Example usage for javax.persistence.criteria CriteriaQuery select

List of usage examples for javax.persistence.criteria CriteriaQuery select

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Introduction

In this page you can find the example usage for javax.persistence.criteria CriteriaQuery select.

Prototype

CriteriaQuery<T> select(Selection<? extends T> selection);

Source Link

Document

Specify the item that is to be returned in the query result.

Usage

From source file:org.broadleafcommerce.cms.admin.server.handler.PageItemCriteriaCustomPersistenceHandler.java

@Override
public Entity update(PersistencePackage persistencePackage, DynamicEntityDao dynamicEntityDao,
        RecordHelper helper) throws ServiceException {
    Entity entity = persistencePackage.getEntity();
    removeHtmlEncoding(entity);//from w ww  .  j  ava2  s.  c  om
    try {
        PersistencePerspective persistencePerspective = persistencePackage.getPersistencePerspective();
        Map<String, FieldMetadata> adminProperties = helper
                .getSimpleMergedProperties(PageItemCriteria.class.getName(), persistencePerspective);
        Object primaryKey = helper.getPrimaryKey(entity, adminProperties);
        PageItemCriteria adminInstance = (PageItemCriteria) dynamicEntityDao
                .retrieve(Class.forName(entity.getType()[0]), primaryKey);
        if (adminInstance.getPage().getLockedFlag()) {
            /*
            This may be an attempt to delete a target item criteria off an otherwise un-edited, production StructuredContent instance
             */
            CriteriaBuilder criteriaBuilder = dynamicEntityDao.getStandardEntityManager().getCriteriaBuilder();
            CriteriaQuery<Page> query = criteriaBuilder.createQuery(Page.class);
            Root<PageImpl> root = query.from(PageImpl.class);
            query.where(criteriaBuilder.and(criteriaBuilder.equal(root.get("archivedFlag"), Boolean.FALSE),
                    criteriaBuilder.equal(root.get("originalPageId"), adminInstance.getPage().getId())));
            query.select(root);
            TypedQuery<Page> scQuery = dynamicEntityDao.getStandardEntityManager().createQuery(query);
            try {
                checkCriteria: {
                    Page myContent = scQuery.getSingleResult();
                    for (PageItemCriteria itemCriteria : myContent.getQualifyingItemCriteria()) {
                        if (itemCriteria.getOrderItemMatchRule().equals(adminInstance.getOrderItemMatchRule())
                                && itemCriteria.getQuantity().equals(adminInstance.getQuantity())) {
                            //manually set the values - otherwise unwanted properties will be set
                            itemCriteria.setOrderItemMatchRule(
                                    entity.findProperty("orderItemMatchRule").getValue());
                            itemCriteria
                                    .setQuantity(Integer.parseInt(entity.findProperty("quantity").getValue()));
                            adminInstance = itemCriteria;
                            break checkCriteria;
                        }
                    }
                    throw new RuntimeException("Unable to find an item criteria to update");
                }
            } catch (Exception e) {
                throw new IllegalArgumentException("Unable to update a locked record");
            }
        } else {
            adminInstance = (PageItemCriteria) helper.createPopulatedInstance(adminInstance, entity,
                    adminProperties, false);
        }
        adminInstance = (PageItemCriteria) dynamicEntityDao.merge(adminInstance);
        Entity adminEntity = helper.getRecord(adminProperties, adminInstance, null, null);

        return adminEntity;
    } catch (Exception e) {
        LOG.error("Unable to execute persistence activity", e);
        throw new ServiceException("Unable to update entity for " + entity.getType()[0], e);
    }
}

From source file:com.sfs.captor.controller.RequirementAction.java

/**
 * find tests associated with this artifact
 *//*  w  w w .java 2 s  .co  m*/
private List<RequirementRuleTest> findRequirementRuleTests(RequirementRule requirementRule) {
    CriteriaBuilder cb = em.getCriteriaBuilder();
    CriteriaQuery<RequirementRuleTest> c = cb.createQuery(RequirementRuleTest.class);
    Root<RequirementRuleTest> obj = c.from(RequirementRuleTest.class);
    c.select(obj).where(cb.equal(obj.get("requirementRule"), requirementRule));
    return em.createQuery(c).getResultList();
}

From source file:com.sishuok.es.common.repository.support.SimpleBaseRepository.java

