客户端下载文件核心代码

/**
	 * 从服务器下载文件到客户端
	 * @param filezPath文件在服务器段的路径
	 * @param response
	 * @param filename文件名
	 */
	public void download(String filePath, HttpServletResponse response, String filename){
		try {
			response.setHeader("Content-disposition", "attachment;filename="+URLEncoder.encode(filename,"utf-8"));
		} catch (UnsupportedEncodingException e1) {
			// TODO Auto-generated catch block
			e1.printStackTrace();
		}
		try {
			InputStream in=new FileInputStream(filePath);
			OutputStream out=response.getOutputStream();
			byte[] buffer=new byte[1024*8];
			int length=0;
			while((length=in.read(buffer, 0, 1024*8))!=-1){
				out.write(buffer, 0, length);
			}
			out.flush();
			in.close();
		} catch (FileNotFoundException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}		
	}

需要注意的是，不要在Action层进行转向否则会出错。