java的有关问题

import java.util.regex.Matcher;
import java.util.regex.Pattern;
import java.net.*;
import java.io.*;

class ReadURL
{
public static void main(String[] args)
{
try//
{
// Define a URL
URL sourceURL = new URL(
"http://www.baidu.com/");//zupo.zju.edu.cn/

// Get a character input stream for the URL
BufferedReader in = new BufferedReader(
new InputStreamReader(
sourceURL.openStream()));

// Create the stream for the output file
PrintWriter out = new PrintWriter(
new BufferedWriter(
new FileWriter(
new File("Output_demo.htm"))));

System.out.println("Reading the file " + sourceURL.getFile() +
" on the host " + sourceURL.getHost() +
" using " + sourceURL.getProtocol()+
"\nURL: "+sourceURL);

// Read