Java Code Examples for org.hibernate.ScrollableResults#next()

@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)));
}
 

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 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);
		}
	}

}
 

protected int doRebuildIndex() throws Exception {
	FullTextSession fullTextSession = (FullTextSession) entityManager.getDelegate();
	fullTextSession.setFlushMode(org.hibernate.FlushMode.MANUAL);
	fullTextSession.setCacheMode(org.hibernate.CacheMode.IGNORE);
	fullTextSession.purgeAll(NodeDocumentVersion.class);
	fullTextSession.getSearchFactory().optimize(NodeDocumentVersion.class);

	String query = "select ndv from NodeDocumentVersion ndv";
	ScrollableResults cursor = fullTextSession.createQuery(query).scroll();
	cursor.last();
	int count = cursor.getRowNumber() + 1;
	log.warn("Re-building Wine index for " + count + " objects.");

	if (count > 0) {
		int batchSize = 300;
		cursor.first(); // Reset to first result row
		int i = 0;

		while (true) {
			fullTextSession.index(cursor.get(0));

			if (++i % batchSize == 0) {
				fullTextSession.flushToIndexes();
				fullTextSession.clear(); // Clear persistence context for each batch
				log.info("Flushed index update " + i + " from Thread "
						+ Thread.currentThread().getName());
			}

			if (cursor.isLast()) {
				break;
			}

			cursor.next();
		}
	}

	cursor.close();
	fullTextSession.flushToIndexes();
	fullTextSession.clear(); // Clear persistence context for each batch
	fullTextSession.getSearchFactory().optimize(NodeDocumentVersion.class);

	return count;
}
 

public void testCurrentSessionWithScroll() throws Exception {
	DummyTransactionManager.INSTANCE.begin();
	Session s = getSessions().getCurrentSession();
	Map item1 = new HashMap();
	item1.put( "name", "Item - 1" );
	item1.put( "description", "The first item" );
	s.persist( "Item", item1 );

	Map item2 = new HashMap();
	item2.put( "name", "Item - 2" );
	item2.put( "description", "The second item" );
	s.persist( "Item", item2 );
	DummyTransactionManager.INSTANCE.getTransaction().commit();

	// First, test partially scrolling the result with out closing
	DummyTransactionManager.INSTANCE.begin();
	s = getSessions().getCurrentSession();
	ScrollableResults results = s.createQuery( "from Item" ).scroll();
	results.next();
	DummyTransactionManager.INSTANCE.getTransaction().commit();

	// Next, test partially scrolling the result with closing
	DummyTransactionManager.INSTANCE.begin();
	s = getSessions().getCurrentSession();
	results = s.createQuery( "from Item" ).scroll();
	results.next();
	results.close();
	DummyTransactionManager.INSTANCE.getTransaction().commit();

	// Next, scroll the entire result (w/o closing)
	DummyTransactionManager.INSTANCE.begin();
	s = getSessions().getCurrentSession();
	results = s.createQuery( "from Item" ).scroll();
	while ( !results.isLast() ) {
		results.next();
	}
	DummyTransactionManager.INSTANCE.getTransaction().commit();

	// Next, scroll the entire result (closing)
	DummyTransactionManager.INSTANCE.begin();
	s = getSessions().getCurrentSession();
	results = s.createQuery( "from Item" ).scroll();
	while ( !results.isLast() ) {
		results.next();
	}
	results.close();
	DummyTransactionManager.INSTANCE.getTransaction().commit();

	DummyTransactionManager.INSTANCE.begin();
	s = getSessions().getCurrentSession();
	s.createQuery( "delete from Item" ).executeUpdate();
	DummyTransactionManager.INSTANCE.getTransaction().commit();
}
 

public void testScrollableIterator() throws Exception {
	if ( getDialect() instanceof DB2Dialect || getDialect() instanceof OracleDialect || getDialect() instanceof SybaseDialect || getDialect() instanceof HSQLDialect ) {
		Session s = openSession();
		Transaction txn = s.beginTransaction();
		s.save( new Foo() );
		s.save( new Foo() );
		s.save( new Foo() );
		s.save( new Bar() );
		Query query = s.createQuery("select f, f.integer from Foo f");
		assertTrue( query.getReturnTypes().length==2 );
		ScrollableResults iter = query.scroll();
		assertTrue( iter.next() );
		assertTrue( iter.scroll(1) );
		FooProxy f2 = (FooProxy) iter.get()[0];
		assertTrue( f2!=null );
		assertTrue( iter.scroll(-1) );
		Object f1 = iter.get(0);
		iter.next();
		assertTrue( f1!=null && iter.get(0)==f2 );
		iter.getInteger(1);

		assertTrue( !iter.scroll(100) );
		assertTrue( iter.first() );
		assertTrue( iter.scroll(3) );
		Object f4 = iter.get(0);
		assertTrue( f4!=null );
		assertTrue( !iter.next() );
		assertTrue( iter.first() );
		assertTrue( iter.get(0)==f1 );
		assertTrue( iter.last() );
		assertTrue( iter.get(0)==f4 );
		assertTrue( iter.previous() );
		txn.commit();
		s.close();

