org.hibernate.ScrollableResults Java Examples

public void testScrollCriteria() {
	Session session = openSession();
	Transaction t = session.beginTransaction();

	Course course = new Course();
	course.setCourseCode("HIB");
	course.setDescription("Hibernate Training");
	session.persist(course);
	session.flush();
	session.clear();
	ScrollableResults sr = session.createCriteria(Course.class).scroll();
	assertTrue( sr.next() );
	course = (Course) sr.get(0);
	assertNotNull(course);
	sr.close();
	session.delete(course);
	
	t.commit();
	session.close();
	
}
 

@Test
void performScrollLuceneIndexSearch() {
    try (ScrollableResults scroll = createNonJpaFullTextQuery(createQueryForDog1()).scroll()) {
        assertThat(scroll.next()).isTrue();

        assertAll(() -> {
            Object[] dogs = scroll.get();
            assertThat(dogs.length).isEqualTo(1);
            assertThat(((Dog) dogs[0]).getName()).isEqualTo("dog1");
            assertThat(scroll.isFirst()).isTrue();
            assertThat(scroll.isLast()).isTrue();

            assertApmSpanInformation(reporter, "name:dog1", "scroll");
        });
    }
}
 

@Test
public void test_hql_api_scroll_projection_example() {
	doInJPA( this::entityManagerFactory, entityManager -> {
		Session session = entityManager.unwrap( Session.class );
		//tag::hql-api-scroll-example[]
		try ( ScrollableResults scrollableResults = session.createQuery(
				"select p " +
				"from Person p " +
				"where p.name like :name" )
				.setParameter( "name", "J%" )
				.scroll()
		) {
			while(scrollableResults.next()) {
				Person person = (Person) scrollableResults.get()[0];
				process(person);
			}
		}
		//end::hql-api-scroll-example[]
	});
}
 

@Override
public Long getStoppedCollectionsCount(String terms) {
	Criteria criteria = getHibernateTemplate().getSessionFactory().getCurrentSession().createCriteria(Collection.class);
	criteria.setProjection(Projections.projectionList()
			.add(Projections.property("id"), "id"));
	
	LogicalExpression or = Restrictions.or(
			Restrictions.eq("status", CollectionStatus.STOPPED),
			Restrictions.eq("status", CollectionStatus.NOT_RUNNING)
			);
	
	LogicalExpression orAll = Restrictions.or(
			or,
			Restrictions.eq("status", CollectionStatus.FATAL_ERROR)
			);
	
	criteria.add(orAll);
	addCollectionSearchCriteria(terms, criteria);

	ScrollableResults scroll = criteria.scroll();
	int i = scroll.last() ? scroll.getRowNumber() + 1 : 0;
	return Long.valueOf(i);
}
 

@Test
public void test_hql_api_scroll_open_example() {
	ScrollableResults scrollableResults = doInJPA( this::entityManagerFactory, entityManager -> {
		Session session = entityManager.unwrap( Session.class );
		return session.createQuery(
			"select p " +
			"from Person p " +
			"where p.name like :name" )
		.setParameter( "name", "J%" )
		.scroll();
	});
	try {
		scrollableResults.next();
		fail("Should throw exception because the ResultSet must be closed by now!");
	}
	catch ( Exception expected ) {
	}
}
 

@Test
public final void givenUsingTheScrollableApi_whenRetrievingPaginatedData_thenCorrect() {
    final int pageSize = 10;
    final String hql = "FROM Foo f order by f.name";
    final Query query = session.createQuery(hql);

    final ScrollableResults resultScroll = query.scroll(ScrollMode.FORWARD_ONLY);

    // resultScroll.last();
    // final int totalResults = resultScroll.getRowNumber() + 1;

    resultScroll.first();
    resultScroll.scroll(0);
    final List<Foo> fooPage = Lists.newArrayList();
    int i = 0;
    while (pageSize > i++) {
        fooPage.add((Foo) resultScroll.get(0));
        if (!resultScroll.next()) {
            break;
        }
    }

    assertThat(fooPage, hasSize(lessThan(10 + 1)));
}
 

/**
 * Runs the query by calling <code>org.hibernate.Query.scroll()</code>.
 * 
 * @return scrollable results of the query
 */
public ScrollableResults scroll()
{
	setMaxCount();
	
	setQueryRunning(true);
	try
	{
		scrollableResults = query.scroll(ScrollMode.FORWARD_ONLY);
	}
	finally
	{
		setQueryRunning(false);
	}
	
