org.hibernate.search.FullTextSession#clear ( )源码实例Demo

@Async
@Transactional(propagation = Propagation.SUPPORTS)
public void reIndex() throws Exception {
	logger.info("Re-Index started");

	FullTextSession fullTextSession = Search.getFullTextSession((entityManager.unwrap(Session.class)));

	fullTextSession.setFlushMode(FlushMode.MANUAL);
	fullTextSession.setCacheMode(CacheMode.IGNORE);

	for (Class persistentClass : fullTextSession.getSearchFactory().getIndexedTypes()) {
		Transaction transaction = fullTextSession.beginTransaction();

		// Scrollable results will avoid loading too many objects in memory
		ScrollableResults results = fullTextSession.createCriteria(persistentClass)
				.setFetchSize(BATCH_SIZE)
				.scroll(ScrollMode.FORWARD_ONLY);
		int index = 0;
		while (results.next()) {
			index++;
			fullTextSession.index(results.get(0)); //index each element
			if (index % BATCH_SIZE == 0) {
				fullTextSession.flushToIndexes(); //apply changes to indexes
				fullTextSession.clear(); //free memory since the queue is processed
			}
		}
		transaction.commit();
	}
	logger.info("Re-Index finished");
}
 

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;
}
 

/**
 * This method contains the primary search functionality for this servlet, and is automatically invoked once for every HTTP
 * POST to the mapped URL. 
 */
@SuppressWarnings("unchecked")
@Override	
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
	
	Logger logger = LoggerFactory.getLogger(SearchServlet.class);
	
	// Get the user's search keyword(s) from CGI variables
	String searchString = request.getParameter("searchString");
	logger.info("Received searchString [" + searchString + "]");

	// Start a Hibernate session.
	Session session = StartupDataLoader.openSession();
	
	// Create a Hibernate Search wrapper around the vanilla Hibernate session
	FullTextSession fullTextSession = Search.getFullTextSession(session);

	// Begin a transaction.  This may not be strictly necessary, but is a good practice in general.
	fullTextSession.beginTransaction();

	// Create a Hibernate Search QueryBuilder for the appropriate Lucene index (i.e. the index for "App" in this case)
	QueryBuilder queryBuilder = fullTextSession.getSearchFactory().buildQueryBuilder().forEntity( App.class ).get();
	
	// Use the QueryBuilder to construct a Lucene keyword query... matching the user's search keywords against the "name" 
	// and "description" fields of App, as well as "name" field of associated Device entities, and the "comments" field of
	// embedded CustomerReview objects.
	org.apache.lucene.search.Query luceneQuery = queryBuilder
		.keyword()
		.onFields("name", "description", "supportedDevices.name", "customerReviews.comments")
		.matching(searchString)
		.createQuery();
	org.hibernate.Query hibernateQuery = fullTextSession.createFullTextQuery(luceneQuery, App.class);
	
	List<App> apps = hibernateQuery.list();
	logger.info("Found " + apps.size() + " apps");

	// Detach the results from the Hibernate session (to prevent unwanted interaction between the view layer 
	// and Hibernate when associated devices or embedded customer reviews are referenced)
	fullTextSession.clear();

	// Put the search results on the HTTP reqeust object
	request.setAttribute("apps", apps);

	// Close and clean up the Hibernate session
	fullTextSession.getTransaction().commit();
	session.close();
	
	// Forward the request object (including the search results) to the JSP/JSTL view for rendering
	getServletContext().getRequestDispatcher("/WEB-INF/pages/search.jsp").forward(request, response);
}
 

/**
 * This method contains the primary search functionality for this servlet, and is automatically invoked once for every HTTP
 * POST to the mapped URL. 
 */
@SuppressWarnings("unchecked")
@Override	
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
	
	Logger logger = LoggerFactory.getLogger(SearchServlet.class);
	
	// Get the user's search keyword(s) from CGI variables
	String searchString = request.getParameter("searchString");
	logger.info("Received searchString [" + searchString + "]");

	// Start a Hibernate session.
	Session session = StartupDataLoader.openSession();
	
