HHH-8276 - Integrate LoadPlans into UniqueEntityLoader (PoC) - Initial reworking to remove SQL references (for reuse in Search, OGM, etc) and to split out conceptual "from clause" and "select clause" into different structures (see QuerySpaces)

Author: sebersole

hibernate-core/src/main/java/org/hibernate/loader/entity/plan/AbstractLoadPlanBasedEntityLoader.java

@@ -32,12 +32,11 @@
 import org.hibernate.loader.entity.UniqueEntityLoader;
 import org.hibernate.loader.plan.exec.query.spi.NamedParameterContext;
 import org.hibernate.loader.plan.exec.query.spi.QueryBuildingParameters;
-import org.hibernate.loader.plan.exec.spi.LoadQueryDetails;
+import org.hibernate.loader.plan.exec.spi.EntityLoadQueryDetails;
 import org.hibernate.loader.plan.internal.SingleRootReturnLoadPlanBuilderStrategy;
 import org.hibernate.loader.plan.spi.LoadPlan;
-import org.hibernate.loader.plan.spi.build.LoadPlanBuilder;
+import org.hibernate.loader.plan.spi.build.MetadataDrivenLoadPlanBuilder;
 import org.hibernate.loader.spi.AfterLoadAction;
-import org.hibernate.loader.spi.NoOpLoadPlanAdvisor;
 import org.hibernate.persister.entity.EntityPersister;
 import org.hibernate.persister.entity.OuterJoinLoadable;
 import org.hibernate.pretty.MessageHelper;
@@ -58,7 +57,7 @@ public abstract class AbstractLoadPlanBasedEntityLoader implements UniqueEntityL
 	private final String entityName;
 
 	private final LoadPlan plan;
-	private final LoadQueryDetails staticLoadQuery;
+	private final EntityLoadQueryDetails staticLoadQuery;
 
 	private ColumnNameCache columnNameCache;
 
@@ -78,20 +77,20 @@ public AbstractLoadPlanBasedEntityLoader(
 				buildingParameters.getQueryInfluencers()
 		);
 
-		this.plan = LoadPlanBuilder.buildRootEntityLoadPlan( strategy, entityPersister );
-		this.staticLoadQuery = LoadQueryDetails.makeForBatching(
-				uniqueKeyColumnNames,
+		this.plan = MetadataDrivenLoadPlanBuilder.buildRootEntityLoadPlan( strategy, entityPersister );
+		this.staticLoadQuery = EntityLoadQueryDetails.makeForBatching(
 				plan,
-				factory,
-				buildingParameters
+				uniqueKeyColumnNames,
+				buildingParameters,
+				factory
 		);
 	}
 
 	protected SessionFactoryImplementor getFactory() {
 		return factory;
 	}
 
-	protected LoadQueryDetails getStaticLoadQuery() {
+	protected EntityLoadQueryDetails getStaticLoadQuery() {
 		return staticLoadQuery;
 	}
 
