Java url下载

5. 代码清单

import java.io.*;
import java.net.*;
import java.util.*;

/**
* ＜p＞Description: 将指定的HTTP网络资源在本地以文件形式存放＜/p＞
**/
public class SaveFile {

    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 SaveFile() {}

    /**
     　* 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();
    }

    /**
        * 将HTTP资源另存为文件
        *
        * @param destUrl String
        * @param fileName String
        * @throws Exception
        */
       public void saveToFile2(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();
      
//           String authString = "username" + ":" + "password";
            String authString = "50301" + ":" + "88888888";
           String auth = "Basic " +
                         new sun.misc.BASE64Encoder().encode(authString.getBytes());
           httpUrl.setRequestProperty("Proxy-Authorization", auth);
      
//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);
    }

    public void setAuthenticator(String uid, String pwd) {
        Authenticator.setDefault(new MyAuthenticator());
    }

    /**
    * 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");
//     //开始下载
//     oInstance.downLoadByList();
     oInstance.saveToFile("http://www.ebook.com/java/网络编程001.zip", "./down.zip");
   }
    catch (Exception err) {
    System.out.println(err.getMessage());
    }
    }
}




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[1024];  
            int size = 0;  
              
            url = new URL(destUrl);  
            httpUrl = (HttpURLConnection) url.openConnection();  
            httpUrl.connect();  
            bis = new BufferedInputStream(httpUrl.getInputStream());  
            fos = new FileOutputStream(fileName);  
            while ((size = bis.read(buf)) != -1)  
                fos.write(buf, 0, size);  
            fos.close();  
            bis.close();  
            httpUrl.disconnect();  
        } 

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[1024];
        int size = 0;
       
        url = new URL(destUrl);
        httpUrl = (HttpURLConnection) url.openConnection();
        httpUrl.connect();
        bis = new BufferedInputStream(httpUrl.getInputStream());
        fos = new FileOutputStream(fileName);
        while ((size = bis.read(buf)) != -1)
            fos.write(buf, 0, size);
        fos.close();
        bis.close();
        httpUrl.disconnect();
    }


saveToFile("http://10.1.0.214:8080/SameTimeApp/data/sa.dat", "d:\\sa.dat");