JSONObject和JSONArray使用

1.所依赖JAR包

要使程序可以运行必须引入JSON-lib包，JSON-lib包同时依赖于以下的JAR包：

commons-lang.jar
commons-beanutils.jar
commons-collections.jar
commons-logging.jar
ezmorph.jar
json-lib-2.2.2-jdk15.jar

2.Demo

2.1 应用场景:

后台的java类，如实体类、List、Set、Map转成json字符串发送到其它项目或者jsp端
jsp端或者其它项目发送过来的json字符串，需要解析成l实体类、List、Set、Map等java类

2.2 Student实体类

package json;

import java.util.Date;

import java.util.List;

import java.util.Map;

import java.util.Set;

public class Student {

     private int id;

     private String name;

     private String age;

     private Date birthDay;

     private List list;

     private Set set;

     private Map map;

    public int getId() {

        return id;

    }

    public void setId(int id) {

        this.id = id;

    }

    public String getName() {

        return name;

    }

    public void setName(String name) {

        this.name = name;

    }

    public String getAge() {

        return age;

    }

    public void setAge(String age) {

        this.age = age;

    }

    public Date getBirthDay() {

        return birthDay;

    }

    public void setBirthDay(Date birthDay) {

        this.birthDay = birthDay;

    }

    public List getList() {

        return list;

    }

    public void setList(List list) {

        this.list = list;

    }

    public Set getSet() {

        return set;

    }

    public void setSet(Set set) {

        this.set = set;

    }

    public Map getMap() {

        return map;

    }

    public void setMap(Map map) {

        this.map = map;

    }

    @Override

    public String toString() {

        return "Student [id=" + id + ", name=" + name + ", age=" + age

                + ", birthDay=" + birthDay + ", list=" + list + ", set=" + set

                + ", map=" + map + "]";

    }

}

2.3 java对象序列化成json对象时，处理日期的处理类

package json;

import java.text.SimpleDateFormat;

import java.util.Date;

import net.sf.json.JsonConfig;

import net.sf.json.processors.JsonValueProcessor;

/**

 *

 * @author yangguojun

 * java实体类转jsonObject时,日期处理类

 */

public class JsonDateValueProcessor implements JsonValueProcessor {

     /**

      * 集合中实体类日期处理

      */

    @Override

    public Object processArrayValue(Object value , JsonConfig config) {

        // TODO Auto-generated method stub

        return processor(value);

    }

    /**

     * 当个实体类日期处理

     */

    @Override

    public Object processObjectValue(String propertyName, Object value, JsonConfig config) {

        return processor(value);

    }

    /**

     * 把日期对象转为字符串

     * @param value

     * @return

     */

    private Object processor(Object value){

        SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");

        if(value instanceof Date){

            return format.format(value);

        }

        return value == null ? "":value.toString();

    }

}

2.4 测试类

package json;

import java.util.ArrayList;

import java.util.Date;

import java.util.HashMap;

import java.util.HashSet;

import net.sf.json.JSON;

import net.sf.json.JSONArray;

import net.sf.json.JSONObject;

import net.sf.json.JsonConfig;

public class JsonDemo {

    public static void main(String[] args) {

        //创建JSON对象的第一种方法

        JSONObject jsonObj1 = new JSONObject();

        jsonObj1.put("id", "1");

        jsonObj1.put("name", "rose");

        jsonObj1.put("age", 25);

        System.out.println("jsonObj1"+jsonObj1);

        //创建JSON对象的第二种方法

        HashMap<String, Object> map = new HashMap<String,Object>();

        map.put("id", "2");

        map.put("name", "zhangsan");

        map.put("age", "25");

        JSONObject jsonObj2 = JSONObject.fromObject(map);

        System.out.println("jsonObj2"+jsonObj2);

         //创建一个JsonArray方法1

        JSONArray jsonArray = new JSONArray();

        jsonArray.add(0, "ZHULI");

        jsonArray.add(1, "30");

        jsonArray.add(2, "ALI");

        System.out.println("jsonArray1：" + jsonArray);

        //创建JsonArray方法2

        ArrayList<String> arrayList = new ArrayList<String>();

        arrayList.add("柯文修");

        arrayList.add("23");

        arrayList.add("5");

        System.out.println("jsonArray2：" + JSONArray.fromObject(arrayList));

        //创建一个复杂JSON对象（JSON对象里有JSON数组）

        JSONObject jsonObj3 = new JSONObject();

        jsonObj3.put("id", 3);

        jsonObj3.put("name", "lisi");

        jsonObj3.put("age", 23);

        jsonObj3.put("arrayList", arrayList);

        System.out.println("jsonObj3"+jsonObj3);

        //创建一个复杂JSON数组(JSON数组里含有JSON对象)、

        JSONArray jsonArray3 = new JSONArray();

        jsonArray3.add("4");

        jsonArray3.add("wangwu");

        jsonArray3.add("26");

        jsonArray3.add(map);

        System.out.println("jsonArray3"+jsonArray3);

        //把JSON字符串转为JSON对象

        String jsonString = "{\"id\":3,\"name\":\"lisi\",\"age\":23,\"arrayList\":[\"ZHULI\",\"30\",\"ALI\"]}";

        JSONObject jsonObj4 = JSONObject.fromObject(jsonString);

        System.out.println(jsonObj4.get("id")+"--"+jsonObj4.get("name")+"--"+jsonObj4.get("age")+

                "--"+jsonObj4.get("arrayList"));

        //java实体类转为JSONObject

        Student stu = new Student();

        stu.setId(1);

        stu.setName("罗志茂");

        stu.setAge("23");

        stu.setBirthDay(new Date());

        stu.setList(arrayList);

        HashSet<Object> set = new HashSet<>();

        set.add("6");

        set.add("戚广辉");

        set.add("25");

        stu.setSet(set);

        stu.setMap(map);

        JsonConfig jsonConfig = new JsonConfig();

        jsonConfig.registerJsonValueProcessor(Date.class, new JsonDateValueProcessor());

        JSONObject jsonObj5 = JSONObject.fromObject(stu,jsonConfig);

        System.out.println("序列化:"+jsonObj5);

        //json转java实体类

        Student student = (Student) JSONObject.toBean(jsonObj5, Student.class);

        System.out.println("反序列化:"+student);

       }

}

2.5 测试结果

jsonObj1{"id":"1","name":"rose","age":25}
jsonObj2{"id":"2","age":"25","name":"zhangsan"}
jsonArray1：["ZHULI","30","ALI"]
jsonArray2：["柯文修","23","5"]
jsonObj3{"id":3,"name":"lisi","age":23,"arrayList":["柯文修","23","5"]}
jsonArray3["4","wangwu","26",{"id":"2","age":"25","name":"zhangsan"}]
3--lisi--23--["ZHULI","30","ALI"]
序列化:{"age":"23","birthDay":"2016-08-13 23:22:27","id":1,"list":["柯文修","23","5"],"map":{"id":"2","age":"25","name":"zhangsan"},"name":"罗志茂","set": ["戚广辉","6","25"]}
反序列化:Student [id=1, name=罗志茂, age=23, birthDay=Sat Aug 13 23:22:27 CST 2016, list=[柯文修, 23, 5], set=[戚广辉, 6, 25], map={id=2, name=zhangsan, age=25}]