前臺form表單傳file

@PostMapping("/dealAdd")
	public BaseRes dealAdd(HttpServletRequest request,
			@RequestParam("warningDealId") Long warningDealId,
            @RequestParam("description") String description
            /*@RequestParam("file") MultipartFile file*/
            ) {
		BaseRes res = new BaseRes(0);
		MultipartFile file= null;
        boolean isMultipart = ServletFileUpload.isMultipartContent(request);
        if (isMultipart){ 
            MultipartHttpServletRequest multipartRequest = WebUtils.getNativeRequest(request, MultipartHttpServletRequest.class);
            file = multipartRequest.getFile("file");
        }
		warningdealService.dealAdd(request,warningDealId,description,file);
		return res;
	}

$("#form").validate({
		rules:{
			name:{
				required:true,
				maxlength:16
			},
			time:{
				required:true,
			},
		},
		onkeyup:false,
		focusCleanup:true,
		success:"valid",
		submitHandler:function(form){
			var formData = new FormData();
			formData.append("file",$('#file')[0].files[0]);
		    formData.append("description", $('#description').val().trim());
		    formData.append("warningDealId",warningDealId);
			//$(form).ajaxSubmit();
			$('#submit').addClass('disabled')
			
			$.ajax({
				url:'../../warningDeal/dealAdd',
				type: 'post',
				data:formData,
				 processData:false,
		         contentType:false,
				success: function(res){
					if(res.code == 0){
						/* parent.table.ajax.reload(); */
						parent.location.reload();
						var index = parent.layer.getFrameIndex(window.name);
						parent.layer.close(index);
						
					} else {
						$('#submit').removeClass('disabled')
						layer.alert(res.message,{icon:2})
					}
				},
				error: function(XMLHttpRequest, textStatus, errorThrown) {
					$('#submit').removeClass('disabled')
					layer.alert(textStatus,{icon:2});
				}
			})
		}
	});

<form action="" method="post" class="form form-horizontal" id="form">
	

		<div class="row cl">
			<label class="form-label col-xs-4 col-sm-2">處理說明(督辦要求)：</label>
			<div class="formControls col-xs-8 col-sm-9">
				<textarea name="description" id="description"  class="textarea" style="width: 560px;"  ></textarea>
			</div>
			
		</div>
		<div class="row cl">
			<label class="form-label col-xs-4 col-sm-2">上傳附件：</label>
			<div class="formControls col-xs-8 col-sm-9">
				<!-- <textarea name="description" id="description"  class="textarea" style="width: 560px;"  ></textarea> -->
				<input type="file" id="file" name="file">
			</div>
			
		</div>
		<div class="row cl">
			<div class="col-xs-8 col-sm-9 col-xs-offset-4 col-sm-offset-2">
				<input class="btn btn-primary radius" id="submit" type="submit" value="&nbsp;&nbsp;確定&nbsp;&nbsp;">
				<button type="button" class="btn btn-default radius" onclick="layer_close();">&nbsp;&nbsp;取消&nbsp;&nbsp;</button>
			</div>
		</div>
	</form>