Example usage for javax.persistence.criteria CriteriaBuilder createQuery

List of usage examples for javax.persistence.criteria CriteriaBuilder createQuery

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Introduction

In this page you can find the example usage for javax.persistence.criteria CriteriaBuilder createQuery.

Prototype

<T> CriteriaQuery<T> createQuery(Class<T> resultClass);

Source Link

Document

Create a CriteriaQuery object with the specified result type.

Usage

From source file:bq.jpa.demo.query.criteria.service.CriteriaService.java

/**
 * in and path:/*from  www.j a  v  a  2  s.  c o  m*/
 * SELECT e FROM jpa_query_employee e WHERE e.address.state IN ('NY','MI')
 */
@Transactional
public void doWhere3() {
    CriteriaBuilder cb = em.getCriteriaBuilder();
    CriteriaQuery<Employee> c = cb.createQuery(Employee.class);
    Root<Employee> e = c.from(Employee.class);
    // method 1 
    c.select(e).where(e.get("address").get("state").in("NY", "MI"));
    showResult(c);

    // method 2
    c.select(e).where(cb.in(e.get("address").get("state")).value("NY").value("MI"));
    showResult(c);
}

From source file:bq.jpa.demo.query.criteria.service.CriteriaService.java

/**
 * inner join/*from   w  w  w.  j a  v a 2 s.co m*/
 */
@Transactional
public void doFrom1() {
    CriteriaBuilder cb = em.getCriteriaBuilder();
    CriteriaQuery<Object[]> c = cb.createQuery(Object[].class);
    Root<Employee> e = c.from(Employee.class);
    Join<Object, Object> address = e.join("address");
    Join<Object, Object> department = e.join("department");
    c.multiselect(e, address, department);
    //         .where(cb.and(
    //               cb.equal(address.get("state"), "NY")),
    //               cb.greaterThan(e.<Long>get("salary"), Long.valueOf(1500)), 
    //               cb.like(department.<String>get("name"), "department%"
    //            ));
    showResult(c);
}

From source file:bq.jpa.demo.query.criteria.service.CriteriaService.java

/**
 * subquery: in//w w  w  .j  ava2  s . c  o  m
 * SELECT e FROM jpa_query_employee e WHERE e IN (SELECT emp FROM jpa_query_project p JOIN p.employees pe WHERE p.name = :projectname)
 */
@Transactional
public void doWhere1() {
    CriteriaBuilder cb = em.getCriteriaBuilder();
    CriteriaQuery<Employee> c = cb.createQuery(Employee.class);
    Root<Employee> e = c.from(Employee.class);

    // subquery
    Subquery<Employee> sq = c.subquery(Employee.class);
    Root<Project> p = sq.from(Project.class);
    Join<Project, Employee> pe = p.join("employees");
    sq.select(pe).where(cb.equal(p.get("name"), cb.parameter(String.class, "projectname")));

    //
    c.select(e).where(cb.in(e).value(sq));
}

From source file:com.creditcloud.common.entities.dao.AbstractReadDAO.java

public <K> T findBy(String fieldName, Object value, Class<K> valueClass) {
    EntityManager em = getEntityManager();
    CriteriaBuilder cb = em.getCriteriaBuilder();
    CriteriaQuery<T> cq = cb.createQuery(entityClass);
    Root<T> root = cq.from(entityClass);
    cq.select(root).where(cb.equal(root.get(fieldName).as(valueClass), value));
    List<T> list = em.createQuery(cq).getResultList();
    return list.isEmpty() ? null : list.get(0);
}

From source file:bq.jpa.demo.query.criteria.service.CriteriaService.java

/**
 * subquery(equivalent to dowhere1) : exists
 * SELECT e FROM jpa_query_employee e WHERE EXISTS (SELECT p FROM e.projects p WHERE p.name = :projectname)
 *///  w  ww. j ava  2 s. c  o  m
@Transactional
public void doWhere2() {
    CriteriaBuilder cb = em.getCriteriaBuilder();
    CriteriaQuery<Employee> c = cb.createQuery(Employee.class);
    Root<Employee> e = c.from(Employee.class);

    // subquery
    Subquery<Project> sq = c.subquery(Project.class);
    // Root<Project> p = sq.from(Project.class);
    Root<Employee> se = sq.correlate(e);
    Join<Employee, Project> p = se.join("projects");
    sq.select(p).where(cb.equal(p.get("name"), cb.parameter(String.class, "projectname")));

    //
    c.select(e).where(cb.exists(sq));
}

From source file:bq.jpa.demo.query.criteria.service.CriteriaService.java

/**
 * SELECT e FROM jpa_query_employee e WHERE e.name= :name
 *//*from  ww  w  . j  a va  2  s  .  c  o  m*/
@Transactional
public void doParameterQuery() {
    CriteriaBuilder cb = em.getCriteriaBuilder();
    CriteriaQuery<Employee> c = cb.createQuery(Employee.class);
    Root<Employee> e = c.from(Employee.class);

    // parameter, equal to ":name"
    ParameterExpression<String> paraName = cb.parameter(String.class, "name");

    // e.name = ":name"
    c.select(e).where(cb.equal(e.get("name"), paraName));

    // set param value
    TypedQuery<Employee> query = em.createQuery(c);
    query.setParameter("name", "employee_1");
    List<Employee> result = query.getResultList();
    ResultViewer.showResult(result, "criteria query : parameter query");
}

