java代码发送JSON格式的httpPOST请求

<pre name="code" class="java">package com.test;

import Java.io.BufferedReader;
import java.io.DataOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.UnsupportedEncodingException;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import net.sf.json.JSONObject;

public class AppAddTest {

public static final String ADD_URL = "www.2cto.com";

public static void appadd() {

    try {
        //创建连接
        URL url = new URL(ADD_URL);
        HttpURLConnection connection = (HttpURLConnection) url
                .openConnection();
        connection.setDoOutput(true);
        connection.setDoInput(true);
        connection.setRequestMethod("POST");
        connection.setUseCaches(false);
        connection.setInstanceFollowRedirects(true);
    //application/x-javascript text/xml->xml数据 application/x-javascript->json对象 application/x-www-form-urlencoded->表单数据 application/json;charset=utf-8 -> json数据
        connection.setRequestProperty("Content-Type",
                "application/x-www-form-urlencoded");
    connection.setRequestProperty("accept", "*/*");
        connection.setRequestProperty("user-agent",
                "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)");

        connection.connect();

        //POST请求
        DataOutputStream out = new DataOutputStream(
                connection.getOutputStream());
        JSONObject obj = new JSONObject();
        obj.element("app_name", "asdf");
        obj.element("app_ip", "10.21.243.234");
        obj.element("app_port", 8080);
        obj.element("app_type", "001");
        obj.element("app_area", "asd");

        out.writeBytes(obj.toString());
        out.flush();
        out.close();

        //读取响应
        BufferedReader reader = new BufferedReader(new InputStreamReader(
                connection.getInputStream()));
        String lines;
        StringBuffer sb = new StringBuffer("");
        while ((lines = reader.readLine()) != null) {
            lines = new String(lines.getBytes(), "utf-8");
            sb.append(lines);
        }
        System.out.println(sb);
        reader.close();
        // 断开连接
        connection.disconnect();
    } catch (MalformedURLException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } catch (UnsupportedEncodingException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }

}

public static void main(String[] args) {
    appadd();
}

}