文件附件下載

    /**
	 * 下載（傳附件的id下載附件，適合後臺多個附件上傳，前臺對應下載）
	 * @throws IOException
	 */
	@ResponseBody
	@RequestMapping(value="/font/annex/download",produces="text/plain;charset=UTF-8")
	public void downloadAnnexById(@RequestParam Integer id, Model model, HttpServletRequest request, HttpServletResponse response) throws IOException{
		List<Annex> annexList = null;
		annexList = annexService.queryAnnexListById(20, id);
		if(GeneralUtil.isNotNull(annexList) && annexList.size() > 0){
			Annex annex = annexList.get(0);
			if(annex.getPath() != null &&! annex.getPath().equals("")){
				//下載
				//設置文件MIME類型  
				String fileName = annex.getName();
				String filePath = annex.getPath();
				
				if (request.getHeader("User-Agent").toUpperCase().indexOf("MSIE") > 0) {  
				    fileName = URLEncoder.encode(fileName, "UTF-8");  
				} else {  
				    fileName = new String(fileName.getBytes("UTF-8"), "ISO8859-1");  
				} 
		        response.setContentType(request.getServletContext().getMimeType(fileName));  
		        //設置Content-Disposition  
		        response.setHeader("Content-Disposition", "attachment;filename="+fileName);  
		        //讀取目標文件，通過response將目標文件寫到客戶端  
		        //獲取目標文件的絕對路徑  
		        String fullFileName = request.getServletContext().getRealPath(filePath);  
		        File file = new File(fullFileName);
		        if(file.exists()){
		        	//讀取文件  
			        InputStream in = new FileInputStream(fullFileName);  
			        OutputStream out = response.getOutputStream();  
			          
			        //寫文件  
			        int b;  
			        while((b=in.read())!= -1)  
			        {  
			            out.write(b);  
			        }  
			          
			        in.close();  
			        out.close();  
		        }
		        
			}
		}
	}