	return scrollableResults;
}
 

public ScrollableResults performScroll(
		QueryParameters queryParameters,
        SessionImplementor session) throws HibernateException {
	if ( log.isTraceEnabled() ) {
		log.trace( "iterate: " + getSourceQuery() );
		queryParameters.traceParameters( session.getFactory() );
	}
	if ( translators.length != 1 ) {
		throw new QueryException( "implicit polymorphism not supported for scroll() queries" );
	}
	if ( queryParameters.getRowSelection().definesLimits() && translators[0].containsCollectionFetches() ) {
		throw new QueryException( "firstResult/maxResults not supported in conjunction with scroll() of a query containing collection fetches" );
	}

	return translators[0].scroll( queryParameters, session );
}
 

public ScrollableResults scroll(CriteriaImpl criteria, ScrollMode scrollMode) {
	errorIfClosed();
	checkTransactionSynchStatus();
	String entityName = criteria.getEntityOrClassName();
	CriteriaLoader loader = new CriteriaLoader(
			getOuterJoinLoadable(entityName),
			factory,
			criteria,
			entityName,
			getEnabledFilters()
	);
	autoFlushIfRequired( loader.getQuerySpaces() );
	dontFlushFromFind++;
	try {
		return loader.scroll(this, scrollMode);
	}
	finally {
		dontFlushFromFind--;
	}
}
 

public ScrollableResults scrollCustomQuery(CustomQuery customQuery, QueryParameters queryParameters) 
throws HibernateException {
	errorIfClosed();
	checkTransactionSynchStatus();

	if ( log.isTraceEnabled() ) {
		log.trace( "scroll SQL query: " + customQuery.getSQL() );
	}

	CustomLoader loader = new CustomLoader( customQuery, getFactory() );

	autoFlushIfRequired( loader.getQuerySpaces() );

	dontFlushFromFind++; //stops flush being called multiple times if this method is recursively called
	try {
		return loader.scroll(queryParameters, this);
	}
	finally {
		dontFlushFromFind--;
	}
}
 

public ScrollableResults scroll(ScrollMode scrollMode) throws HibernateException {
	verifyParameters();
	before();

	Map namedParams = getNamedParams();
	NativeSQLQuerySpecification spec = generateQuerySpecification( namedParams );

	QueryParameters qp = getQueryParameters( namedParams );
	qp.setScrollMode( scrollMode );

	try {
		return getSession().scroll( spec, qp );
	}
	finally {
		after();
	}
}
 

@Override
public void execute() {
	LOG.info("executing " + getClass().getSimpleName());
	if (env.supports("feature.newsletter")) {
		LOG.info("sending newsletter emails");
		ScrollableResults results = users.moderators();
		newsMailer.sendTo(results, true);
		result.notFound();
	}
}
 

@Override
public Iterator<MarketOrder> getIterator(final Currency currency, final Currency commodityCurrency) {
	final String queryString = "FROM MarketOrderImpl m "
			+ "WHERE m.currency = :currency AND m.commodityCurrency = :commodityCurrency "
			+ "ORDER BY m.pricePerUnit ASC";
	final ScrollableResults itemCursor = getSession().createQuery(queryString).setParameter("currency", currency)
			.setParameter("commodityCurrency", commodityCurrency).scroll(ScrollMode.FORWARD_ONLY);
	return new HibernateIteratorImpl<MarketOrder>(itemCursor);
}
 

public void sendTo(ScrollableResults results, boolean isTestNewsletter) {
	DateTime pastWeek = new DateTime().minusWeeks(1);
	DateTime twelveHoursAgo = new DateTime().minusHours(12);
	List<News> hotNews = news.hotNews();
	List<Question> hotQuestions = questions.hot(pastWeek, 8);
	List<Question> unanswered = questions.randomUnanswered(pastWeek, twelveHoursAgo, 8);
	LinkToHelper linkToHelper = new NotificationMailer.LinkToHelper(router, brutalEnv);
	String siteName = bundle.getMessage("site.name");
	String date = brutalDateFormat.getInstance("date.joda.newsletter.pattern").print(new DateTime());
	
	String teste = isTestNewsletter ? bundle.getMessage("newsletter_mail_test") : "";
	
	while (results.next()) {
		User user = (User) results.get()[0];
		try {
			Email email = templates.template("newsletter_mail", date, siteName, teste)
					.with("hotNews", hotNews)
					.with("hotQuestions", hotQuestions)
					.with("unansweredQuestions", unanswered)
					.with("unsubscribeLink", linkToHelper.unsubscribeLink(user))
					.with("linkToHelper", linkToHelper)
					.with("l10n", bundle)
					.with("sanitizer", POLICY)
					.with("siteName", siteName)
					.with("date", date)
					.with("logoUrl", env.get("mail_logo_url"))
					.to(user.getName(), user.getEmail());
			email.setCharset("utf-8");
			mailer.send(email);
		} catch (Exception e) {
			LOG.error("could not send email", e);
		}
	}

