用Java实现HTTP文件队列下载

import java.io.*;import java.net.*;import java.util.*;/** * <p>Title: 个人开发的API</p> * <p>Description: 将指定的HTTP网络资源在本地以文件形式存放</p> * <p>Copyright: Copyright (c) 2004</p> * <p>Company: NewSky</p> * @author MagicLiao * @version 1.0 */public class HttpGet {  public final static boolean DEBUG = true;//调试用  private static int BUFFER_SIZE = 8096;//缓冲区大小  private Vector vDownLoad = new Vector();//URL列表  private Vector vFileList = new Vector();//下载后的保存文件名列表  /**   * 构造方法   */  public HttpGet() {  }  /**   * 清除下载列表   */  public void resetList() {    vDownLoad.clear();    vFileList.clear();  }  /**   * 增加下载列表项   *   * @param url String   * @param filename String   */  public void addItem(String url, String filename) {    vDownLoad.add(url);    vFileList.add(filename);  }  /**   * 根据列表下载资源   */  public void downLoadByList() {    String url = null;    String filename = null;        //按列表顺序保存资源    for (int i = 0; i < vDownLoad.size(); i++) {      url = (String) vDownLoad.get(i);      filename = (String) vFileList.get(i);      try {        saveToFile(url, filename);      }      catch (IOException err) {        if (DEBUG) {          System.out.println("资源[" + url + "]下载失败!!!");        }      }    }    if (DEBUG) {      System.out.println("下载完成!!!");    }  }  /**   * 将HTTP资源另存为文件   *   * @param destUrl String   * @param fileName String   * @throws Exception   */  public void saveToFile(String destUrl, String fileName) throws IOException {    FileOutputStream fos = null;    BufferedInputStream bis = null;    HttpURLConnection httpUrl = null;    URL url = null;    byte[] buf = new byte[BUFFER_SIZE];    int size = 0;        //建立链接    url = new URL(destUrl);    httpUrl = (HttpURLConnection) url.openConnection();    //连接指定的资源    httpUrl.connect();    //获取网络输入流    bis = new BufferedInputStream(httpUrl.getInputStream());    //建立文件    fos = new FileOutputStream(fileName);    if (this.DEBUG) System.out.println("正在获取链接[" + destUrl + "]的内容...\n将其保存为文件[" + fileName + "]");    //保存文件    while ( (size = bis.read(buf)) != -1)       fos.write(buf, 0, size);        fos.close();    bis.close();    httpUrl.disconnect();  }  /**   * 设置代理服务器   *   * @param proxy String   * @param proxyPort String   */  public void setProxyServer(String proxy, String proxyPort) {    //设置代理服务器    System.getProperties().put("proxySet", "true");    System.getProperties().put("proxyHost", proxy);    System.getProperties().put("proxyPort", proxyPort);  }  /**   * 设置认证用户名与密码   *   * @param uid String   * @param pwd String   */  public void setAuthenticator(String uid, String pwd) {    Authenticator.setDefault(new MyAuthenticator(uid, pwd));  }  /**   * 主方法(用于测试)   *   * @param argv String[]   */  public static void main(String argv[]) {    HttpGet oInstance = new HttpGet();try {//增加下载列表（此处用户可以写入自己代码来增加下载列表）oInstance.addItem("http://www.ebook.com/java/网络编程001.zip","./网络编程1.zip");oInstance.addItem("http://www.ebook.com/java/网络编程002.zip","./网络编程2.zip");oInstance.addItem("http://www.ebook.com/java/网络编程003.zip","./网络编程3.zip");oInstance.addItem("http://www.ebook.com/java/网络编程004.zip","./网络编程4.zip");oInstance.addItem("http://www.ebook.com/java/网络编程005.zip","./网络编程5.zip");oInstance.addItem("http://www.ebook.com/java/网络编程006.zip","./网络编程6.zip");oInstance.addItem("http://www.ebook.com/java/网络编程007.zip","./网络编程7.zip");//开始下载oInstance.downLoadByList();    }    catch (Exception err) {      System.out.println(err.getMessage());    }  }}