alibaba之fastJson常见应用

案例一：

　　json格式字符串转JSONObject对象

package com.sr.biofunet.web.controller.utils;
import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;
public class Test {
    public static void main(String[] args) {
        String jsonData = "{\"id\":\"1\",\"name\":\"张三\"}";
        JSONObject jsonObject = JSON.parseObject(jsonData);
        System.out.println("key:" + jsonObject.getString("id"));
        System.out.println("key:" + jsonObject.get("name"));
    }
}

运行结果

key:1
key:张三

案例二 ：

　　java对象转JSONObject对象

package com.sr.biofunet.web.controller.utils;
import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;

import java.text.SimpleDateFormat;
import java.util.Date;

public class Test {
    public static void main(String[] args) {
        Student s = new Student();
        s.setId(1);
        s.setName("李四");
        s.setBirthday(new Date());
        String jsonData = JSON.toJSONString(s);
        JSONObject jsonObject = JSON.parseObject(jsonData);
        System.out.println(jsonObject.get("name"));
        System.out.println(new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").format(jsonObject.getDate("birthday")));
    }
}

运行结果：

　　李四

　　2017-08-01 15:42:03

 

案例三：

　　Map对象转JSONObject对象

package com.sr.biofunet.web.controller.utils;
import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;
import java.util.Date;
import java.util.HashMap;
public class Test {
    public static void main(String[] args) {
        HashMap<String,String> hashMap = new HashMap<>();
        hashMap.put("a","A");
        hashMap.put("b","B");
        JSONObject jsonObject = JSON.parseObject(JSON.toJSONString(hashMap));
        System.out.println(jsonObject.getString("a"));
        System.out.println(jsonObject.getString("b"));
    }
}

运行结果

　　A

　　B

案例四：

　　java对象转换JSONObject对象跟@JSONField注解的使用

　　次注解的作用是输出json格式数据的时候重新定义json中key的别名

package com.sr.biofunet.web.controller.utils;
import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;
import com.alibaba.fastjson.annotation.JSONField;
import java.util.Date;
public class Test {
    public static void main(String[] args) {
        Student student = new Student();
        student.setBirthday(new Date());
        JSONObject jsonObject = (JSONObject)JSON.toJSON(student);
        System.out.println(jsonObject.getDate("birthday"));
        System.out.println(jsonObject.getDate("json_birthday"));
    }
}
class Student{
    private Integer id;
    private String name;
    private double weight;
    @JSONField(name="json_birthday")
    private Date birthday;
    private char sex;

    public Student(){}
    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

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

    public double getWeight() {
        return weight;
    }

    public void setWeight(double weight) {
        this.weight = weight;
    }

    public Date getBirthday() {
        return birthday;
    }

    public void setBirthday(Date birthday) {
        this.birthday = birthday;
    }

    public char getSex() {
        return sex;
    }

    public void setSex(char sex) {
        this.sex = sex;
    }

    public Student(Integer id, String name, double weight, Date birthday, char sex) {
        this.id = id;
        this.name = name;
        this.weight = weight;
        this.birthday = birthday;
        this.sex = sex;
    }

    @Override
    public String toString() {
        return "Student{" +
                "id=" + id +
                ", name='" + name + '\'' +
                ", weight=" + weight +
                ", birthday=" + birthday +
                ", sex=" + sex +
                '}';
    }
}

输出结果：

　　null

　　Tue Aug 01 16:09:12 CST 2017