实现文件下载

response实现文件下载

String path =this.getServletContext().getRealPath("/download/美女.jpg");
            String filename = path.substring(path.lastIndexOf("\\")+1);
            //如果下载文件是中文，则文件名需要经过url编码
        //  response.setHeader("content-disposition", "attachment;filename=" + (filename));
            response.setHeader("content-disposition", "attachment;filename=" + URLEncoder.encode(filename,"UTF-8"));

            InputStream in =null;
            OutputStream out = null;
            try {


            in = new FileInputStream(path);
            int len = 0;
            byte buffer[] = new byte[1024];

            out =response.getOutputStream();
            while ((len=in.read(buffer))>0) {
                out.write(buffer,0,len);
                }
            }finally{
                if (in !=null) {
                    in.close();
                }
                if (out !=null) {
                    out.close();
                }
            }