[Java] Java实现Json字符串与Object对象相互转换的方式总结

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 + '\'' +
    '}';
  }
}

<dependency>
 <groupid>net.sf.json-lib</groupid>
 <artifactid>json-lib</artifactid>
 <version>2.4</version>
 <classifier>jdk15</classifier>
</dependency>

import net.sf.json.jsonobject;
public class jsonlibdemo {
  public static void main(string[] args) {
  //创建测试object
  user user = new user("李宁",24,"北京");
  system.out.println(user);
  //转成json字符串
  jsonobject jsonobject = jsonobject.fromobject(user);
  string json = jsonobject.tostring();
  system.out.println(json);
  //json字符串转成对象
  jsonobject jsonobject1 = jsonobject.fromobject(json);
  user user1 = (user) jsonobject.tobean(jsonobject1,user.class);
  system.out.println(user1);
  }
}

<dependency>
 <groupid>org.json</groupid>
 <artifactid>json</artifactid>
 <version>20170516</version>
</dependency>

import org.json.jsonobject;
public class orgjsondemo {
  public static void main(string[] args) {
  //创建测试object
  user user = new user("李宁",24,"北京");
  system.out.println(user);
  //转成json字符串
  string json = new jsonobject(user).tostring();
  system.out.println(json);
  //json字符串转成对象
  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);
  }
}

<dependency>
 <groupid>com.fasterxml.jackson.core</groupid>
 <artifactid>jackson-databind</artifactid>
 <version>2.9.0</version>
</dependency>

import com.fasterxml.jackson.databind.objectmapper;
public class jacksondemo {
  public static void main(string[] args) {
  //创建测试object
  user user = new user("李宁",24,"北京");
  system.out.println(user);
  //转成json字符串
  objectmapper mapper = new objectmapper();
  try {
    string json = mapper.writevalueasstring(user);
    system.out.println(json);
    //json字符串转成对象
    user user1 = mapper.readvalue(json,user.class);
    system.out.println(user1);
  } catch (java.io.ioexception e) {
    e.printstacktrace();
  }
  }
}

<dependency>
 <groupid>com.google.code.gson</groupid>
 <artifactid>gson</artifactid>
 <version>2.8.1</version>
</dependency>

import com.google.gson.gson;
public class gsondemo {
  public static void main(string[] args) {
  //创建测试object
  user user = new user("李宁",24,"北京");
  system.out.println(user);
  //转成json字符串
  gson gson = new gson();
  string json = gson.tojson(user);
  system.out.println(json);
  //json字符串转成对象
  user user1 = gson.fromjson(json,user.class);
  system.out.println(user1);
  }
}

<dependency>
 <groupid>com.alibaba</groupid>
 <artifactid>fastjson</artifactid>
 <version>1.2.37</version>
</dependency>

import com.alibaba.fastjson.json;
public class fastjsondemo {
  public static void main(string[] args) {
  //创建测试object
  user user = new user("李宁",24,"北京");
  system.out.println(user);
  //转成json字符串
  string json = json.tojson(user).tostring();
  system.out.println(json);
  //json字符串转成对象
  user user1 = json.parseobject(json,user.class);
  system.out.println(user1);
  }
}