HHH-9573 : Add EntityManager test case illustrating usage of query cache

(cherry picked from commit 3cc8cb3113)

hibernate-entitymanager/src/test/java/org/hibernate/jpa/test/query/CachedQueryTest.java

@@ -0,0 +1,190 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * Copyright (c) 2015, Red Hat Inc. or third-party contributors as
+ * indicated by the @author tags or express copyright attribution
+ * statements applied by the authors.  All third-party contributions are
+ * distributed under license by Red Hat Inc.
+ *
+ * This copyrighted material is made available to anyone wishing to use, modify,
+ * copy, or redistribute it subject to the terms and conditions of the GNU
+ * Lesser General Public License, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this distribution; if not, write to:
+ * Free Software Foundation, Inc.
+ * 51 Franklin Street, Fifth Floor
+ * Boston, MA  02110-1301  USA
+ */
+package org.hibernate.jpa.test.query;
+
+import java.util.List;
+import java.util.Map;
+import javax.persistence.EntityManager;
+import javax.persistence.SharedCacheMode;
+import javax.persistence.TypedQuery;
+
+import org.junit.Test;
+
+import org.hibernate.cfg.Environment;
+import org.hibernate.jpa.AvailableSettings;
+import org.hibernate.jpa.HibernateEntityManagerFactory;
+import org.hibernate.jpa.spi.HibernateEntityManagerImplementor;
+import org.hibernate.jpa.QueryHints;
+import org.hibernate.jpa.test.BaseEntityManagerFunctionalTestCase;
+import org.hibernate.stat.Statistics;
+import org.hibernate.testing.TestForIssue;
+
+import static org.junit.Assert.assertEquals;
+
+/**
+ * @author Gail Badner
+ */
+@TestForIssue( jiraKey = "HHH-9573" )
+public class CachedQueryTest extends BaseEntityManagerFunctionalTestCase {
+
+	@Test
+	public void testCacheableQuery() {
+		EntityManager em = getOrCreateEntityManager();
+		em.getTransaction().begin();
+		for ( int i = 0 ; i < 10 ; i++ ) {
+			Employee employee = new Employee( "John" + i, 20d + i);
+			em.persist( employee );
+		}
+		em.getTransaction().commit();
+		em.close();
+
+		HibernateEntityManagerFactory hemf =  (HibernateEntityManagerFactory) entityManagerFactory();
+		Statistics stats = hemf.getSessionFactory().getStatistics();
+
+		assertEquals( 0, stats.getQueryCacheHitCount() );
+		assertEquals( 0, stats.getQueryCacheMissCount() );
+		assertEquals( 0, stats.getQueryCachePutCount() );
+		assertEquals( 0, stats.getSecondLevelCacheHitCount() );
+		assertEquals( 0, stats.getSecondLevelCacheMissCount() );
+		assertEquals( 10, stats.getSecondLevelCachePutCount() );
+
+		stats.clear();
+
+		em = getOrCreateEntityManager();
+		em.getTransaction().begin();
+
+		// First time the query is executed, query and results are cached.
+
+		TypedQuery<Employee> query = em.createQuery( "select e from Employee e", Employee.class )
+				.setHint( QueryHints.HINT_CACHEABLE, true );
+		List<Employee> employees = query.getResultList();
+		assertEquals( 10, employees.size() );
+		assertEquals( 0, stats.getQueryCacheHitCount() );
+		assertEquals( 1, stats.getQueryCacheMissCount() );
+		assertEquals( 1, stats.getQueryCachePutCount() );
+		// the first time the query executes, stats.getSecondLevelCacheHitCount() is 0 because the
+		// entities are read from the query ResultSet (not from the entity cache).
+		assertEquals( 0, stats.getSecondLevelCacheHitCount() );
+		assertEquals( 0, stats.getSecondLevelCacheMissCount() );
+		assertEquals( 0, stats.getSecondLevelCachePutCount() );
+
+		em.getTransaction().commit();
+		em.close();
+
+		stats.clear();
+
+		// Second time the query is executed, list of entities are read from query cache and
+		// the entities themselves are read from the entity cache.