}
 

@Override
@Path("/wjh1jkh34jk12hkjehd13kj4h1kjh41jkhwe12341")
public void execute() {
	LOG.info("executing " + getClass().getSimpleName());
	if (shouldSendNewsletter()) {
		LOG.info("sending newsletter emails");
		ScrollableResults results = users.newsletterConfirmed();
		newsMailer.sendTo(results, false);
		newsletterSentLogs.saveLog();
		result.notFound();
	}
}
 

protected int getTotalNumber(Criteria criteria) {
	ScrollableResults results = criteria.scroll();
	results.last();
	int total = results.getRowNumber() + 1;
	results.close();
	return total;
}
 

public void testScrollingJoinFetchesPositioning() {
	TestData data = new TestData();
	data.prepare();

	Session s = openSession();
	Transaction txn = s.beginTransaction();

	ScrollableResults results = s
	        .createQuery( "from Animal a left join fetch a.offspring where a.description like :desc order by a.id" )
	        .setString( "desc", "root%" )
	        .scroll();

	results.first();
	Animal animal = ( Animal ) results.get( 0 );
	assertEquals( "first() did not return expected row", data.root1Id, animal.getId() );

	results.scroll( 1 );
	animal = ( Animal ) results.get( 0 );
	assertEquals( "scroll(1) did not return expected row", data.root2Id, animal.getId() );

	results.scroll( -1 );
	animal = ( Animal ) results.get( 0 );
	assertEquals( "scroll(-1) did not return expected row", data.root1Id, animal.getId() );

	results.setRowNumber( 1 );
	animal = ( Animal ) results.get( 0 );
	assertEquals( "setRowNumber(1) did not return expected row", data.root1Id, animal.getId() );

	results.setRowNumber( 2 );
	animal = ( Animal ) results.get( 0 );
	assertEquals( "setRowNumber(2) did not return expected row", data.root2Id, animal.getId() );

	txn.commit();
	s.close();

	data.cleanup();
}
 

public ScrollableResults scroll(String query, QueryParameters queryParameters) throws HibernateException {
	errorIfClosed();
	checkTransactionSynchStatus();
	HQLQueryPlan plan = getHQLQueryPlan( query, false );
	autoFlushIfRequired( plan.getQuerySpaces() );
	dontFlushFromFind++;
	try {
		return plan.performScroll( queryParameters, this );
	}
	finally {
		dontFlushFromFind--;
	}
}
 

public MessageLoader(ScrollableResults results, Session session) {
    this.results = results;
    this.session = session;
    results.last();
    numberOfRecords = results.getRowNumber() + 1;
    results.beforeFirst();
}
 

private int getResultNumberUsingScrollableResults(org.hibernate.Query hibernateQuery, Session session) {
	int resultNumber = 0;
	logger.debug("Scrolling query " + statement.getQueryString() + " ...");
	ScrollableResults scrollableResults = hibernateQuery.scroll();
	scrollableResults.last();
	logger.debug("Scrolled query " + statement.getQueryString());
	resultNumber = scrollableResults.getRowNumber() + 1; // Hibernate ScrollableResults row number starts with 0
	logger.debug("Number of fetched records: " + resultNumber + " for query " + statement.getQueryString());
	resultNumber = resultNumber < 0 ? 0 : resultNumber;
	return resultNumber;
}
 

public void testScrollingJoinFetchesReverse() {
	TestData data = new TestData();
	data.prepare();

	Session s = openSession();
	Transaction txn = s.beginTransaction();

	ScrollableResults results = s
	        .createQuery( "from Animal a left join fetch a.offspring where a.description like :desc order by a.id" )
	        .setString( "desc", "root%" )
	        .scroll();

	results.afterLast();

	int counter = 0;
	while ( results.previous() ) {
		counter++;
		Animal animal = ( Animal ) results.get( 0 );
		checkResult( animal );
	}
	assertEquals( "unexpected result count", 2, counter );

	txn.commit();
	s.close();

	data.cleanup();
}
 

public void testScrollingJoinFetchesForward() {
	if ( ! supportsResultSetPositionQueryMethodsOnForwardOnlyCursor() ) {
		return;
	}

	TestData data = new TestData();
	data.prepare();

	Session s = openSession();
	Transaction txn = s.beginTransaction();

