Java学习笔记：JSONObject与JSONArray的使用

Java不像PHP解析和生产JSON总是一个比较痛苦的过程。但是使用JSONObject和JSONArray会让整个过程相对舒服一些。

需要依赖的包：commons-lang.jar commons-beanutils.jar commons-collections.jar commons-logging.jar ezmorph.jar json-lib-2.2.2-jdk15.jar

1. 创建一个JSONObject对象：

package .video.resource.controller.web;

import java.util.ArrayList;

import java.util.HashMap;

import net.sf.json.JSONArray;

import net.sf.json.JSONObject;

public class Test {

public static void main(String[] args) {

//JsonObject和JsonArray区别就是JsonObject是对象形式，JsonArray是数组形式 //创建JsonObject第一种方法

JSONObject jsonObject = new JSONObject();

jsonObject.put("UserName", "ZHULI");

jsonObject.put("age", "30");

jsonObject.put("workIn", "ALI");

System.out.println("jsonObject1：" + jsonObject);

//创建JsonObject第二种方法

HashMap hashMap = new HashMap();

hashMap.put("UserName", "ZHULI");

hashMap.put("age", "30");

hashMap.put("workIn", "ALI");

System.out.println("jsonObject2：" + JSONObject.fromObject(hashMap));

//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 arrayList = new ArrayList();

arrayList.add("ZHULI");

arrayList.add("30");

arrayList.add("ALI");

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

//如果JSONArray解析一个HashMap，则会将整个对象的放进一个数组的值中

System.out.println("jsonArray FROM HASHMAP：" +

JSONArray.fromObject(hashMap));

//组装一个复杂的JSONArray

JSONObject jsonObject2 = new JSONObject();

jsonObject2.put("UserName", "ZHULI");

jsonObject2.put("age", "30");

jsonObject2.put("workIn", "ALI");

jsonObject2.element("Array", arrayList);

System.out.println("jsonObject2：" + jsonObject2);

}

}

结果：

jsonObject1：{"UserName":"ZHULI","age":"30","workIn":"ALI"}

jsonObject2：{"workIn":"ALI","age":"30","UserName":"ZHULI"}

jsonArray1：["ZHULI","30","ALI"]

jsonArray2：["ZHULI","30","ALI"]

jsonArray FROM HASHMAP：[{"workIn":"ALI","age":"30","UserName":"ZHULI"}] jsonObject2：{"UserName":"ZHULI","age":"30","workIn":"ALI","Array":["ZHULI","30","ALI"]}

解析JSON字符串：

package .video.resource.controller.web;

import net.sf.json.JSONArray;

import net.sf.json.JSONObject;

public class Test {

public static void main(String[] args) {

String jsonString =

"{\"UserName\":\"ZHULI\",\"age\":\"30\",\"workIn\":\"ALI\",\"Array\":[\"ZHULI\",\"3 0\",\"ALI\"]}";

//将Json字符串转为java对象

JSONObject obj = JSONObject.fromObject(jsonString);

//获取Object中的UserName

if (obj.has("UserName")) {

System.out.println("UserName:" + obj.getString("UserName"));

}

//获取ArrayObject

if (obj.has("Array")) {

JSONArray transitListArray = obj.getJSONArray("Array");

for (int i = 0; i < transitListArray.size(); i++) {

System.out.print("Array:" + transitListArray.getString(i) + " "); }

}

}

}

返回：

UserName:ZHULI

Array:ZHULI Array:30 Array:ALI