Java实现Json字符串与Object对象相互转换的方式总结

时间:2022-10-22 13:40:02

本文实例总结了java实现json字符串与object对象相互转换的方式。分享给大家供大家参考,具体如下:

json-lib、org.json、jackson、gson、fastjson五种方式转换json类型

只列举了最省事的方式。不涉及复制情况和速度。

测试用例,一个user类,属性name,age,location。重写tostring()。

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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依赖如下,需注意<classifier>jdk15</classifier>,jar包区分jdk1.3和jdk1.5版本

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

测试demo

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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);
  }
}

2、org.json

maven依赖如下

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

测试demo

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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);
  }
}

3、jackson

maven依赖

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

测试demo

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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();
    }
  }
}

4、gson

maven依赖

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

测试demo

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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);
  }
}

5、fastjson

maven依赖

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

测试demo

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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);
  }
}

json-lib时间有些久远,jar包只更新到2010年

org.json用起来有些繁琐

jackson、gson、fastjson只需一两句话就可以搞定

ps:关于json操作,这里再为大家推荐几款比较实用的json在线工具供大家参考使用:

在线json代码检验、检验、美化、格式化工具:https://tool.zzvips.com/t/jsonjiexi/

json在线格式化工具:https://tool.zzvips.com/t/jsonformat/

在线excel/json互相转换工具:https://tool.zzvips.com/t/excel2json/

json/excel互相转换工具:https://tool.zzvips.com/t/json2excel/

在线json压缩/转义工具:https://tool.zzvips.com/t/jsonzip/

希望本文所述对大家java程序设计有所帮助。

原文链接:https://blog.csdn.net/n447194252/article/details/77747465