From source file:bq.jpa.demo.query.criteria.service.CriteriaService.java

/**
 * NOTE : Hibernate cannot support case in criteria way
 * // w w  w  .j  a  v  a  2s . c  om
 * case 1:
 * SELECT p.name, 
 *          CASE WHEN TYPE(p)=bq.jpa.demo.query.domain.DesignProject  THEN 'dev' 
 *              WHEN TYPE(p)=bq.jpa.demo.query.domain.QualityProject THEN 'QA' 
 *              ELSE 'unknown' 
 *          END 
 * FROM jpa_query_project p
 * 
 * case 2:
 * SELECT p.name, 
 *          CASE TYPE(p)
 *              WHEN bq.jpa.demo.query.domain.DesignProject  THEN 'dev' 
 *              WHEN bq.jpa.demo.query.domain.QualityProject THEN 'QA' 
 *              ELSE 'unknown' 
 *          END 
 * FROM jpa_query_project p
 */
@Transactional
public void doWhere4() {
    CriteriaBuilder cb = em.getCriteriaBuilder();
    CriteriaQuery<Object[]> c = cb.createQuery(Object[].class);
    Root<Project> p = c.from(Project.class);

    // method 1
    c.multiselect(p.get("name"), cb.selectCase().when(cb.equal(p.type(), DesignProject.class), "dev")
            .when(cb.equal(p.type(), QualityProject.class), "QA").otherwise("unknown"));

    //      showResult(c);

    // method 2:
    CriteriaQuery<Object[]> c2 = cb.createQuery(Object[].class);
    Root<Project> p2 = c2.from(Project.class);
    c2.multiselect(p2.get("name"), cb.selectCase(p2.type()).when(DesignProject.class, "dev")
            .when(QualityProject.class, "QA").otherwise("unknown"));
    //      showResult(c2);
}

From source file:bq.jpa.demo.query.criteria.service.CriteriaService.java

/**
 * fetch join:/*from  ww  w  .  j av  a2 s  .  c  o m*/
 * SELECT e FROM jpa_query_employee e JOIN FETCH e.address
 */
//   @Transactional
public void doFrom3() {
    CriteriaBuilder cb = em.getCriteriaBuilder();
    CriteriaQuery<Employee> c = cb.createQuery(Employee.class);
    Root<Employee> e = c.from(Employee.class);
    e.fetch("address");
    e.fetch("department");
    e.fetch("projects", JoinType.INNER);
    //      e.fetch("phones");
    //      e.fetch("directs");
    //      e.fetch("manager");
    c.select(e);

    // only show the fetched data
    TypedQuery<Employee> query = em.createQuery(c);
    List<Employee> result = query.getResultList();
    for (Employee emp : result) {
        System.out.println(emp.getId() + " | " + emp.getName() + " | " + emp.getAddress() + " | "
                + emp.getDepartment() + " | " + emp.getProjects());
    }
}

From source file:org.ow2.proactive.scheduling.api.graphql.fetchers.DatabaseConnectionFetcher.java

/**
 * Adaptation of the algorithm defined in the GraphQL specification.
 * <p>// ww w. ja v  a 2 s .  c om
 * Please look at the following link for more details:
 * https://facebook.github.io/relay/graphql/connections.htm#sec-Pagination-algorithm
 * <p>
 * The opaque cursor that is returned to the client makes use of the entity ID internally.
 */
protected ExtendedConnection createPaginatedConnection(DataFetchingEnvironment environment,
        Class<E> entityClass, Function<Root<E>, Path<? extends Number>> entityId,
        Comparator<E> entityComparator, BiFunction<CriteriaBuilder, Root<E>, List<Predicate[]>> criteria,
        CursorMapper<T, Integer> cursorMapper) {

    Integer first = environment.getArgument(FIRST.getName());
    Integer last = environment.getArgument(LAST.getName());

    Integer after = cursorMapper.getOffsetFromCursor(environment.getArgument(AFTER.getName()));
    Integer before = cursorMapper.getOffsetFromCursor(environment.getArgument(BEFORE.getName()));

    CriteriaBuilder criteriaBuilder = entityManager.getCriteriaBuilder();
    CriteriaQuery<E> criteriaQuery = criteriaBuilder.createQuery(entityClass);
    Root<E> entityRoot = criteriaQuery.from(entityClass);
    Path<? extends Number> entityIdPath = entityId.apply(entityRoot);

    Predicate cursorPredicate = createCursorPredicate(criteriaBuilder, entityIdPath, after, before);

    int maxResults = applySlicing(criteriaQuery, criteriaBuilder, entityIdPath, first, last);

    CriteriaQuery<E> select = criteriaQuery.select(entityRoot);

    List<Predicate[]> predicates = criteria.apply(criteriaBuilder, entityRoot);

    Predicate[] wherePredicate = buildWherePredicate(predicates, cursorPredicate, criteriaBuilder);

    if (wherePredicate.length > 0) {
        select.where(wherePredicate);
    }

    TypedQuery<E> query = entityManager.createQuery(select);

    if (maxResults > -1) {
        query.setMaxResults(maxResults);
    }

    Stream<E> dataStream = query.getResultList().stream();

    // if last is provided, reverse the stream
    // in order to get results sorted in ascending order based on entities ID
    if (last != null) {
        dataStream = dataStream.sorted(entityComparator);
    }

    Stream<T> data = dataMapping(dataStream);

    ExtendedConnection connection = createRelayConnection(entityManager, entityClass, criteriaBuilder,
            wherePredicate, cursorMapper, data, first, last);

    return connection;
}

From source file:eu.uqasar.service.AbstractService.java

private List<T> getRange(int first, int count) {
    logger.infof("loading %d %s starting from %d  ...", count, readableClassName, first);
    CriteriaBuilder cb = em.getCriteriaBuilder();
    CriteriaQuery<T> query = cb.createQuery(this.clazz);
    query.from(this.clazz);
    return em.createQuery(query).setFirstResult(first).setMaxResults(count).getResultList();
}