/**
 * Creates a {@link javax.persistence.TypedQuery} for the given {@link org.springframework.data.jpa.domain.Specification} and {@link org.springframework.data.domain.Sort}.
 *
 * @param spec can be {@literal null}./*from ww  w  .  ja  v  a  2 s.  c o m*/
 * @param sort can be {@literal null}.
 * @return
 */
private TypedQuery<M> getQuery(Specification<M> spec, Sort sort) {

    CriteriaBuilder builder = em.getCriteriaBuilder();
    CriteriaQuery<M> query = builder.createQuery(entityClass);

    Root<M> root = applySpecificationToCriteria(spec, query);
    query.select(root);

    applyJoins(root);

    if (sort != null) {
        query.orderBy(toOrders(sort, root, builder));
    }

    TypedQuery<M> q = em.createQuery(query);

    repositoryHelper.applyEnableQueryCache(q);

    return applyLockMode(q);
}

From source file:net.shopxx.dao.impl.OrderDaoImpl.java

public Page<Order> findPage(Order.Type type, Order.Status status, Member member, Goods goods,
        Boolean isPendingReceive, Boolean isPendingRefunds, Boolean isUseCouponCode, Boolean isExchangePoint,
        Boolean isAllocatedStock, Boolean hasExpired, Pageable pageable) {
    CriteriaBuilder criteriaBuilder = entityManager.getCriteriaBuilder();
    CriteriaQuery<Order> criteriaQuery = criteriaBuilder.createQuery(Order.class);
    Root<Order> root = criteriaQuery.from(Order.class);
    criteriaQuery.select(root);
    Predicate restrictions = criteriaBuilder.conjunction();
    if (type != null) {
        restrictions = criteriaBuilder.and(restrictions, criteriaBuilder.equal(root.get("type"), type));
    }//from   w  w  w .  java 2 s. c  o m
    if (status != null) {
        restrictions = criteriaBuilder.and(restrictions, criteriaBuilder.equal(root.get("status"), status));
    }
    if (member != null) {
        restrictions = criteriaBuilder.and(restrictions, criteriaBuilder.equal(root.get("member"), member));
    }
    if (goods != null) {
        Subquery<Product> productSubquery = criteriaQuery.subquery(Product.class);
        Root<Product> productSubqueryRoot = productSubquery.from(Product.class);
        productSubquery.select(productSubqueryRoot);
        productSubquery.where(criteriaBuilder.equal(productSubqueryRoot.get("goods"), goods));

        Subquery<OrderItem> orderItemSubquery = criteriaQuery.subquery(OrderItem.class);
        Root<OrderItem> orderItemSubqueryRoot = orderItemSubquery.from(OrderItem.class);
        orderItemSubquery.select(orderItemSubqueryRoot);
        orderItemSubquery.where(criteriaBuilder.equal(orderItemSubqueryRoot.get("order"), root),
                criteriaBuilder.in(orderItemSubqueryRoot.get("product")).value(productSubquery));
        restrictions = criteriaBuilder.and(restrictions, criteriaBuilder.exists(orderItemSubquery));
    }
    if (isPendingReceive != null) {
        Predicate predicate = criteriaBuilder.and(
                criteriaBuilder.or(root.get("expire").isNull(),
                        criteriaBuilder.greaterThan(root.<Date>get("expire"), new Date())),
                criteriaBuilder.equal(root.get("paymentMethodType"), PaymentMethod.Type.cashOnDelivery),
                criteriaBuilder.notEqual(root.get("status"), Order.Status.completed),
                criteriaBuilder.notEqual(root.get("status"), Order.Status.failed),
                criteriaBuilder.notEqual(root.get("status"), Order.Status.canceled),
                criteriaBuilder.notEqual(root.get("status"), Order.Status.denied),
                criteriaBuilder.lessThan(root.<BigDecimal>get("amountPaid"), root.<BigDecimal>get("amount")));
        if (isPendingReceive) {
            restrictions = criteriaBuilder.and(restrictions, predicate);
        } else {
            restrictions = criteriaBuilder.and(restrictions, criteriaBuilder.not(predicate));
        }
    }
    if (isPendingRefunds != null) {
        Predicate predicate = criteriaBuilder.or(
                criteriaBuilder.and(
                        criteriaBuilder.or(
                                criteriaBuilder.and(root.get("expire").isNotNull(),
                                        criteriaBuilder.lessThanOrEqualTo(root.<Date>get("expire"),
                                                new Date())),
                                criteriaBuilder.equal(root.get("status"), Order.Status.failed),
                                criteriaBuilder.equal(root.get("status"), Order.Status.canceled),
                                criteriaBuilder.equal(root.get("status"), Order.Status.denied)),
                        criteriaBuilder.greaterThan(root.<BigDecimal>get("amountPaid"), BigDecimal.ZERO)),
                criteriaBuilder.and(criteriaBuilder.equal(root.get("status"), Order.Status.completed),
                        criteriaBuilder.greaterThan(root.<BigDecimal>get("amountPaid"),
                                root.<BigDecimal>get("amount"))));
        if (isPendingRefunds) {
            restrictions = criteriaBuilder.and(restrictions, predicate);
        } else {
            restrictions = criteriaBuilder.and(restrictions, criteriaBuilder.not(predicate));
        }
    }
    if (isUseCouponCode != null) {
        restrictions = criteriaBuilder.and(restrictions,
                criteriaBuilder.equal(root.get("isUseCouponCode"), isUseCouponCode));
    }
    if (isExchangePoint != null) {
        restrictions = criteriaBuilder.and(restrictions,
                criteriaBuilder.equal(root.get("isExchangePoint"), isExchangePoint));
    }
    if (isAllocatedStock != null) {
        restrictions = criteriaBuilder.and(restrictions,
                criteriaBuilder.equal(root.get("isAllocatedStock"), isAllocatedStock));
    }
    if (hasExpired != null) {
        if (hasExpired) {
            restrictions = criteriaBuilder.and(restrictions, root.get("expire").isNotNull(),
                    criteriaBuilder.lessThanOrEqualTo(root.<Date>get("expire"), new Date()));
        } else {
            restrictions = criteriaBuilder.and(restrictions, criteriaBuilder.or(root.get("expire").isNull(),
                    criteriaBuilder.greaterThan(root.<Date>get("expire"), new Date())));
        }
    }
    criteriaQuery.where(restrictions);
    return super.findPage(criteriaQuery, pageable);
}