+
+		em = getOrCreateEntityManager();
+		em.getTransaction().begin();
+		query = em.createQuery( "select e from Employee e", Employee.class )
+				.setHint( QueryHints.HINT_CACHEABLE, true );
+		employees = query.getResultList();
+		assertEquals( 10, employees.size() );
+		assertEquals( 1, stats.getQueryCacheHitCount() );
+		assertEquals( 0, stats.getQueryCacheMissCount() );
+		assertEquals( 0, stats.getQueryCachePutCount() );
+		// the first time the query executes, stats.getSecondLevelCacheHitCount() is 0 because the
+		// entities are read from the query ResultSet (not from the entity cache).
+		assertEquals( 10, stats.getSecondLevelCacheHitCount() );
+		assertEquals( 0, stats.getSecondLevelCacheMissCount() );
+		assertEquals( 0, stats.getSecondLevelCachePutCount() );
+
+		em.getTransaction().commit();
+		em.close();
+
+		// NOTE: JPACache.evictAll() only evicts entity regions;
+		//       it does not evict the collection regions or query cache region
+		entityManagerFactory().getCache().evictAll();
+
+		stats.clear();
+
+		em = getOrCreateEntityManager();
+		em.getTransaction().begin();
+		query = em.createQuery( "select e from Employee e", Employee.class )
+				.setHint( QueryHints.HINT_CACHEABLE, true );
+		employees = query.getResultList();
+		assertEquals( 10, employees.size() );
+		// query is still found in the cache
+		assertEquals( 1, stats.getQueryCacheHitCount() );
+		assertEquals( 0, stats.getQueryCacheMissCount() );
+		assertEquals( 0, stats.getQueryCachePutCount() );
+		// since entity regions were evicted, the 10 entities are not found, and are re-put after loading
+		// as each entity ID is read from the query cache, Hibernate will look the entity up in the
+		// cache and will not find it; that's why the "miss" and "put" counts are both 10.
+		assertEquals( 0, stats.getSecondLevelCacheHitCount() );
+		assertEquals( 10, stats.getSecondLevelCacheMissCount() );
+		assertEquals( 10, stats.getSecondLevelCachePutCount() );
+
+		em.getTransaction().commit();
+		em.close();
+
+		stats.clear();
+
+		// this time call clear the entity regions and the query cache region
+		em = getOrCreateEntityManager();
+
+		em.getEntityManagerFactory().getCache().evictAll();
+		em.unwrap( HibernateEntityManagerImplementor.class )
+				.getFactory()
+				.getSessionFactory()
+				.getCache()
+				.evictQueryRegions();
+
+		em.getTransaction().begin();
+		query = em.createQuery( "select e from Employee e", Employee.class )
+				.setHint( QueryHints.HINT_CACHEABLE, true );
+		employees = query.getResultList();
+		assertEquals( 10, employees.size() );
+		// query is no longer found in the cache
+		assertEquals( 0, stats.getQueryCacheHitCount() );
+		assertEquals( 1, stats.getQueryCacheMissCount() );
+		assertEquals( 1, stats.getQueryCachePutCount() );
+		// stats.getSecondLevelCacheHitCount() is 0 because the
+		// entities are read from the query ResultSet (not from the entity cache).
+		assertEquals( 0, stats.getSecondLevelCacheHitCount() );
+		assertEquals( 0, stats.getSecondLevelCacheMissCount() );
+		assertEquals( 10, stats.getSecondLevelCachePutCount() );
+
+		em.createQuery( "delete from Employee" ).executeUpdate();
+		em.getTransaction().commit();
+		em.close();
+	}
+
+	protected void addConfigOptions(Map options) {
+		options.put( AvailableSettings.SHARED_CACHE_MODE, SharedCacheMode.ALL );
+		options.put( Environment.GENERATE_STATISTICS, "true" );
+		options.put( Environment.USE_QUERY_CACHE, "true" );
+		options.put( Environment.USE_SECOND_LEVEL_CACHE, "true" );
+	}
+
+	@Override
+	public Class[] getAnnotatedClasses() {
+		return new Class[]{
+				Employee.class
+		};
+	}
+
+}