JavaWeb文件下载功能实例代码

public void downloadFile(File file, String downName, HttpServletRequest request, HttpServletResponse response) { OutputStream out = null; FileInputStream fin = null; BufferedInputStream bin = null; try {  if (file.exists()) {  String finalFileName = null;  String agent = request.getHeader("User-Agent");  boolean isMSIE = (agent != null && agent.indexOf("MSIE") != -1);  if (isMSIE) {   finalFileName = URLEncoder.encode(downName, "UTF8");  } else {   finalFileName = new String(downName.getBytes("UTF-8"), "ISO-8859-1");  }  response.setContentType("application/x-msdownload");  response.setHeader("Content-Disposition", "attachment; filename=".concat(finalFileName));  out = response.getOutputStream();  fin = new FileInputStream(file);  bin = new BufferedInputStream(fin);  for (int data = bin.read(); data > -1; data = bin.read()) {   out.write(data);  }  } else {  } } catch (Exception e) {  e.printStackTrace(); } finally {  try {  if (bin != null)   bin.close();  if (fin != null)   fin.close();  if (out != null)   out.close();  } catch (Exception e2) {  e2.printStackTrace();  } } }