	// Create a Hibernate Search wrapper around the vanilla Hibernate session
	FullTextSession fullTextSession = Search.getFullTextSession(session);

	// Begin a transaction.  This may not be strictly necessary, but is a good practice in general.
	fullTextSession.beginTransaction();

	// Create a Hibernate Search QueryBuilder for the appropriate Lucene index (i.e. the index for "App" in this case)
	QueryBuilder queryBuilder = fullTextSession.getSearchFactory().buildQueryBuilder().forEntity( App.class ).get();
	
	// Use the QueryBuilder to construct a Lucene keyword query... matching the user's search keywords against the "name" 
	// and "description" fields of App, as well as "name" field of associated Device entities, and the "comments" field of
	// embedded CustomerReview objects.
	org.apache.lucene.search.Query luceneQuery = queryBuilder
		.keyword()
		.onFields("name", "description", "supportedDevices.name", "customerReviews.comments")
		.matching(searchString)
		.createQuery();
	org.hibernate.Query hibernateQuery = fullTextSession.createFullTextQuery(luceneQuery, App.class);
	
	List<App> apps = hibernateQuery.list();
	logger.info("Found " + apps.size() + " apps");

	// Detach the results from the Hibernate session (to prevent unwanted interaction between the view layer 
	// and Hibernate when associated devices or embedded customer reviews are referenced)
	fullTextSession.clear();

	// Put the search results on the HTTP reqeust object
	request.setAttribute("apps", apps);

	// Close and clean up the Hibernate session
	fullTextSession.getTransaction().commit();
	session.close();
	
	// Forward the request object (including the search results) to the JSP/JSTL view for rendering
	getServletContext().getRequestDispatcher("/WEB-INF/pages/search.jsp").forward(request, response);
}
 

/**
 * This method contains the primary search functionality for this servlet, and is automatically invoked once for every HTTP
 * POST to the mapped URL. 
 */
@SuppressWarnings("unchecked")
@Override	
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
	
	Logger logger = LoggerFactory.getLogger(SearchServlet.class);
	
	// Get the user's search keyword(s) from CGI variables
	String searchString = request.getParameter("searchString");
	logger.info("Received searchString [" + searchString + "]");

	// Start a Hibernate session.
	Session session = StartupDataLoader.openSession();
	
	// Create a Hibernate Search wrapper around the vanilla Hibernate session
	FullTextSession fullTextSession = Search.getFullTextSession(session);

	// Begin a transaction.  This may not be strictly necessary, but is a good practice in general.
	fullTextSession.beginTransaction();

	// Create a Hibernate Search QueryBuilder for the appropriate Lucene index (i.e. the index for "App" in this case)
	QueryBuilder queryBuilder = fullTextSession.getSearchFactory().buildQueryBuilder().forEntity( App.class ).get();
	
	// Use the QueryBuilder to construct a Lucene keyword query... matching the user's search keywords against the "name" 
	// and "description" fields of App, as well as "name" field of associated Device entities, and the "comments" field of
	// embedded CustomerReview objects.
	org.apache.lucene.search.Query luceneQuery = queryBuilder
		.keyword()
		.onFields("name", "description", "supportedDevices.name", "customerReviews.comments")
		.matching(searchString)
		.createQuery();
	org.hibernate.Query hibernateQuery = fullTextSession.createFullTextQuery(luceneQuery, App.class);
	
	List<App> apps = hibernateQuery.list();
	logger.info("Found " + apps.size() + " apps");

	// Detach the results from the Hibernate session (to prevent unwanted interaction between the view layer 
	// and Hibernate when associated devices or embedded customer reviews are referenced)
	fullTextSession.clear();

	// Put the search results on the HTTP reqeust object
	request.setAttribute("apps", apps);

	// Close and clean up the Hibernate session
	fullTextSession.getTransaction().commit();
	session.close();
	
	// Forward the request object (including the search results) to the JSP/JSTL view for rendering
	getServletContext().getRequestDispatcher("/WEB-INF/pages/search.jsp").forward(request, response);
}