@@ -197,7 +196,7 @@ public Object load(Serializable id, Object optionalObject, SessionImplementor se
 	protected List executeLoad(
 			SessionImplementor session,
 			QueryParameters queryParameters,
-			LoadQueryDetails loadQueryDetails,
+			EntityLoadQueryDetails loadQueryDetails,
 			boolean returnProxies,
 			ResultTransformer forcedResultTransformer) throws SQLException {
 		final List<AfterLoadAction> afterLoadActions = new ArrayList<AfterLoadAction>();
@@ -214,7 +213,7 @@ protected List executeLoad(
 	protected List executeLoad(
 			SessionImplementor session,
 			QueryParameters queryParameters,
-			LoadQueryDetails loadQueryDetails,
+			EntityLoadQueryDetails loadQueryDetails,
 			boolean returnProxies,
 			ResultTransformer forcedResultTransformer,
 			List<AfterLoadAction> afterLoadActions) throws SQLException {
@@ -237,8 +236,6 @@ protected List executeLoad(
 			try {
 				final SqlStatementWrapper wrapper = executeQueryStatement( sql, queryParameters, false, afterLoadActions, session );
 				results = loadQueryDetails.getResultSetProcessor().extractResults(
-						// todo : hook in the JPA 2.1 entity graph advisor
-						NoOpLoadPlanAdvisor.INSTANCE,
 						wrapper.getResultSet(),
 						session,
 						queryParameters,
@@ -248,7 +245,6 @@ public int[] getNamedParameterLocations(String name) {
 								return AbstractLoadPlanBasedEntityLoader.this.getNamedParameterLocs( name );
 							}
 						},
-						loadQueryDetails.getAliasResolutionContext(),
 						returnProxies,
 						queryParameters.isReadOnly(),
 						forcedResultTransformer,
@@ -295,7 +291,7 @@ else if ( results.size() == 1 ) {
 	protected Object doQueryAndLoadEntity(
 			SessionImplementor session,
 			QueryParameters queryParameters,
-			LoadQueryDetails loadQueryDetails,
+			EntityLoadQueryDetails loadQueryDetails,
 			boolean returnProxies,
 			ResultTransformer forcedResultTransformer) throws SQLException {
 
@@ -305,7 +301,6 @@ protected Object doQueryAndLoadEntity(
 
 		try {
 			final List results = loadQueryDetails.getResultSetProcessor().extractResults(
-					NoOpLoadPlanAdvisor.INSTANCE,
 					wrapper.getResultSet(),
 					session,
 					queryParameters,
@@ -315,7 +310,6 @@ public int[] getNamedParameterLocations(String name) {
 							return AbstractLoadPlanBasedEntityLoader.this.getNamedParameterLocs( name );
 						}
 					},
-					loadQueryDetails.getAliasResolutionContext(),
 					returnProxies,
 					queryParameters.isReadOnly(),
 					forcedResultTransformer,

hibernate-core/src/main/java/org/hibernate/loader/plan/exec/internal/Helper.java

@@ -0,0 +1,79 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * Copyright (c) 2013, 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.loader.plan.exec.internal;
+
+import org.hibernate.loader.plan.spi.LoadPlan;
+import org.hibernate.loader.plan.spi.Return;
+
+/**
+ * @author Steve Ebersole
+ */
+public class Helper {
+	/**
+	 * Singleton access
+	 */
+	public static final Helper INSTANCE = new Helper();
+
+	/**
+	 * Disallow direct instantiation
+	 */
+	private Helper() {
+	}
+
+
+	/**
+	 * Extract the root return of the LoadPlan, assuming there is just one.
+	 *
+	 * @param loadPlan The LoadPlan from which to extract the root return
+	 * @param returnType The Return type expected, passed as an argument
+	 * @param <T> The parameterized type of the specific Return type expected
+	 *
+	 * @return The root Return
+	 *
+	 * @throws IllegalStateException If there is no root, more than one root or the single root
+	 * is not of the expected type.
+	 */
+	@SuppressWarnings("unchecked")
+	public <T extends Return> T extractRootReturn(LoadPlan loadPlan, Class<T> returnType) {
+		if ( loadPlan.getReturns().size() == 0 ) {
+			throw new IllegalStateException( "LoadPlan contained no root returns" );
+		}
+		else if ( loadPlan.getReturns().size() > 1 ) {
+			throw new IllegalStateException( "LoadPlan contained more than one root returns" );
+		}
+
+		final Return rootReturn = loadPlan.getReturns().get( 0 );
+		if ( !returnType.isInstance( rootReturn ) ) {
+			throw new IllegalStateException(
+					String.format(
+							"Unexpected LoadPlan root return; expecting %s, but found %s",
+							returnType.getName(),
+							rootReturn.getClass().getName()
+					)
+			);
+		}
+
+		return (T) rootReturn;
+	}
+}