Example usage for javax.persistence.criteria Join alias

Introduction

In this page you can find the example usage for javax.persistence.criteria Join alias.

Prototype

Selection<X> alias(String name);

Source Link

Document

Assigns an alias to the selection item.

Usage

From source file:org.jdal.dao.jpa.JpaUtils.java

/**
 * Copy Joins// ww  w.j a  v  a2 s  .c  o  m
 * @param from source Join
 * @param to destination Join
 */
public static void copyJoins(From<?, ?> from, From<?, ?> to) {
    for (Join<?, ?> j : from.getJoins()) {
        Join<?, ?> toJoin = to.join(j.getAttribute().getName(), j.getJoinType());
        toJoin.alias(getOrCreateAlias(j));

        copyJoins(j, toJoin);
    }

    for (Fetch<?, ?> f : from.getFetches()) {
        Fetch<?, ?> toFetch = to.fetch(f.getAttribute().getName());
        copyFetches(f, toFetch);

    }
}

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From source file:com.zero.dao.impl.BaseDaoImpl.java

private void copyJoins(From<?, ?> from, From<?, ?> to) {
    for (Join<?, ?> join : from.getJoins()) {
        Join<?, ?> toJoin = to.join(join.getAttribute().getName(), join.getJoinType());
        toJoin.alias(getAlias(join));
        copyJoins(join, toJoin);//w  ww  .ja v  a  2 s. c  o  m
    }
    for (Fetch<?, ?> fetch : from.getFetches()) {
        Fetch<?, ?> toFetch = to.fetch(fetch.getAttribute().getName());
        copyFetches(fetch, toFetch);
    }
}

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From source file:cn.buk.hotel.dao.HotelDaoImpl.java

@Override
public List<HotelInfo> searchAvailableHotel(HotelSearchCriteria sc) {

    List<HotelInfo> hotelInfos = null;

    try {/*from   ww  w.j  a  v a  2s. c o m*/
        //body
        CriteriaBuilder cb = getEm().getCriteriaBuilder();

        CriteriaQuery<HotelInfo> cq = cb.createQuery(HotelInfo.class);
        Root<HotelInfo> root = cq.from(HotelInfo.class);
        root.alias("h");

        List<Predicate> predicates = new ArrayList<Predicate>();

        Predicate predicate = cb.equal(root.get(HotelInfo_.cityId), sc.getCityId());
        predicates.add(predicate);

        /**
         * ratePlanStatus-1???)  yfddai 2015-1-8
         */
        predicate = cb.notEqual(root.get(HotelInfo_.ratePlanStatus), -1);
        predicates.add(predicate);

        if (sc.getDistrictId() > 0) {
            predicate = cb.equal(root.get(HotelInfo_.areaId), sc.getDistrictId());
            predicates.add(predicate);
        }

        if (sc.getHotelName() != null && sc.getHotelName().trim().length() > 0) {
            predicate = cb.like(root.get(HotelInfo_.hotelName), "%" + sc.getHotelName() + "%");
            predicates.add(predicate);
        }

        if (sc.getStar() != null && sc.getStar().length() > 0) {
            Join<HotelInfo, HotelAward> hotelAward = root.join("hotelAwards", JoinType.LEFT);
            hotelAward.alias("ha");

            predicates.add(cb.equal(hotelAward.get("provider"), "HotelStarRate"));

            String[] stars = sc.getStar().split(",");
            Predicate p0 = cb.disjunction();
            for (String star : stars) {
                if (star.length() == 0)
                    continue;
                int starLevel = Integer.parseInt(star);
                if (starLevel == 2)
                    p0 = cb.or(p0, cb.le(hotelAward.get(HotelAward_.rating), starLevel));
                else
                    p0 = cb.or(p0, cb.equal(hotelAward.get("rating"), starLevel));
            }
            predicates.add(p0);
        }

        if (sc.getZoneId() > 0) {
            Join<HotelInfo, HotelAddressZone> hotelZone = root.join(HotelInfo_.hotelAddressZones,
                    JoinType.LEFT);
            hotelZone.alias("hz");

            predicate = cb.equal(hotelZone.get(HotelAddressZone_.zoneCode), sc.getZoneId());
            predicates.add(predicate);
        }

        // count items
        CriteriaQuery<Long> cq0 = cb.createQuery(Long.class);
        Root<HotelInfo> root0 = cq0.from(HotelInfo.class);
        root0.alias("h");
        if (sc.getStar() != null && sc.getStar().length() > 0) {
            Join<HotelInfo, HotelAward> hotelAward0 = root0.join("hotelAwards", JoinType.LEFT);
            hotelAward0.alias("ha");
        }
        if (sc.getZoneId() > 0) {
            Join<HotelInfo, HotelAddressZone> hotelZone0 = root0.join(HotelInfo_.hotelAddressZones,
                    JoinType.LEFT);
            hotelZone0.alias("hz");
        }
        cq0.select(cb.count(root0)).where(predicates.toArray(new Predicate[0]));
        Long count = getEm().createQuery(cq0).getSingleResult();

        sc.getPage().setRowCount(count.intValue());

        int firstPosition = (sc.getPage().getPageNo() - 1) * sc.getPage().getPageSize();
        cq.select(root).where(predicates.toArray(new Predicate[0]));

        hotelInfos = getEm().createQuery(cq).setFirstResult(firstPosition)
                .setMaxResults(sc.getPage().getPageSize()).getResultList();
    } catch (PersistenceException e) {
        logger.error(e.getMessage());
    }

    return hotelInfos == null ? new ArrayList<HotelInfo>() : hotelInfos;
}

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