validation-api参数校验

<dependency>
    <groupId>javax.validation</groupId>
    <artifactId>validation-api</artifactId>
</dependency>

@PostMapping("/test.do")
public JSONMessageResponse test(@Validated @RequestBody TestVO testVO) {
   
}

public class TestVO {
    @NotEmpty(message = "名称不能为空")
    String name;		// 名称

    @ListNotEmptyNull(message = "不能为空的数组")   // 自定义
    @ListSize(min = 1, max = 5, message = "错误的数组大小")
    @Valid
    List<UserVO> list;
}

public class UserVO {
    @NotEmpty(message = "名称不能为空")
    String name;		// 名称
}

@ControllerAdvice
public class GlobalExceptionHandler extends ResponseEntityExceptionHandler {
    
    @Override
    protected ResponseEntity<Object> handleMethodArgumentNotValid(MethodArgumentNotValidException ex, HttpHeaders headers, HttpStatus status, WebRequest request) {
        BindingResult bindingResult = ex.getBindingResult();
        String errorMessage = "参数校验失败";

        for (FieldError fieldError : bindingResult.getFieldErrors()) {
            errorMessage += ", " + fieldError.getDefaultMessage();
        }
        JSONMessageResponse error = SystemResultUtil.error(5006, errorMessage);
        return new ResponseEntity<>(error, HttpStatus.BAD_REQUEST);
    }
}

{
  "code": 5006,
  "message": "参数校验失败,名称不能为空", 
  "status": 1 
}

/**
 * 指定列表的大小
 *
 * @author sky.javaweb@qq.com
 * @version 1.0
 * @date 2019-01-07
 */
@Target({ANNOTATION_TYPE, METHOD, FIELD})
@Retention(RUNTIME)
@Documented
@Constraint(validatedBy = ListSizeValidationImpl.class)此处指定了注解的实现类为ListSizeValidationImpl
public @interface ListSize {
    int min() default 0;

    int max() default Integer.MAX_VALUE;

    String message() default "List集合大小错误";

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

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

    /**
     * 定义List，为了让Bean的一个属性上可以添加多套规则
     */
    @Target({METHOD, FIELD, ANNOTATION_TYPE, CONSTRUCTOR, PARAMETER})
    @Retention(RUNTIME)
    @Documented
    @interface List {
        ListSize[] value();
    }

}

/**
 * @author sky.javaweb@qq.com
 * @version 1.0
 * @date 2019-01-07
 */
@Service
public class ListSizeValidationImpl implements ConstraintValidator<ListSize, List> {

    private int min;
    private int max;

    @Override
    public void initialize(ListSize constraintAnnotation) {
        this.min = constraintAnnotation.min();
        this.max = constraintAnnotation.max();
    }

    @Override
    public boolean isValid(List list, ConstraintValidatorContext context) {
        if (list != null) {
            if (list.size() < min || list.size() > max) {
                return false;
            }
        }
        return true;
    }
}

    @ListSize(min = 2, max = 5, message = "无效的案例图片")
    List<String> imageList;     // 图片

{
  "code": 5006,
  "message": "参数校验失败, 无效的案例图片",
  "status": 1
}