Java文件下載代碼

public  static  void DownLoadFile (String filePath, String fileName,

                  HttpServletResponse response)  throws  Exception {

            System. out .println( "filepath:"  + filePath);

            File file =  new  File(filePath);

             if  (!file.exists()) {

                  System. out .println( "文件不存在" );

            }  else  {

                  FileInputStream fis =  new  FileInputStream(file);

                  BufferedInputStream bis =  new  BufferedInputStream(fis);

 

                  OutputStream os = response.getOutputStream();

                  BufferedOutputStream bos =  new  BufferedOutputStream(os);

 

                  fileName = URLEncoder.encode(fileName,  "UTF-8" );

                  fileName =  new  String(fileName.getBytes( "UTF-8" ),  "GBK" );

 

                  response.reset();

                  response.setContentType( "UTF-8" );

                  response.setContentType( "Application/x-msdownload" );

                  response.setHeader( "Content-Disposition" ,  "attachment;filename="

                              + fileName);

                  response.setHeader( "Content-Length" , String

                              .valueOf(bis.available()));

 

                   int  bytesRead = 0;

                   byte [] buffer =  new  byte [1024];

                   while  ((bytesRead = bis.read(buffer)) != -1) {

                        bos.write(buffer, 0, bytesRead);

                  }

                  bos.flush();

                  bos.close();

                  bis.close();

 

                  os.close();

                  fis.close();

            }

      }