程序员最基本的素养是什么？关闭流！

/**
     * 从浏览器下载压缩文件
     * @param file
     * @param response
     * @param isDelete
     * @throws IOException 
     */
    public static void downloadZipFile(File file,HttpServletResponse response,boolean isDelete) throws IOException{
    	BufferedInputStream fis = null;
    	OutputStream toClient = null;
		InputStream inputStream = null;
    	 try {
            
             // 清空response
             response.reset();
             toClient = new BufferedOutputStream(response.getOutputStream());
             response.setContentType("application/vnd.openxmlformats-officedocument.spreadsheetml.sheet;charset=UTF-8");
	           
             response.setHeader("Content-Disposition", "attachment;filename=" + URLEncoder.encode(file.getName(),"UTF-8"));
			 inputStream=new FileInputStream(file);
			 int len=0;
			 byte[] buffer=new byte[1024];
			 while((len=inputStream.read(buffer))>0){
				 toClient.write(buffer,0,len);
			 }
             toClient.flush();
          catch (IOException ex) {
              logger.error(ex.getMessage());
         }finally{
        	 if(fis!=null){
        		 fis.close();
        	 }
        	 if(toClient!= null){
        		 toClient.close();
        	 }
			 if(inputStream!= null){
				 inputStream.close();
			 }

         }
    	 //在所有流都关闭后再删除文件
        if(isDelete) {//是否将生成的服务器端文件删除
            if (file.exists()) {
                if (!file.delete()){
                    logger.error("删除失败");
                }
            }

        }
	}