如何使用Spring Validation优雅地校验参数

public String add(UserVO userVO) {
 if(userVO.getAge() == null){
 return "年龄不能为空";
 }
 if(userVO.getAge() > 120){
 return "年龄不能超过120";
 }
 if(userVO.getName().isEmpty()){
 return "用户名不能为空";
 }
 // 省略一堆参数校验...
 return "OK";
}

<!--校验组件-->
<dependency>
 <groupId>org.springframework.boot</groupId>
 <artifactId>spring-boot-starter-validation</artifactId>
</dependency>
<!--web组件-->
<dependency>
 <groupId>org.springframework.boot</groupId>
 <artifactId>spring-boot-starter-web</artifactId>
</dependency>

public class UserVO {
 @NotNull(message = "age 不能为空")
 private Integer age;
}

public String add1(@Validated UserVO userVO, BindingResult result) {
 List<FieldError> fieldErrors = result.getFieldErrors();
 if(!fieldErrors.isEmpty()){
 return fieldErrors.get(0).getDefaultMessage();
 }
 return "OK";
}

public class ResultInfo<T>{
 private Integer status;
 private String message;
 private T response;
 // 省略其他代码...
}

public ResultInfo add2(@Validated UserVO userVO, BindingResult result) {
 List<FieldError> fieldErrors = result.getFieldErrors();
 List<String> collect = fieldErrors.stream()
  .map(o -> o.getDefaultMessage())
  .collect(Collectors.toList());
 return new ResultInfo<>().success(400,"请求参数错误",collect);
}

{
 "status": 400,
 "message": "请求参数错误",
 "response": [
 "年龄必须在[1,120]之间",
 "bg 字段的整数位最多为3位，小数位最多为1位",
 "name 不能为空",
 "email 格式错误"
 ]
}

@RestControllerAdvice
public class GlobalControllerAdvice {
 private static final String BAD_REQUEST_MSG = "客户端请求参数错误";
 // <1> 处理 form data方式调用接口校验失败抛出的异常 
 @ExceptionHandler(BindException.class)
 public ResultInfo bindExceptionHandler(BindException e) {
 List<FieldError> fieldErrors = e.getBindingResult().getFieldErrors();
 List<String> collect = fieldErrors.stream()
  .map(o -> o.getDefaultMessage())
  .collect(Collectors.toList());
 return new ResultInfo().success(HttpStatus.BAD_REQUEST.value(), BAD_REQUEST_MSG, collect);
 }
 // <2> 处理 json 请求体调用接口校验失败抛出的异常 
 @ExceptionHandler(MethodArgumentNotValidException.class)
 public ResultInfo methodArgumentNotValidExceptionHandler(MethodArgumentNotValidException e) {
 List<FieldError> fieldErrors = e.getBindingResult().getFieldErrors();
 List<String> collect = fieldErrors.stream()
  .map(o -> o.getDefaultMessage())
  .collect(Collectors.toList());
 return new ResultInfo().success(HttpStatus.BAD_REQUEST.value(), BAD_REQUEST_MSG, collect);
 }
 // <3> 处理单个参数校验失败抛出的异常
 @ExceptionHandler(ConstraintViolationException.class)
 public ResultInfo constraintViolationExceptionHandler(ConstraintViolationException e) {
 Set<ConstraintViolation<?>> constraintViolations = e.getConstraintViolations();
 List<String> collect = constraintViolations.stream()
  .map(o -> o.getMessage())
  .collect(Collectors.toList());
 return new ResultInfo().success(HttpStatus.BAD_REQUEST.value(), BAD_REQUEST_MSG, collect);
 }
 

}

public interface Update extends Default{
}

public class UserVO {
 @NotBlank(message = "name 不能为空",groups = Update.class)
 private String name;
 // 省略其他代码...
}

@PostMapping("update")
public ResultInfo update(@Validated({Update.class}) UserVO userVO) {
 return new ResultInfo().success(userVO);
}

/**
 * Default Jakarta Bean Validation group.
 * <p>
 * Unless a list of groups is explicitly defined:
 * <ul>
 * <li>constraints belong to the {@code Default} group</li>
 * <li>validation applies to the {@code Default} group</li>
 * </ul>
 * Most structural constraints should belong to the default group.
 *
 * @author Emmanuel Bernard
 */
public interface Default {
}

{
 "status": 400,
 "message": "客户端请求参数错误",
 "response": [
  "name 不能为空",
  "age 不能为空",
  "email 不能为空"
 ]
}

{
 "status": 400,
 "message": "客户端请求参数错误",
 "response": [
  "name 不能为空"
 ]
}

public class OrderVO {
 @NotNull
 private Long id;
 @NotBlank(message = "itemName 不能为空")
 private String itemName;
 // 省略其他代码...
}

public class UserVO {
 @NotBlank(message = "name 不能为空",groups = Update.class)
 private String name;
	//需要递归校验的OrderVO
 @Valid
 private OrderVO orderVO;
 // 省略其他代码...
} 

@Target({METHOD, FIELD, ANNOTATION_TYPE, CONSTRUCTOR, PARAMETER})
@Retention(RUNTIME)
@Documented
@Constraint(validatedBy = {HaveNoBlankValidator.class})// 标明由哪个类执行校验逻辑
public @interface HaveNoBlank {
	
 // 校验出错时默认返回的消息
 String message() default "字符串中不能含有空格";

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

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

 /**
  * 同一个元素上指定多个该注解时使用
  */
 @Target({ METHOD, FIELD, ANNOTATION_TYPE, CONSTRUCTOR, PARAMETER, TYPE_USE })
 @Retention(RUNTIME)
 @Documented
 public @interface List {
  NotBlank[] value();
 }
}

public class HaveNoBlankValidator implements ConstraintValidator<HaveNoBlank, String> {
 @Override
 public boolean isValid(String value, ConstraintValidatorContext context) {
  // null 不做检验
  if (value == null) {
   return true;
  }
  if (value.contains(" ")) {
   // 校验失败
   return false;
  }
  // 校验成功
  return true;
 }
}