文件下载代码实现

 1 public void downLoad(String filePath, HttpServletResponse response, boolean isOnLine) throws Exception {
 2     File f = new File(filePath);
 3     if (!f.exists()) {
 4       response.sendError(404, "File not found!");
 5       return;
 6     }
 7     BufferedInputStream br = new BufferedInputStream(new FileInputStream(f));
 8     byte[] buf = new byte[1024];
 9     int len = 0;
10  
11     response.reset(); // 非常重要
12     if (isOnLine) { // 在线打开方式
13       URL u = new URL("file:///" + filePath);
14       response.setContentType(u.openConnection().getContentType());
15       response.setHeader("Content-Disposition", "inline; filename=" + f.getName());
16       // 文件名应该编码成UTF-8
17     } else { // 纯下载方式
18       response.setContentType("application/x-msdownload");
19       response.setHeader("Content-Disposition", "attachment; filename=" + f.getName());
20     }
21     OutputStream out = response.getOutputStream();
22     while ((len = br.read(buf)) > 0)
23       out.write(buf, 0, len);
24     br.close();
25     out.close();
26   }