		s = openSession();
		txn = s.beginTransaction();
		query = s.createQuery("select f, f.integer from Foo f");
		assertTrue( query.getReturnTypes().length==2 );
		iter = query.scroll();
		assertTrue( iter.next() );
		assertTrue( iter.scroll(1) );
		f2 = (FooProxy) iter.get()[0];
		assertTrue( f2!=null );
		assertTrue( f2.getString()!=null  && f2.getComponent().getImportantDates().length > 0 );
		assertTrue( iter.scroll(-1) );
		f1 = iter.get(0);
		iter.next();
		assertTrue( f1!=null && iter.get(0)==f2 );
		iter.getInteger(1);

		assertTrue( !iter.scroll(100) );
		assertTrue( iter.first() );
		assertTrue( iter.scroll(3) );
		f4 = iter.get(0);
		assertTrue( f4!=null );
		assertTrue( !iter.next() );
		assertTrue( iter.first() );
		assertTrue( iter.get(0)==f1 );
		assertTrue( iter.last() );
		assertTrue( iter.get(0)==f4 );
		assertTrue( iter.previous() );
		assertTrue( s.delete("from Foo")==4 );
		s.flush();
		assertTrue( s.find("from java.lang.Object").size()==0 );
		txn.commit();
		s.close();
	}
}
 

public void testCreateUpdateReadDelete() {
	StatelessSession ss = getSessions().openStatelessSession();
	Transaction tx = ss.beginTransaction();
	Document doc = new Document("blah blah blah", "Blahs");
	ss.insert(doc);
	assertNotNull( doc.getName() );
	Date initVersion = doc.getLastModified();
	assertNotNull( initVersion );
	tx.commit();
	
	tx = ss.beginTransaction();
	doc.setText("blah blah blah .... blah");
	ss.update(doc);
	assertNotNull( doc.getLastModified() );
	assertNotSame( doc.getLastModified(), initVersion );
	tx.commit();
	
	tx = ss.beginTransaction();
	doc.setText("blah blah blah .... blah blay");
	ss.update(doc);
	tx.commit();
	
	Document doc2 = (Document) ss.get(Document.class.getName(), "Blahs");
	assertEquals("Blahs", doc2.getName());
	assertEquals(doc.getText(), doc2.getText());
			
	doc2 = (Document) ss.createQuery("from Document where text is not null").uniqueResult();
	assertEquals("Blahs", doc2.getName());
	assertEquals(doc.getText(), doc2.getText());
	
	ScrollableResults sr = ss.createQuery("from Document where text is not null")
		.scroll(ScrollMode.FORWARD_ONLY);
	sr.next();
	doc2 = (Document) sr.get(0);
	sr.close();
	assertEquals("Blahs", doc2.getName());
	assertEquals(doc.getText(), doc2.getText());
			
	doc2 = (Document) ss.createSQLQuery("select * from Document")
		.addEntity(Document.class)
		.uniqueResult();
	assertEquals("Blahs", doc2.getName());
	assertEquals(doc.getText(), doc2.getText());
			
	doc2 = (Document) ss.createCriteria(Document.class).uniqueResult();
	assertEquals("Blahs", doc2.getName());
	assertEquals(doc.getText(), doc2.getText());
	
	sr = ss.createCriteria(Document.class).scroll(ScrollMode.FORWARD_ONLY);
	sr.next();
	doc2 = (Document) sr.get(0);
	sr.close();
	assertEquals("Blahs", doc2.getName());
	assertEquals(doc.getText(), doc2.getText());

	tx = ss.beginTransaction();
	ss.delete(doc);
	tx.commit();
	ss.close();

}
 

public Integer index(IndexWriter writer, Integer siteId, Integer channelId,
		Date startDate, Date endDate, Integer startId, Integer max)
		throws CorruptIndexException, IOException {
	Finder f = Finder.create("select bean from Content bean");
	if (channelId != null) {
		f.append(" join bean.channel channel, Channel parent");
		f.append(" where channel.lft between parent.lft and parent.rgt");
		f.append(" and channel.site.id=parent.site.id");
		f.append(" and parent.id=:parentId");
		f.setParam("parentId", channelId);
	} else if (siteId != null) {
		f.append(" where bean.site.id=:siteId");
		f.setParam("siteId", siteId);
	} else {
		f.append(" where 1=1");
	}
	if (startId != null) {
		f.append(" and bean.id > :startId");
		f.setParam("startId", startId);
	}
	if (startDate != null) {
		f.append(" and bean.contentExt.releaseDate >= :startDate");
		f.setParam("startDate", startDate);
	}
	if (endDate != null) {
		f.append(" and bean.contentExt.releaseDate <= :endDate");
		f.setParam("endDate", endDate);
	}
	f.append(" and bean.status=" + ContentCheck.CHECKED);
	f.append(" order by bean.id asc");
	if (max != null) {
		f.setMaxResults(max);
	}
	Session session = getSession();
	ScrollableResults contents = f.createQuery(getSession()).setCacheMode(
			CacheMode.IGNORE).scroll(ScrollMode.FORWARD_ONLY);
	int count = 0;
	Content content = null;
	while (contents.next()) {
		content = (Content) contents.get(0);
		writer.addDocument(LuceneContent.createDocument(content));
		if (++count % 20 == 0) {
			session.clear();
		}
	}
	if (count < max || content == null) {
		// 实际数量小于指定数量，代表生成结束。如果没有任何数据，也代表生成结束。
		return null;
	} else {
		// 返回最后一个ID
		return content.getId();
	}

}