javabean 校驗類

校驗工具類：
public class ValidationUtility {
    private static ValidatorFactory factory = Validation.buildDefaultValidatorFactory();
    private static Validator validator = factory.getValidator();

    public static <T> Set<ConstraintViolation<T>> validate(T obj, Class<?>... groups) {
        return validator.validate(obj, groups);
    }
}

如何使用：

Set<ConstraintViolation<People>> constraintViolations = ValidationUtility.validate(people);

constraintViolations 集合中存放對象people的一些錯誤信息。