使用Spring boot中的注释验证POJO中的嵌套JSON

public class User {
    @NotBlank(message = "用户名不能为空")
    private String username;

    @Valid
    private Address address;

    // 省略getter和setter方法
}

public class Address {
    @NotBlank(message = "街道不能为空")
    private String street;

    @NotBlank(message = "城市不能为空")
    private String city;

    // 省略getter和setter方法
}

@RestController
public class UserController {

    @PostMapping("/users")
    public ResponseEntity<?> createUser(@Valid @RequestBody User user, BindingResult result) {
        if (result.hasErrors()) {
            // 处理验证失败的情况
            List<String> errorMessages = result.getAllErrors().stream()
                    .map(DefaultMessageSourceResolvable::getDefaultMessage)
                    .collect(Collectors.toList());

            return ResponseEntity.badRequest().body(errorMessages);
        }

        // 处理验证成功的情况
        // ...

        return ResponseEntity.ok().build();
    }
}