小程序：Java下载单页HTML（可下载引用资源）

/*
 *****************************************************************************
 * This software is under the Apache License Version 2.0
 * Author: Tao -  mail:cn.java.river@gmail.com
 * Spreading Your Heart
 ****************************************************************************
 */

package atao.util.html;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileOutputStream;
import java.io.FileWriter;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.URL;

import org.apache.commons.lang.StringUtils;

/**
 * 
 * A Simple HTML downloader which can also download Page resources.
 * 

 * Note: This Tool won't download related or sub HTML
 * 
 * @author Tao
 * @since 1.0
 */
public class HtmlDownloader
{

    //URL will be downloaded.
    private static String url = "http://pervasive2.morselli.unimo.it/~nicola/courses/IngegneriaDelSoftware/java/J6d_xml.html";
    
    //workspace folder.
    private static String workspace = "download";
    
    //sub css and js resources sign 
    private static String urlSign = "
  





Note: don't use Java Character Writers,
     * otherwise you can't get pictures correctly.
     * 
     * @param subUrl
     */
    private static void downloadChild (String subUrl)
    {
        if (StringUtils.isNotEmpty (subUrl))
        {
            if (subUrl.startsWith ("http:"))
            {
                System.out.println ("subUrl not support yet.");
            }
            else
            {
                long start = System.nanoTime ();
                try
                {
                    String forUrl = subUrl.replace (" ", "%20");
                    if (!forUrl.startsWith ("/"))
                    {
                        forUrl = "/" + forUrl;
                    }
                    URL u = new URL (rootUrl + forUrl);
                    InputStream reader = u.openStream ();
                    File f = createDownloadFile (subUrl);
                    FileOutputStream writer = new FileOutputStream (f);
                    byte[] buff = new byte[1024];
                    int size = -1;
                    while ((size = reader.read (buff)) != -1)
                    {
                        writer.write (buff, 0, size);

                    }
                    reader.close ();
                    writer.close ();
                }
                catch (Exception e)
                {
                    e.printStackTrace ();
                }
                System.out.println ("Source:" + subUrl +"download time(s):" + String.format ("%.3f", (double)(System.nanoTime () - start)/ 1000000000.00));
            }
        }
        else
        {
            System.out.println ("subUrl is Empty.");

        }
    }

    /**
     * create sub file,create parent folders if necessary.
     * 
     * @param url related path of a url source.
     * @return created file.
     */
    private static File createDownloadFile (String url)
    {
        File f = new File (workspace, url);
        f.getParentFile ().mkdirs ();
        return f;
    }

}