From source file:net.shopxx.dao.impl.OrderDaoImpl.java

public Long count(Order.Type type, Order.Status status, Member member, Goods goods, Boolean isPendingReceive,
        Boolean isPendingRefunds, Boolean isUseCouponCode, Boolean isExchangePoint, Boolean isAllocatedStock,
        Boolean hasExpired) {/*  www .j a v  a 2s.c o  m*/
    CriteriaBuilder criteriaBuilder = entityManager.getCriteriaBuilder();
    CriteriaQuery<Order> criteriaQuery = criteriaBuilder.createQuery(Order.class);
    Root<Order> root = criteriaQuery.from(Order.class);
    criteriaQuery.select(root);
    Predicate restrictions = criteriaBuilder.conjunction();
    if (type != null) {
        restrictions = criteriaBuilder.and(restrictions, criteriaBuilder.equal(root.get("type"), type));
    }
    if (status != null) {
        restrictions = criteriaBuilder.and(restrictions, criteriaBuilder.equal(root.get("status"), status));
    }
    if (member != null) {
        restrictions = criteriaBuilder.and(restrictions, criteriaBuilder.equal(root.get("member"), member));
    }
    if (goods != null) {
        Subquery<Product> productSubquery = criteriaQuery.subquery(Product.class);
        Root<Product> productSubqueryRoot = productSubquery.from(Product.class);
        productSubquery.select(productSubqueryRoot);
        productSubquery.where(criteriaBuilder.equal(productSubqueryRoot.get("goods"), goods));

