Json-Lib, Org.Json, Jackson, Gson, FastJson five ways to convert json type

Json-Lib, Org.Json, Jackson, Gson, FastJson five ways to convert json type

Only the most convenient way is listed. Replication situation and speed are not involved.

Test case, a User class, attribute name, age, location. Override toString().

 
 
  
  
public class User {
private String name;
private Integer age;
private String location;

public User() {
}
public User(String name) {
this.name = name;
}
public User(String name, Integer age) {
this .name = name;
this.age = age;
}
public User(String name, Integer age, String location) {
this .name = name;
this .age = age;
this.location = location;
}

public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Integer getAge() {
return age;
}
public void setAge(Integer age) {
this.age = age;
}
public String getLocation() {
return location;
}
public void setLocation(String location) {
this.location = location;
}

@Override
public String toString() {
return "User{" +
"name='" + name + '\'' +
", age=" + age +
", location='" + location + '\'' +
'}';
}
}

 
 
  
  

 
 
  
  
1、 Json- Lib
Maven depends on the following, pay attention to <classifier>jdk15</classifier>, jar package distinguishes jdk1. 3 and jdk1. 5 version

<dependency>
<groupId>net.sf.json-lib</groupId>
<artifactId>json-lib</artifactId>
<version> 2.4</version>
<classifier>jdk15</classifier>
</dependency>

test demo

import net.sf.json.JSONObject;

public class JsonLibDemo {

public static void main( String[] args) {
//Create test object
User user = new User( "Li Ning" , 24, "Beijing" );
System.out. println(user);

//Convert to json string
JSONObject jsonObject = JSONObject.fromObject(user);
String json = jsonObject. toString();
System .out. println(json);

//json string to object
JSONObject jsonObject1 = JSONObject.fromObject(json);
User user1 = ( User) JSONObject.toBean(jsonObject1, User. class);
System .out. println(user1);
}
}

 
 
  
  

 

 
 
  
  
2、org.json
The maven dependencies are as follows

<dependency>
<groupId>org.json</groupId>
<artifactId>json</artifactId>
<version> 20170516</version>
</dependency>

test demo

import org.json.JSONObject;

public class OrgJsonDemo {
public static void main(String[] args) {
//Create test object
User user = new User( "Li Ning" , 24, "Beijing" );
System. out.println(user);

//Convert to json string
String json = new JSONObject(user).toString();
System. out.println(json);

//json string to object
JSONObject jsonObject = new JSONObject(json);
String name = jsonObject.getString( "name");
Integer age = jsonObject.getInt( "age");
String location = jsonObject.getString( "location");
User user1 = new User(name,age,location);
System. out.println(user1);
}
}

 
 
  
  

 

 
 
  
  
3、Jackson
maven dependencies

<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-databind</artifactId>
<version> 2.9 .0</version>
</dependency>

test demo

import com.fasterxml.jackson.databind.ObjectMapper;

public class JacksonDemo {
public static void main(String[] args) {
//Create test object
User user = new User( "Li Ning" , 24, "Beijing" );
System. out.println(user);

//Convert to json string
ObjectMapper mapper = new ObjectMapper();
try {
String json = mapper.writeValueAsString(user);
System. out.println(json);


//json string to object
User user1 = mapper.readValue(json,User.class);
System. out.println(user1);

} catch (java.io.IOException e) {
e.printStackTrace();
}
}
}

 
 
  
  

 

 
 
  
  
4、Gson
maven dependencies

<dependency>
<groupId>com.google.code.gson</groupId>
<artifactId>gson</artifactId>
<version> 2.8 .1</version>
</dependency>

test demo

import com.google.gson.Gson;

public class GsonDemo {
public static void main(String[] args) {
//Create test object
User user = new User( "Li Ning" , 24, "Beijing" );
System. out.println(user);

//Convert to json string
Gson gson = new Gson();
String json = gson.toJson(user);
System. out.println(json);

//json string to object
User user1 = gson.fromJson(json,User.class);
System. out.println(user1);
}
}

 
 
  
  

 

 
 
  
  
5、 FastJson
maven dependencies

<dependency>
<groupId>com.alibaba</groupId>
<artifactId>fastjson</artifactId>
<version> 1.2. 37</version>
</dependency>

test demo

import com.alibaba.fastjson.JSON;

public class FastJsonDemo {
public static void main( String[] args) {
//Create test object
User user = new User( "Li Ning" , 24, "Beijing" );
System.out. println(user);

//Convert to json string
String json = JSON.toJSON(user). toString();
System .out. println(json);

//json string to object
User user1 = JSON.parseObject(json, User. class);
System .out. println(user1);

}
}

 
 
  
  

 

The json-lib time is a bit long, and the jar package is only updated to 2010

org.json is a bit cumbersome to use

Jackson, Gson, FastJson can be done in just one or two sentences

Original text from: https://blog.csdn.net/n447194252/article/details/77747465

Json-Lib, Org.Json, Jackson, Gson, FastJson five ways to convert json type