SpringBoot校验前端传递的参数的流程步骤

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-validation</artifactId>
</dependency>

@PostMapping("/user")
public Result createUser(@Valid @RequestBody User user) { ... }

@RestController
@Validated // ← 关键！
public class UserController {
    @GetMapping("/user/{id}")
    public Result getUser(@Min(1) @PathVariable Long id) { ... }
}

@RestControllerAdvice
public class GlobalValidationExceptionHandler {

    // 处理 @RequestBody 校验失败
    @ExceptionHandler(MethodArgumentNotValidException.class)
    @ResponseStatus(HttpStatus.BAD_REQUEST)
    public ApiResult<Map<String, String>> handleRequestBody(
            MethodArgumentNotValidException ex) {
        Map<String, String> errors = new HashMap<>();
        ex.getBindingResult().getFieldErrors()
          .forEach(e -> errors.put(e.getField(), e.getDefaultMessage()));
        return ApiResult.error(400, "参数校验失败").data(errors);
    }

    // 处理 @RequestParam / @PathVariable 校验失败
    @ExceptionHandler(ConstraintViolationException.class)
    @ResponseStatus(HttpStatus.BAD_REQUEST)
    public ApiResult<Map<String, String>> handleParams(
            ConstraintViolationException ex) {
        Map<String, String> errors = new HashMap<>();
        ex.getConstraintViolations().forEach(v ->
            errors.put(v.getPropertyPath().toString(), v.getMessage()));
        return ApiResult.error(400, "参数校验失败").data(errors);
    }
}

{ "code": 400, "message": "参数校验失败", "data": { "name": "姓名不能为空" } }