JSONObject与JSONArray的使用

参考文献:

http://blog.csdn.net/huangwuyi/article/details/5412500

1.JAR包简介

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:

  1. commons-lang.jar
  2. commons-beanutils.jar
  3. commons-collections.jar
  4. commons-logging.jar 
  5. ezmorph.jar
  6. json-lib-2.2.2-jdk15.jar

2.JSONObject对象使用

JSON-lib包是一个beans,collections,maps,java arrays 和XML和JSON互相转换的包。在本例中,我们将使用JSONObject类创建JSONObject对象,然后我们打印这些对象的值。为了使用JSONObject对象,我们要引入"net.sf.json"包。为了给对象添加元素,我们要使用put()方法。

2.1.实例1

 

package jsontest;

import net.sf.json.JSONArray;
import net.sf.json.JSONObject;

public class JSONObjectSample {

// 创建JSONObject对象
private static JSONObject createJSONObject() {
JSONObject jsonObject = new JSONObject();
jsonObject.put("username", "huangwuyi");
jsonObject.put("sex", "男");
jsonObject.put("QQ", "413425430");
jsonObject.put("Min.score", new Integer(99));
jsonObject.put("nickname", "梦中心境");
return jsonObject;
}

public static void main(String[] args) {
JSONObject jsonObject = JSONObjectSample.createJSONObject();//静待方法,直接通过类名+方法调用
// 输出jsonobject对象
System.out.println("jsonObject:" + jsonObject);

// 判读输出对象的类型
boolean isArray = jsonObject.isArray();
boolean isEmpty = jsonObject.isEmpty();
boolean isNullObject = jsonObject.isNullObject();
System.out.println("是否为数组:" + isArray + ", 是否为空:" + isEmpty
+ ", isNullObject:" + isNullObject);

// 添加属性,在jsonObject后面追加元素。
jsonObject.element("address", "福建省厦门市");
System.out.println("添加属性后的对象:" + jsonObject);

// 返回一个JSONArray对象
JSONArray jsonArray = new JSONArray();
jsonArray.add(0, "this is a jsonArray value");
jsonArray.add(1, "another jsonArray value");
jsonObject.element("jsonArray", jsonArray);
//在jsonObject后面住家一个jsonArray
JSONArray array = jsonObject.getJSONArray("jsonArray");
System.out.println(jsonObject);


System.out.println("返回一个JSONArray对象:" + array);
// 添加JSONArray后的值
// {"username":"huangwuyi","sex":"男","QQ":"413425430","Min.score":99,"nickname":"梦中心境","address":"福建省厦门市","jsonArray":["this is a jsonArray value","another jsonArray value"]}
System.out.println("结果=" + jsonObject);

// 根据key返回一个字符串
String username = jsonObject.getString("username");
System.out.println("username==>" + username);

// 把字符转换为 JSONObject
String temp = jsonObject.toString();
JSONObject object = JSONObject.fromObject(temp);
// 转换后根据Key返回值
System.out.println("qq=" + object.get("QQ"));

}

}

输出结果

jsonObject:{"username":"huangwuyi","sex":"男","QQ":"413425430","Min.score":99,"nickname":"梦中心境"}
是否为数组:false, 是否为空:false, isNullObject:false
添加属性后的对象:{"username":"huangwuyi","sex":"男","QQ":"413425430","Min.score":99,"nickname":"梦中心境","address":"福建省厦门市"}
{"username":"huangwuyi","sex":"男","QQ":"413425430","Min.score":99,"nickname":"梦中心境","address":"福建省厦门市","jsonArray":["this is a jsonArray value","another jsonArray value"]}
返回一个JSONArray对象:["this is a jsonArray value","another jsonArray value"]
结果={"username":"huangwuyi","sex":"男","QQ":"413425430","Min.score":99,"nickname":"梦中心境","address":"福建省厦门市","jsonArray":["this is a jsonArray value","another jsonArray value"]}
username==>huangwuyi
qq=413425430

2.2.实例2.

package jsontest;

import net.sf.json.JSONArray;
import net.sf.json.JSONObject;

public class JSONTest {
public static void main(String args[])
{
JSONObject jsonObj0 = new JSONObject();
JSONObject jsonObj = new JSONObject();
JSONObject jsonObj2 = new JSONObject();
JSONObject jsonObj3 = new JSONObject();
JSONArray jsonArray = new JSONArray();

//创建jsonObj0
jsonObj0.put("name0", "zhangsan");
jsonObj0.put("sex1", "female");
System.out.println("jsonObj0:"+jsonObj0);

//创建jsonObj1
jsonObj.put("name", "xuwei");
jsonObj.put("sex", "male");
System.out.println("jsonObj:"+jsonObj);

//创建jsonObj2,包含两个条目,条目内容分别为jsonObj0,jsonObj1
jsonObj2.put("item0", jsonObj0);
jsonObj2.put("item1", jsonObj);
System.out.println("jsonObj2:"+jsonObj2);

//创建jsonObj3,只有一个条目,内容为jsonObj2
jsonObj3.element("j3", jsonObj2);
System.out.println("jsonObj3:"+jsonObj3);

//往JSONArray中添加JSONObject对象。发现JSONArray跟JSONObject的区别就是JSONArray比JSONObject多中括号[]
jsonArray.add(jsonObj);
System.out.println("jsonArray:"+jsonArray);

JSONObject jsonObj4 = new JSONObject();
jsonObj4.element("weather", jsonArray);
System.out.println("jsonObj4:"+jsonObj4);
}
}

输出结果:

jsonObj0:{"name0":"zhangsan","sex1":"female"}
jsonObj:{"name":"xuwei","sex":"male"}
jsonObj2:{"item0":{"name0":"zhangsan","sex1":"female"},"item1":{"name":"xuwei","sex":"male"}}
jsonObj3:{"j3":{"item0":{"name0":"zhangsan","sex1":"female"},"item1":{"name":"xuwei","sex":"male"}}}
jsonArray:[{"name":"xuwei","sex":"male"}]
jsonObj4:{"weather":[{"name":"xuwei","sex":"male"}]}





posted @ 2011-12-16 16:50 xwdreamer 阅读(...) 评论(...) 编辑 收藏