        Subquery<OrderItem> orderItemSubquery = criteriaQuery.subquery(OrderItem.class);
        Root<OrderItem> orderItemSubqueryRoot = orderItemSubquery.from(OrderItem.class);
        orderItemSubquery.select(orderItemSubqueryRoot);
        orderItemSubquery.where(criteriaBuilder.equal(orderItemSubqueryRoot.get("order"), root),
                criteriaBuilder.in(orderItemSubqueryRoot.get("product")).value(productSubquery));
        restrictions = criteriaBuilder.and(restrictions, criteriaBuilder.exists(orderItemSubquery));
    }
    if (isPendingReceive != null) {
        Predicate predicate = criteriaBuilder.and(
                criteriaBuilder.or(root.get("expire").isNull(),
                        criteriaBuilder.greaterThan(root.<Date>get("expire"), new Date())),
                criteriaBuilder.equal(root.get("paymentMethodType"), PaymentMethod.Type.cashOnDelivery),
                criteriaBuilder.notEqual(root.get("status"), Order.Status.completed),
                criteriaBuilder.notEqual(root.get("status"), Order.Status.failed),
                criteriaBuilder.notEqual(root.get("status"), Order.Status.canceled),
                criteriaBuilder.notEqual(root.get("status"), Order.Status.denied),
                criteriaBuilder.lessThan(root.<BigDecimal>get("amountPaid"), root.<BigDecimal>get("amount")));
        if (isPendingReceive) {
            restrictions = criteriaBuilder.and(restrictions, predicate);
        } else {
            restrictions = criteriaBuilder.and(restrictions, criteriaBuilder.not(predicate));
        }
    }
    if (isPendingRefunds != null) {
        Predicate predicate = criteriaBuilder.or(
                criteriaBuilder.and(
                        criteriaBuilder.or(
                                criteriaBuilder.and(root.get("expire").isNotNull(),
                                        criteriaBuilder.lessThanOrEqualTo(root.<Date>get("expire"),
                                                new Date())),
                                criteriaBuilder.equal(root.get("status"), Order.Status.failed),
                                criteriaBuilder.equal(root.get("status"), Order.Status.canceled),
                                criteriaBuilder.equal(root.get("status"), Order.Status.denied)),
                        criteriaBuilder.greaterThan(root.<BigDecimal>get("amountPaid"), BigDecimal.ZERO)),
                criteriaBuilder.and(criteriaBuilder.equal(root.get("status"), Order.Status.completed),
                        criteriaBuilder.greaterThan(root.<BigDecimal>get("amountPaid"),
                                root.<BigDecimal>get("amount"))));
        if (isPendingRefunds) {
            restrictions = criteriaBuilder.and(restrictions, predicate);
        } else {
            restrictions = criteriaBuilder.and(restrictions, criteriaBuilder.not(predicate));
        }
    }
    if (isUseCouponCode != null) {
        restrictions = criteriaBuilder.and(restrictions,
                criteriaBuilder.equal(root.get("isUseCouponCode"), isUseCouponCode));
    }
    if (isExchangePoint != null) {
        restrictions = criteriaBuilder.and(restrictions,
                criteriaBuilder.equal(root.get("isExchangePoint"), isExchangePoint));
    }
    if (isAllocatedStock != null) {
        restrictions = criteriaBuilder.and(restrictions,
                criteriaBuilder.equal(root.get("isAllocatedStock"), isAllocatedStock));
    }
    if (hasExpired != null) {
        if (hasExpired) {
            restrictions = criteriaBuilder.and(restrictions, root.get("expire").isNotNull(),
                    criteriaBuilder.lessThanOrEqualTo(root.<Date>get("expire"), new Date()));
        } else {
            restrictions = criteriaBuilder.and(restrictions, criteriaBuilder.or(root.get("expire").isNull(),
                    criteriaBuilder.greaterThan(root.<Date>get("expire"), new Date())));
        }
    }
    criteriaQuery.where(restrictions);
    return super.count(criteriaQuery, null);
}

From source file:org.eclipse.jubula.client.core.persistence.NodePM.java

/**
 * Loads a bag of Nodes into the given session and returns the loaded
 * Nodes.//ww w  . j av a 2s . c om
 * 
 * @param projectId The Project in which to search for the Nodes.
 * @param guids The GUIDs for which to load Nodes.
 * @param session The session into which to load the Nodes.
 * @return the loaded Nodes, mapped by GUID. GUIDs for which no node could
 *         be found are mapped to <code>null</code>.
 */
@SuppressWarnings({ "unchecked", "rawtypes" })
public static synchronized Map<String, INodePO> getNodes(Long projectId, Collection<String> guids,
        EntityManager session) {

    CriteriaQuery query = session.getCriteriaBuilder().createQuery();
    Root from = query.from(NodeMaker.getNodePOClass());
    Predicate parentProjectPred = session.getCriteriaBuilder().equal(from.get("hbmParentProjectId"), projectId); //$NON-NLS-1$
    Predicate guidDisjunction = PersistenceUtil.getExpressionDisjunction(guids, from.get("guid"), //$NON-NLS-1$
            session.getCriteriaBuilder());
    query.select(from).where(parentProjectPred, guidDisjunction);

    List<INodePO> nodeList = session.createQuery(query).getResultList();

