文件下载

public HttpServletResponse download(String path, HttpServletResponse response) {  
       try {  
           // path是指欲下载的文件的路径。  
           File file = new File(path);  
           // 取得文件名。  
           String filename = file.getName();  
           // 取得文件的后缀名。  
           String ext = filename.substring(filename.lastIndexOf(".") + 1).toUpperCase();  
 
           // 以流的形式下载文件。  
           InputStream fis = new BufferedInputStream(new FileInputStream(path));  
           byte[] buffer = new byte[fis.available()];  
           fis.read(buffer);  
           fis.close();  
           // 清空response  
           response.reset();  
           // 设置response的Header  
           response.addHeader("Content-Disposition", "attachment;filename=" + new String(filename.getBytes()));  
           response.addHeader("Content-Length", "" + file.length());  
           OutputStream toClient = new BufferedOutputStream(response.getOutputStream());  
           response.setContentType("application/octet-stream");  
           toClient.write(buffer);  
           toClient.flush();  
           toClient.close();  
       } catch (IOException ex) {  
           ex.printStackTrace();  
       }  
       return response;  
   }  
 
   public void downloadLocal(HttpServletResponse response) throws FileNotFoundException {  
       // 下载本地文件  
       String fileName = "Operator.doc".toString(); // 文件的默认保存名  
       // 读到流中  
       InputStream inStream = new FileInputStream("d:/xiaobai.doc");// 文件的存放路径  
       // 设置输出的格式  
       response.reset();  
       response.setContentType("bin");  
       response.addHeader("Content-Disposition", "attachment; filename=\"" + fileName + "\"");  
       // 循环取出流中的数据  
       byte[] b = new byte[100];  
       int len;  
       try {  
           while ((len = inStream.read(b)) > 0)  
               response.getOutputStream().write(b, 0, len);  
           inStream.close();  
       } catch (IOException e) {  
           e.printStackTrace();  
       }  
   }  
 
   public void downloadNet(HttpServletResponse response) throws MalformedURLException {  
       // 下载网络文件  
       int bytesum = 0;  
       int byteread = 0;  
 
       URL url = new URL("windine.blogdriver.com/logo.gif");  
 
       try {  
           URLConnection conn = url.openConnection();  
           InputStream inStream = conn.getInputStream();  
           FileOutputStream fs = new FileOutputStream("d:/abc.gif");  
 
           byte[] buffer = new byte[1204];  
           int length;  
           while ((byteread = inStream.read(buffer)) != -1) {  
               bytesum += byteread;  
               System.out.println(bytesum);  
               fs.write(buffer, 0, byteread);  
           }  
       } catch (FileNotFoundException e) {  
           e.printStackTrace();  
       } catch (IOException e) {  
           e.printStackTrace();  
       }  
   }