String jsonStr = gson.toJson(user, User.class); // fromJson 將json字符串轉爲bean對象
Student user= gson.fromJson(jsonStr, User.class); // **序列化List**
String jsonStr2 = gson.toJson(list); // **反序列化成List時須要使用到TypeToken getType()**
List<User> retList = gson.fromJson(jsonStr2,new TypeToken<List<User>>(){}.getType());

建立方式二：

//serializeNulls()是GsonBuilder提供的一種配置，當字段值爲空或null時，依然對該字段進行轉換
Gson gson = new GsonBuilder().serializeNulls().create();

使用GsonBuilder建立Gson實例的步驟：

首先建立GsonBuilder,而後調用GsonBuilder提供的各類配置方法進行配置，最後調用GsonBuilder的create方法，將基於當前的配置建立一個Gson實例。

附錄00：

 1 package entity;  2 
 3 /**
 4  * Created by baizhuang on 2019/9/23 16:29.  5  */
 6 
 7 public class User {  8     private int id;  9     private String name; 10     private String email; 11     private String address; 12 
13     public User() { 14  } 15 
16     public User(int id, String name, String email, String address) { 17         this.id = id; 18         this.name = name; 19         this.email = email; 20         this.address = address; 21  } 22 
23  @Override 24     public String toString() { 25         return "User{" +
26                 "id=" + id +
27                 ", name='" + name + '\'' +
28                 ", email='" + email + '\'' +
29                 ", address='" + address + '\'' +
30                 '}'; 31  } 32 
33     public int getId() { 34         return id; 35  } 36 
37     public void setId(int id) { 38         this.id = id; 39  } 40 
41     public String getName() { 42         return name; 43  } 44 
45     public void setName(String name) { 46         this.name = name; 47  } 48 
49     public String getEmail() { 50         return email; 51  } 52 
53     public void setEmail(String email) { 54         this.email = email; 55  } 56 
57     public String getAddress() { 58         return address; 59  } 60 
61     public void setAddress(String address) { 62         this.address = address; 63  } 64 }

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附錄01：

 1 package entity;  2 
 3 import com.alibaba.fastjson.JSON;  4 import com.alibaba.fastjson.JSONArray;  5 import com.alibaba.fastjson.JSONObject;  6 import java.util.Arrays;  7 import java.util.HashMap;  8 import java.util.List;  9 import java.util.Map;  10 
 11 /**
 12  * Created by baizhuang on 2019/9/23 16:30.  13  */
 14 
 15 public class Test {  16 
 17     public static List<User> findAllUser(){  18         return Arrays.asList(  19                 new User(1,"zhangsan","zhang","北京"),  20                 new User(2,"lisi","li","上海"));  21 
 22  }  23 
 24 
 25     public static void listToJsonString(){  26         List<User> users= findAllUser();  27 
 28  System.out.println(users);  29 
 30         String str = JSONObject.toJSONString(users);  31 
 32  System.out.println(str);  33  }  34 
 35 
 36     public static  void maptoJsonObject(){  37         Map<String,Object> map = new HashMap();  38         map.put("name","zhangsan");  39         map.put("age","15");  40         JSONObject jsonObject = new JSONObject(map);  41         System.out.printf("Json:"+jsonObject);  42 
 43         String jsonStr = JSON.toJSONString(map);  44  System.out.println(jsonStr);  45 
 46  }  47 
 48 
 49     public static void stringToMap(){  50 
 51         String jsonStr = "{\"name\":\"zhangsan\",\"age\":\"15\"}";  52 
 53         JSONObject  jsonObject = JSONObject.parseObject(jsonStr);  54 
 55         Map<String,Object> map = jsonObject;  56 
 57  }  58 
 59 
 60     public static  void jsonToJsonObject(){  61         String jsonStr = "{\"name\":\"zhangsan\",\"age\":\"15\"}";  62 
 63         JSONObject jsonObject = JSON.parseObject(jsonStr);  64 
 65  System.out.println(jsonObject);  66  }  67 
 68     public static void jsonStrToJsonBean(){  69         String jsonStr = "{\"name\":\"zhangsan\",\"email\":\"15\"}";  70 
 71         User user = JSON.parseObject(jsonStr,User.class);  72 
 73  System.out.println(user);  74  }  75 
 76     public static void jsonStrToJsonArray(){  77         String jsonStr = "[{\"name\":\"zhangsan\",\"email\":\"zhangsan@qq.com\"},{\"name\":\"lisi\",\"email\":\"lisi@163.com\"}]";  78 
 79         JSONArray array = JSON.parseArray(jsonStr);  80 
 81         for(int i=0;i<array.size();i++){  82  System.out.println(array.get(i));  83  }  84  }  85 
 86     public static void javaBeanToJsonStr(){  87         User user = new User(11,"wangwu","wangwu@163.com","上海");  88 
 89         String str = JSON.toJSONString(user);  90  System.out.println(str);  91  }  92 
 93     public static void jsonStrToBeanList(){  94         String jsonStr = "[{\"name\":\"zhangsan\",\"email\":\"zhangsan@qq.com\"},{\"name\":\"lisi\",\"email\":\"lisi@163.com\"}]";  95         List<User> list = JSON.parseArray(jsonStr,User.class);  96         for(User user : list){  97  System.out.println(user);  98  }  99  } 100 
101     public static void beanToJsonObject(){ 102         User user = new User(11,"wangwu","wangwu@163.com","上海"); 103 
104         JSONObject jsonObject = (JSONObject) JSON.toJSON(user); 105 
106  System.out.println(jsonObject); 107 
108  } 109 
110     public static void main(String []args){ 111         //listToJsonString(); 112         //(); 113        // stringToMap(); 114        // jsonToJsonObject(); 115        // jsonStrToJsonBean(); 116         //jsonStrToJsonArray(); 117        // javaBeanToJsonStr(); 118         //jsonStrToBeanList();
119  beanToJsonObject(); 120 
121  } 122 }

View Code

附錄02：

 1 public class TestOrgJson {  2 
 3     public static void beanToJSONObject(){  4         User user = new User(11,"wangwu","wangwu@163.com","上海");  5 
 6         JSONObject jsonObject = new JSONObject(user);  7 
 8  System.out.println(jsonObject);  9  } 10 
11     public static void mapToJSONObject(){ 12 
13         Map<String,Object> map = new HashMap(); 14         map.put("name","zhangsan"); 15         map.put("age","15"); 16 
17         JSONObject jsonObject = new JSONObject(); 18  jsonObject.toMap(); 19  } 20 
21 
22     public static void main(String []args){ 23 
24 
25 
26  } 27 }