如何获取ConstraintViolation

import javax.validation.ConstraintViolation;
import javax.validation.Validation;
import javax.validation.Validator;
import javax.validation.ValidatorFactory;
import java.util.Set;

public class ValidationExample {
    public static void main(String[] args) {
        // 创建验证器
        ValidatorFactory factory = Validation.buildDefaultValidatorFactory();
        Validator validator = factory.getValidator();

        // 准备需要验证的对象
        User user = new User();
        user.setUsername(null);
        user.setEmail("invalid_email");

        // 执行验证
        Set<ConstraintViolation<User>> violations = validator.validate(user);

        // 处理违反约束的情况
        for (ConstraintViolation<User> violation : violations) {
            System.out.println("违反约束: " + violation.getConstraintDescriptor().getAnnotation());
            System.out.println("属性名: " + violation.getPropertyPath().toString());
            System.out.println("无效的值: " + violation.getInvalidValue());
            System.out.println("错误消息: " + violation.getMessage());
            System.out.println("----------------------------------");
        }
    }
}