MessageSpecs.java 文件源码

/**
 * Get a specification using the specified parameters.
 *
 * @param user The recipient's user
 * @param subject The subject of the message
 * @param text The text of the message
 * @return The specification
 */
public static Specification<MessageEntity> findReceivedMessagesForUser(
        final UserEntity user,
        @Nullable final String subject,
        @Nullable final String text
) {
    return (final Root<MessageEntity> root, final CriteriaQuery<?> cq, final CriteriaBuilder cb) -> {
        final List<Predicate> predicates = new ArrayList<>();

        predicates.add(cb.equal(root.get(MessageEntity_.recipient), user));

        if (Optional.ofNullable(subject).isPresent()) {
            predicates.add(cb.like(root.get(MessageEntity_.subject), "%" + subject + "%"));
        }
        if (Optional.ofNullable(text).isPresent()) {
            predicates.add(cb.like(root.get(MessageEntity_.text), "%" + text + "%"));
        }

        predicates.add(cb.isTrue(root.get(MessageEntity_.isVisibleForRecipient)));

        return cb.and(predicates.toArray(new Predicate[predicates.size()]));
    };
}