java调用http，解析返回的xml

java文件

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.StringReader;
import java.net.HttpURLConnection;
import java.net.URL;

import org.jdom.Document;
import org.jdom.Element;
import org.jdom.input.SAXBuilder;
import org.xml.sax.InputSource;

public class HttpTest {
public static void main(String args[]){
URL url = null;
HttpURLConnection httpurlconnection = null;
try
{
url=new URL("http://localhost:8080/HttpTest?username=abc");

// 以post方式请求
httpurlconnection =(HttpURLConnection)url.openConnection();
httpurlconnection.setDoOutput(true);
httpurlconnection.setRequestMethod("POST");

// 获取响应代码
int code = httpurlconnection.getResponseCode();
System.out.println("code>>>>>>" +code);

// 获取页面内容
BufferedReader in = null;
StringBuffer sb = new StringBuffer();
in = new BufferedReader(new InputStreamReader(httpurlconnection
.getInputStream()));
String inputLine;
while ((inputLine = in.readLine()) != null) {
sb.append(inputLine);
}
System.out.println(sb.toString());

StringReader read = new StringReader(sb.toString());
InputSource source = new InputSource(read);
SAXBuilder sax = new SAXBuilder();

Document doc = sax.build(source);
Element root = doc.getRootElement();
System.out.println(root.getValue());
}
catch(Exception e){
e.printStackTrace();
}
finally{
if(httpurlconnection!=null)
httpurlconnection.disconnect();
}
}
}

访问的jsp文件

<%@ page language="java" pageEncoding="ISO-8859-1"%>
<%@ page contentType="text/html; charset=gb2312"%>
<%
String a = "" + request.getParameter("username");
response.setContentType("text/xml;charset=GBK");
out.println("<?xml version=/"1.0/" encoding=/"UTF-8/"?>");
out.println("<result>" + a + "</result>");
%>