如何对ajax请求使用spring验证？

Question

现在我有以下控制器方法：

@ModelAttribute("multipartFileWrapper")
public MultipartFileWrapper createEmployeeModel() {
   return new MultipartFileWrapper();
}

public ResponseEntity<String> handleFileUpload(@Validated MultipartFileWrapper file, BindingResult result, Principal principal, HttpSession session) {
        ResponseEntity<String> responseEntity;

        if (result.hasErrors()) {
           ....

以及用于验证的bean包装器：

@Component
public class MultipartFileWrapper {
    @Extensions(imageFormats = {".jpg",".png",".gif",".bmp"}, videoFormats = {".mp4"})
    MultipartFile multipartFile;

    public MultipartFile getMultipartFile() {
        return multipartFile;
    }

    public void setMultipartFile(MultipartFile multipartFile) {
        this.multipartFile = multipartFile;
    }
}

扩展注释声明：

@Documented
@Retention(RUNTIME)
@Constraint(validatedBy = {ExtensionValidator.class})
@Target({ METHOD, FIELD, ANNOTATION_TYPE, CONSTRUCTOR, PARAMETER })
public @interface Extensions {

    String message() default "file format is not acceptable";

    Class<?>[] groups() default {};

    Class<? extends Payload>[] payload() default {};

    /**
     * Specify accepted content types.
     *
     * @return accepted extensions
     */
    String[] imageFormats();
    String[] videoFormats();
}

和验证者：

public class ExtensionValidator implements ConstraintValidator<Extensions, MultipartFile> {

    private String[] acceptedExtensions;

    @Override
    public void initialize(Extensions extensions) {
        //logic
    }

    @Override
    public boolean isValid(MultipartFile value, ConstraintValidatorContext context) {
        //logic
     }
}

并遵循jsp：

<form:form method="POST"  action="uploadImage" enctype="multipart/form-data" id="imageUploadForm" commandName="multipartFileWrapper" >
 ....
</form:form>

现在我需要验证使用ajax发送的文件。

ajax电话：

$(".file").on("change", function() {
        var data = $(this).attr('data');
        if (typeof data !== 'undefined' && data !== false) {
            var image=this.files[0];
            var terminalId=data.replace("file", "");
            var postData = new FormData();
            postData.append('image',image);
            postData.append('terminalId',terminalId);

            $("div[data='errors"+terminalId+"']").hide();
         $.ajax({
             url: "<c:url value='/owner/terminals/uploadImage'/>",
             type: 'POST',
             dataType: 'json',
             processData: false,
             contentType: false,
             data: postData
         })
         .success(function(data) {
            ...
          })
         .fail(function() {
                ...
              });


        } 

    });

我该怎么做？是否可以重用我当前的代码？