	ScrollableResults results = s
	        .createQuery( "from Animal a left join fetch a.offspring where a.description like :desc order by a.id" )
	        .setString( "desc", "root%" )
			.scroll( ScrollMode.FORWARD_ONLY );

	int counter = 0;
	while ( results.next() ) {
		counter++;
		Animal animal = ( Animal ) results.get( 0 );
		checkResult( animal );
	}
	assertEquals( "unexpected result count", 2, counter );

	txn.commit();
	s.close();

	data.cleanup();
}
 

public ScrollableResults scroll(ScrollMode scrollMode) throws HibernateException {
	verifyParameters();
	Map namedParams = getNamedParams();
	before();
	QueryParameters qp = getQueryParameters(namedParams);
	qp.setScrollMode(scrollMode);
	try {
		return getSession().scroll( expandParameterLists(namedParams), qp );
	}
	finally {
		after();
	}
}
 

public ScrollableResults scroll(ScrollMode scrollMode) {
	before();
	try {
		return session.scroll(this, scrollMode);
	}
	finally {
		after();
	}
}
 

public void testScroll() throws Exception {
	getSessions().getStatistics().clear();
	Session s = openSession();
	Transaction t = s.beginTransaction();
	Item i1 = new Item("foo");
	Item i2 = new Item("bar");
	s.persist("Item", i1);
	s.persist("Item", i2);
	t.commit();
	s.close();

	s = openSession();
	t = s.beginTransaction();
	ScrollableResults sr = s.getNamedQuery("Item.nameDesc").scroll();
	assertTrue( sr.next() );
	i1 = (Item) sr.get(0);
	assertTrue( sr.next() );
	i2 = (Item) sr.get(0);
	assertTrue( Hibernate.isInitialized(i1) );
	assertTrue( Hibernate.isInitialized(i2) );
	assertEquals( i1.getName(), "foo" );
	assertEquals( i2.getName(), "bar" );
	assertFalse( sr.next() );
	s.delete(i1);
	s.delete(i2);
	t.commit();
	s.close();
	assertEquals( getSessions().getStatistics().getEntityFetchCount(), 0 );
}
 

public void testQueryScrolling() throws Throwable {
	prepare();
	Session s = getSessionUnderTest();
	Silly silly = new Silly( "silly" );
	s.save( silly );
	s.flush();

	ScrollableResults sr = s.createQuery( "from Silly" ).scroll();
	assertTrue( sr.next() );
	Silly silly2 = ( Silly ) sr.get( 0 );
	assertEquals( silly, silly2 );
	sr.close();

	sr = s.createQuery( "from Silly" ).scroll();
	ScrollableResults sr2 = s.createQuery( "from Silly where name = 'silly'" ).scroll();

	assertTrue( sr.next() );
	assertEquals( silly, sr.get( 0 ) );
	assertTrue( sr2.next() );
	assertEquals( silly, sr2.get( 0 ) );

	sr.close();
	sr2.close();

	s.delete( silly );
	s.flush();

	release( s );
	done();
}
 

public ScrollableResults scroll(CriteriaImpl criteria, ScrollMode scrollMode) {
	errorIfClosed();
	String entityName = criteria.getEntityOrClassName();
	CriteriaLoader loader = new CriteriaLoader(
			getOuterJoinLoadable(entityName),
	        factory,
	        criteria,
	        entityName,
	        getEnabledFilters()
		);
	return loader.scroll(this, scrollMode);
}
 

public void testSerializationFailsOnAfterStatementAggressiveReleaseWithOpenResources() throws Throwable {
	prepare();
	Session s = getSessionUnderTest();

	Silly silly = new Silly( "silly" );
	s.save( silly );

	// this should cause the CM to obtain a connection, and then release it
	s.flush();

	// both scroll() and iterate() cause the batcher to hold on
	// to resources, which should make aggresive-release not release
	// the connection (and thus cause serialization to fail)
	ScrollableResults sr = s.createQuery( "from Silly" ).scroll();

	try {
		SerializationHelper.serialize( s );
		fail( "Serialization allowed on connected session; or aggressive release released connection with open resources" );
	}
	catch( IllegalStateException e ) {
		// expected behavior
	}

	// Closing the ScrollableResults does currently force the batcher to
	// aggressively release the connection
	sr.close();
	SerializationHelper.serialize( s );

	s.delete( silly );
	s.flush();

	release( s );
	done();
}
 

/**
 * Return the query results, as an instance of <tt>ScrollableResults</tt>
 */
public ScrollableResults scroll(QueryParameters queryParameters, SessionImplementor session)
		throws HibernateException {
	// Delegate to the QueryLoader...
	errorIfDML();
	return queryLoader.scroll( queryParameters, session );
}
 

@Override
public ScrollableResults scroll(ScrollMode scrollMode) {
	before();
	try {
		return session.scroll(this, scrollMode);
	}
	finally {
		after();
	}
}