springboot的实体类字段校验的分组校验具体实现步骤

// 新增时的校验分组
public interface CreateGroup {}
// 更新时的校验分组
public interface UpdateGroup {}

public class User {
    @NotBlank(message = "用户ID不能为空", groups = UpdateGroup.class)
    private String id;
    @NotBlank(message = "用户名不能为空", groups = CreateGroup.class)
    private String username;
    @Size(min = 6, max = 20, message = "密码长度需在6到20位之间", groups = {CreateGroup.class, UpdateGroup.class})
    private String password;
    // 省略Getter和Setter
}

@RestController
public class UserController {
    // 新增用户（校验 CreateGroup 分组）
    @PostMapping("/users")
    public String createUser(@Validated(CreateGroup.class) @RequestBody User user) {
        return "用户新增成功";
    }
    // 更新用户（校验 UpdateGroup 分组）
    @PutMapping("/users/{id}")
    public String updateUser(@Validated(UpdateGroup.class) @RequestBody User user) {
        return "用户更新成功";
    }
}

@RestControllerAdvice
public class GlobalExceptionHandler {
    @ResponseStatus(HttpStatus.BAD_REQUEST)
    @ExceptionHandler(ConstraintViolationException.class)
    public Map<String, Object> handleConstraintViolationException(ConstraintViolationException ex) {
        Map<String, String> errors = new HashMap<>();
        ex.getConstraintViolations().forEach(violation -> {
            String field = violation.getPropertyPath().toString();
            String message = violation.getMessage();
            errors.put(field, message);
        });
        return Map.of(
            "code", HttpStatus.BAD_REQUEST.value(),
            "message", "参数校验失败",
            "data", errors
        );
    }
}

POST /users
Content-Type: application/json
{
    "password": "12345"
}

{
    "code": 400,
    "message": "参数校验失败",
    "data": {
        "username": "用户名不能为空",
        "password": "密码长度需在6到20位之间"
    }
}

PUT /users/123
Content-Type: application/json
{
    "password": "12345"
}

{
    "code": 400,
    "message": "参数校验失败",
    "data": {
        "id": "用户ID不能为空",
        "password": "密码长度需在6到20位之间"
    }
}

@Validated({CreateGroup.class, AnotherGroup.class})

@Validated(value = {UpdateGroup.class, Default.class})

public interface AdvancedGroup extends CreateGroup {}