java實現文件下載

文件下載

輸出內容包含 

1.文件內容：content

2. 輸出類型 contentType : application/msword

3 文件長度: contentLength： content.length

4.文件名稱:

    /** 
         * 下載文件 
         * @param request 
         * @param response 
         * @throws IOException 
         * @throws InterruptedException 
         */  
        public void downloadDoc(HttpServletRequest request,HttpServletResponse response) throws IOException, InterruptedException  
        {  
            String id=request.getParameter("id")==null?"0":request.getParameter("id");  
            DocumentAtt documentAtt=documentAttDao.findById(id); //業務對象根據實際情況修改  
            byte [] content=documentAtt.getFiles();  
            OutputStream os=response.getOutputStream();  
            InputStream is=new  ByteArrayInputStream(content);   
            response.setContentType(documentAtt.getFiletype());//<span style="font-family: Arial, Helvetica, sans-serif;">可不設置</span>  
            response.setContentLength(content.length);//可不設置  
            response.setHeader("Content-Disposition","attachment;filename="+new String(documentAtt.getName().getBytes("GBK"),"ISO-8859-1"));  
            byte[] buffer = new byte[4000];  
            int length;  
            while((length = is.read(buffer)) != -1){  
                  os.write(buffer,0,length);  
            }  

            is.close();  
            os.close();  
        }