初识 JSONArray的用法

使用 fastjson-1.2.4.jar，一个解析json字符串jar包，由阿里巴巴工程师开发。

package com.godcin.test.bean;

import java.util.List;

public class User {
    private String name;
    private int age;
    private List<String> habits;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    public List<String> getHabits() {
        return habits;
    }

    public void setHabits(List<String> habits) {
        this.habits = habits;
    }

}

package com.godcin.test.json;

import java.util.ArrayList;
import java.util.List;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONArray;
import com.godcin.test.bean.User;

public class jsonArrayTest {
    public static void main(String[] args) {
        User user1 = new User();
        user1.setName("张三");
        user1.setAge(18);
        List<String> habits1 = new ArrayList<String>();
        habits1.add("抽烟");
        habits1.add("喝酒");
        user1.setHabits(habits1);

        User user2 = new User();
        user2.setName("李四");
        user2.setAge(18);
        List<String> habits2 = new ArrayList<String>();
        habits2.add("打牌");
        habits2.add("唱歌");
        user2.setHabits(habits2);

        List<User> users=new ArrayList<User>();
        users.add(user1);
        users.add(user2);

        JSONArray jsonArray=new JSONArray();//1、创建JSONArray
        jsonArray.addAll(users);//2、把JSONArray添加List,List<User>转JSONArray
        System.out.println(jsonArray.get(0));//输出结果|[email protected]
        System.out.println(jsonArray.get(1));//输出结果|[email protected]
        System.out.println("姓名："+((User)jsonArray.get(0)).getName());//输出结果|姓名：张三
        System.out.println("爱好："+((User)jsonArray.get(1)).getHabits());//输出结果|爱好：[打牌, 唱歌]

        String jsonStr=jsonArray.toJSONString();//3、JSONArray转化json字符串
        System.out.println(jsonStr);//输出结果|[{"age":18,"habits":["抽烟","喝酒"],"name":"张三"},{"age":18,"habits":["抽烟","喝酒"],"name":"张三"}]

        users=JSON.parseArray(jsonStr, User.class);//json字符串转List<User>
        System.out.println(users);//输出结果 |[[email protected], [email protected]]

    }

}