httpClient download file(爬虫)

package com.opensource.httpclient.bfs;

import java.io.DataOutputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;

import org.apache.commons.httpclient.HttpStatus;
import org.apache.http.Header;
import org.apache.http.HttpResponse;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;

public class DownLoadFile
{
   
    public String getFileNameByUrl(String url, String contentType)
    {
        url = url.substring(7);
       
        if (contentType.indexOf("html") != -1)
        {
            url = url.replaceAll("[\?/:*|<>"]", "_") + ".html";
            return url;
        }
        else
        {
            return url.replaceAll("[\?/:*|<>"]", "_") + "." + contentType.substring(contentType.lastIndexOf("/") + 1);
        }
    }
   
    public void saveToLocal(byte[] data, String filePath)
    {
        try
        {
            DataOutputStream out = new DataOutputStream(new FileOutputStream(new File(filePath)));
            for (int i = 0; i < data.length; i++)
                out.write(data[i]);
            out.flush();
            out.close();
        }
        catch (IOException e)
        {
            e.printStackTrace();
        }
    }
   
    public String downloadFile(String url)
        throws ClientProtocolException, IOException
    {
        String filePath = null;
       
        HttpClient httpClient = new DefaultHttpClient();
       
        HttpGet get = new HttpGet(url);
       
        HttpResponse rsp = httpClient.execute(get);
       
        if (rsp.getStatusLine().getStatusCode() != HttpStatus.SC_OK)
        {
            System.err.println("Method failed: " + rsp.getStatusLine());
            filePath = null;
        }
        Header[] header = rsp.getHeaders("Content-Type");
        filePath = "D:\" + getFileNameByUrl(url, header[0].getValue());
       
        saveToLocal(rsp.toString().getBytes(), filePath);
       
        return filePath;
    }
   
    public static void main(String[] args)
        throws ClientProtocolException, IOException
    {
        DownLoadFile downLoadFile = new DownLoadFile();
       
        String temp = downLoadFile.downloadFile("http://www.huawei.com/cn/");
       
        System.out.println(temp);
    }
   
}