java获得网页源代码

import java.io.BufferedReader;import java.io.FileOutputStream;import java.io.IOException;import java.io.InputStream;import java.io.InputStreamReader;import java.io.OutputStreamWriter;import java.io.PrintWriter;import java.net.URL;import java.net.URLConnection;public class Test {/** * @param args */public static void main(String[] args) {try { URL url = new URL("http://localhost:8080/webroot/login.do?method=begin"); URLConnection conn = url.openConnection(); conn.setDoOutput(true); InputStream in = null; in = url.openStream(); String content = pipe(in,"gbk");  System.out.println(content);  } catch (Exception e) {e.printStackTrace();}}static String pipe(InputStream in,String charset) throws IOException {        StringBuffer s = new StringBuffer();        if(charset==null||"".equals(charset)){        charset="gbk";        }        String rLine = null;        BufferedReader bReader = new BufferedReader(new InputStreamReader(in,charset));        PrintWriter pw = null;        FileOutputStream fo = new FileOutputStream("../index.html");OutputStreamWriter writer = new OutputStreamWriter(fo, "gbk");pw = new PrintWriter(writer);        while ( (rLine = bReader.readLine()) != null) {            String tmp_rLine = rLine;            int str_len = tmp_rLine.length();            if (str_len > 0) {              s.append(tmp_rLine);              pw.println(tmp_rLine);              pw.flush();            }            tmp_rLine = null;       }        in.close();        pw.close();        return s.toString();}}