    Map<String, INodePO> guidToNodeMap = new HashMap<String, INodePO>();
    for (INodePO node : nodeList) {
        String guid = node.getGuid();
        if (!guidToNodeMap.containsKey(guid)) {
            guidToNodeMap.put(guid, node);
        }
    }

    return guidToNodeMap;
}

From source file:com.luna.common.repository.support.SimpleBaseRepository.java

/**
 * Creates a {@link javax.persistence.TypedQuery} for the given {@link org.springframework.data.jpa.domain.Specification} and {@link org.springframework.data.domain.Sort}.
 *
 * @param spec can be {@literal null}.//from  w  w  w.java2  s  .c  om
 * @param sort can be {@literal null}.
 * @return
 */
protected TypedQuery<M> getQuery(Specification<M> spec, Sort sort) {

    CriteriaBuilder builder = em.getCriteriaBuilder();
    CriteriaQuery<M> query = builder.createQuery(entityClass);

    Root<M> root = applySpecificationToCriteria(spec, query);
    query.select(root);

    applyJoins(root);

    if (sort != null) {
        query.orderBy(toOrders(sort, root, builder));
    }

    TypedQuery<M> q = em.createQuery(query);

    repositoryHelper.applyEnableQueryCache(q);

    return applyLockMode(q);
}

From source file:net.shopxx.dao.impl.OrderDaoImpl.java

public List<Order> findList(Order.Type type, Order.Status status, Member member, Goods goods,
        Boolean isPendingReceive, Boolean isPendingRefunds, Boolean isUseCouponCode, Boolean isExchangePoint,
        Boolean isAllocatedStock, Boolean hasExpired, Integer count, List<Filter> filters,
        List<net.shopxx.Order> orders) {
    CriteriaBuilder criteriaBuilder = entityManager.getCriteriaBuilder();
    CriteriaQuery<Order> criteriaQuery = criteriaBuilder.createQuery(Order.class);
    Root<Order> root = criteriaQuery.from(Order.class);
    criteriaQuery.select(root);
    Predicate restrictions = criteriaBuilder.conjunction();
    if (type != null) {
        restrictions = criteriaBuilder.and(restrictions, criteriaBuilder.equal(root.get("type"), type));
    }/*from   w ww  .  j  a v a 2s .  c om*/
    if (status != null) {
        restrictions = criteriaBuilder.and(restrictions, criteriaBuilder.equal(root.get("status"), status));
    }
    if (member != null) {
        restrictions = criteriaBuilder.and(restrictions, criteriaBuilder.equal(root.get("member"), member));
    }
    if (goods != null) {
        Subquery<Product> productSubquery = criteriaQuery.subquery(Product.class);
        Root<Product> productSubqueryRoot = productSubquery.from(Product.class);
        productSubquery.select(productSubqueryRoot);
        productSubquery.where(criteriaBuilder.equal(productSubqueryRoot.get("goods"), goods));

