import jakarta.validation.Valid;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.validation.BindingResult;
import org.springframework.validation.FieldError;
import org.springframework.web.bind.annotation.*;

Why if I send a negative age or a blank name the @Valid annotation doesn’t work and the person saves to database?

There is the following JSON that is sent to the server.

{
    "name": "",
    "age": -30
}

@Entity Person :

@Id
    @Column(name = "id")
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private int id;

    @Column(name = "name")
    @NotEmpty(message = "Name mustn't be empty!")
    @Size(min = 2, max = 20, message = "Name must be between 2 and 20 characters long!")
    private String name;

    @Column(name = "age")
    @Min(value = 1, message = "Age must be greater than 0!")
    private int age;

Controller method:

@PostMapping
    public ResponseEntity<HttpStatus> create(@RequestBody @Valid Person person, BindingResult bindingResult) {
        if (bindingResult.hasErrors()) {
            StringBuilder errorMsg = new StringBuilder();

            List<FieldError> errors = bindingResult.getFieldErrors();
            for (FieldError error : errors) {
                errorMsg.append(error.getField()).append(" - ").append(error.getDefaultMessage()).append(";");
            }

            throw new PersonNotCreatedException(errorMsg.toString());
        }

        personService.savePerson(person);

        return ResponseEntity.ok(HttpStatus.OK);
    }

org.springframework.validation.BeanPropertyBindingResult: 0 errors