        Subquery<OrderItem> orderItemSubquery = criteriaQuery.subquery(OrderItem.class);
        Root<OrderItem> orderItemSubqueryRoot = orderItemSubquery.from(OrderItem.class);
        orderItemSubquery.select(orderItemSubqueryRoot);
        orderItemSubquery.where(criteriaBuilder.equal(orderItemSubqueryRoot.get("order"), root),
                criteriaBuilder.in(orderItemSubqueryRoot.get("product")).value(productSubquery));
        restrictions = criteriaBuilder.and(restrictions, criteriaBuilder.exists(orderItemSubquery));
    }
    if (isPendingReceive != null) {
        Predicate predicate = criteriaBuilder.and(
                criteriaBuilder.or(root.get("expire").isNull(),
                        criteriaBuilder.greaterThan(root.<Date>get("expire"), new Date())),
                criteriaBuilder.equal(root.get("paymentMethodType"), PaymentMethod.Type.cashOnDelivery),
                criteriaBuilder.notEqual(root.get("status"), Order.Status.completed),
                criteriaBuilder.notEqual(root.get("status"), Order.Status.failed),
                criteriaBuilder.notEqual(root.get("status"), Order.Status.canceled),
                criteriaBuilder.notEqual(root.get("status"), Order.Status.denied),
                criteriaBuilder.lessThan(root.<BigDecimal>get("amountPaid"), root.<BigDecimal>get("amount")));
        if (isPendingReceive) {
            restrictions = criteriaBuilder.and(restrictions, predicate);
        } else {
            restrictions = criteriaBuilder.and(restrictions, criteriaBuilder.not(predicate));
        }
    }
    if (isPendingRefunds != null) {
        Predicate predicate = criteriaBuilder.or(
                criteriaBuilder.and(
                        criteriaBuilder.or(
                                criteriaBuilder.and(root.get("expire").isNotNull(),
                                        criteriaBuilder.lessThanOrEqualTo(root.<Date>get("expire"),
                                                new Date())),
                                criteriaBuilder.equal(root.get("status"), Order.Status.failed),
                                criteriaBuilder.equal(root.get("status"), Order.Status.canceled),
                                criteriaBuilder.equal(root.get("status"), Order.Status.denied)),
                        criteriaBuilder.greaterThan(root.<BigDecimal>get("amountPaid"), BigDecimal.ZERO)),
                criteriaBuilder.and(criteriaBuilder.equal(root.get("status"), Order.Status.completed),
                        criteriaBuilder.greaterThan(root.<BigDecimal>get("amountPaid"),
                                root.<BigDecimal>get("amount"))));
        if (isPendingRefunds) {
            restrictions = criteriaBuilder.and(restrictions, predicate);
        } else {
            restrictions = criteriaBuilder.and(restrictions, criteriaBuilder.not(predicate));
        }
    }
    if (isUseCouponCode != null) {
        restrictions = criteriaBuilder.and(restrictions,
                criteriaBuilder.equal(root.get("isUseCouponCode"), isUseCouponCode));
    }
    if (isExchangePoint != null) {
        restrictions = criteriaBuilder.and(restrictions,
                criteriaBuilder.equal(root.get("isExchangePoint"), isExchangePoint));
    }
    if (isAllocatedStock != null) {
        restrictions = criteriaBuilder.and(restrictions,
                criteriaBuilder.equal(root.get("isAllocatedStock"), isAllocatedStock));
    }
    if (hasExpired != null) {
        if (hasExpired) {
            restrictions = criteriaBuilder.and(restrictions, root.get("expire").isNotNull(),
                    criteriaBuilder.lessThanOrEqualTo(root.<Date>get("expire"), new Date()));
        } else {
            restrictions = criteriaBuilder.and(restrictions, criteriaBuilder.or(root.get("expire").isNull(),
                    criteriaBuilder.greaterThan(root.<Date>get("expire"), new Date())));
        }
    }
    criteriaQuery.where(restrictions);
    return super.findList(criteriaQuery, null, count, filters, orders);
}

From source file:org.exoplatform.social.addons.storage.dao.jpa.query.RelationshipQueryBuilder.java

public TypedQuery<Connection> buildFilter() {
    EntityManager em = EntityManagerHolder.get();
    CriteriaBuilder cb = em.getCriteriaBuilder();
    CriteriaQuery<Connection> criteria = cb.createQuery(Connection.class);
    Root<Connection> connection = criteria.from(Connection.class);
    Join<Connection, Profile> receiver = connection.join(Connection_.receiver);
    ////from  w  w w  . jav  a 2 s  .c  om
    CriteriaQuery<Connection> select = criteria.select(connection);
    select.where(buildPredicateFilter(cb, receiver, connection));
    select.orderBy(cb.asc(receiver.get(Profile_.fullName)));
    //
    TypedQuery<Connection> typedQuery = em.createQuery(select);
    if (this.limit > 0) {
        typedQuery.setFirstResult((int) offset);
        typedQuery.setMaxResults((int) limit);
    }
    //
    return typedQuery;
}

From source file:eu.uqasar.service.dataadapter.JiraDataService.java

/**
 * Get the latest date of measurement snapshots
 * @return/*from ww w .j  ava  2 s .c o m*/
 */
public Date getLatestDate() {
    logger.info("Get the latest date from JIRA measurements...");
    CriteriaBuilder cb = em.getCriteriaBuilder();
    CriteriaQuery<JiraMetricMeasurement> query = cb.createQuery(JiraMetricMeasurement.class);
    Root<JiraMetricMeasurement> root = query.from(JiraMetricMeasurement.class);
    query.select(root);
    query.orderBy(cb.desc(root.get(JiraMetricMeasurement_.timeStamp)));
    Date latest;
    try {
        JiraMetricMeasurement m = em.createQuery(query).setMaxResults(1).getSingleResult();
        latest = m.getTimeStamp();
    } catch (NoResultException nre) {
        latest = null;
    }
    return latest;
}