HHH-18976 Replace unnecessary dynamic array instantiations with calls to new Object[]

yrodiere · yrodiere · commit f2f5c64e6454 · 2025-01-06T09:05:36.000+01:00
The dynamic instantiations were originally introduced to fix
the following issues:

* HHH-16466 (initial support for array parameters in multi-key loads) --
  tested in MultiLoadTest
* HHH-16750 -- tested in CompositeIdWithOneFieldAndElementCollectionBatchingTest

The corresponding tests still pass after removing these dynamic array
instantiations.
diff --git a/hibernate-core/src/main/java/org/hibernate/loader/ast/internal/AbstractCollectionBatchLoader.java b/hibernate-core/src/main/java/org/hibernate/loader/ast/internal/AbstractCollectionBatchLoader.java
@@ -11,16 +11,10 @@
 import org.hibernate.engine.spi.PersistenceContext;
 import org.hibernate.engine.spi.SessionFactoryImplementor;
 import org.hibernate.engine.spi.SharedSessionContractImplementor;
-import org.hibernate.internal.build.AllowReflection;
 import org.hibernate.loader.ast.spi.CollectionBatchLoader;
-import org.hibernate.metamodel.mapping.NonAggregatedIdentifierMapping;
 import org.hibernate.metamodel.mapping.PluralAttributeMapping;
-import org.hibernate.metamodel.mapping.ValuedModelPart;
-import org.hibernate.metamodel.mapping.internal.IdClassEmbeddable;
 import org.hibernate.sql.results.internal.ResultsHelper;
 
-import java.lang.reflect.Array;
-
 import static org.hibernate.loader.ast.internal.MultiKeyLoadHelper.hasSingleId;
 import static org.hibernate.loader.ast.internal.MultiKeyLoadHelper.trimIdBatch;
 import static org.hibernate.loader.ast.internal.MultiKeyLoadLogging.MULTI_KEY_LOAD_LOGGER;
@@ -127,13 +121,9 @@ protected void finishInitializingKey(Object key, SharedSessionContractImplemento
 
 	}
 
-	@AllowReflection
 	Object[] resolveKeysToInitialize(Object keyBeingLoaded, SharedSessionContractImplementor session) {
 		final int length = getDomainBatchSize();
-		final Object[] keysToInitialize = (Object[]) Array.newInstance(
-				getKeyType( getLoadable().getKeyDescriptor().getKeyPart() ),
-				length
-		);
+		final Object[] keysToInitialize = new Object[length];
 		session.getPersistenceContextInternal().getBatchFetchQueue()
 				.collectBatchLoadableCollectionKeys(
 						length,
@@ -145,15 +135,5 @@ Object[] resolveKeysToInitialize(Object keyBeingLoaded, SharedSessionContractImp
 		return trimIdBatch( length, keysToInitialize );
 	}
 
-	protected Class<?> getKeyType(ValuedModelPart keyPart) {
-		if ( keyPart instanceof NonAggregatedIdentifierMapping ) {
-			final IdClassEmbeddable idClassEmbeddable = ( (NonAggregatedIdentifierMapping) keyPart ).getIdClassEmbeddable();
-			if ( idClassEmbeddable != null ) {
-				return idClassEmbeddable.getMappedJavaType().getJavaTypeClass();
-			}
-		}
-		return keyPart.getJavaType().getJavaTypeClass();
-	}
-
 
 }
diff --git a/hibernate-core/src/main/java/org/hibernate/loader/ast/internal/AbstractMultiIdEntityLoader.java b/hibernate-core/src/main/java/org/hibernate/loader/ast/internal/AbstractMultiIdEntityLoader.java
@@ -11,7 +11,6 @@
 import org.hibernate.engine.spi.EntityKey;
 import org.hibernate.engine.spi.SessionFactoryImplementor;
 import org.hibernate.event.spi.EventSource;
-import org.hibernate.internal.build.AllowReflection;
 import org.hibernate.loader.ast.spi.MultiIdEntityLoader;
 import org.hibernate.loader.ast.spi.MultiIdLoadOptions;
 import org.hibernate.loader.internal.CacheLoadHelper.PersistenceContextEntry;
@@ -22,7 +21,6 @@
 import org.hibernate.sql.exec.spi.JdbcSelectExecutor;
 import org.hibernate.type.descriptor.java.JavaType;
 
-import java.lang.reflect.Array;
 import java.util.ArrayList;
 import java.util.List;
 
@@ -40,15 +38,12 @@
 public abstract class AbstractMultiIdEntityLoader<T> implements MultiIdEntityLoader<T> {
 	private final EntityMappingType entityDescriptor;
 	private final SessionFactoryImplementor sessionFactory;
-	private final EntityIdentifierMapping identifierMapping;
-	protected final Object[] idArray;
+	protected final EntityIdentifierMapping identifierMapping;
 
-	@AllowReflection
 	public AbstractMultiIdEntityLoader(EntityMappingType entityDescriptor, SessionFactoryImplementor sessionFactory) {
 		this.entityDescriptor = entityDescriptor;
 		this.sessionFactory = sessionFactory;
 		identifierMapping = getLoadable().getIdentifierMapping();
-		idArray = (Object[]) Array.newInstance( identifierMapping.getJavaType().getJavaTypeClass(), 0 );
 	}
 
 	protected EntityMappingType getEntityDescriptor() {
@@ -303,7 +298,7 @@ else if ( unresolvedIds.size() == ids.length ) {
 		}
 		else {
 			// we need to load only some the ids
-			return unresolvedIds.toArray( idArray );
+			return unresolvedIds.toArray( new Object[0] );
 		}
 	}
 
diff --git a/hibernate-core/src/main/java/org/hibernate/loader/ast/internal/CollectionBatchLoaderArrayParam.java b/hibernate-core/src/main/java/org/hibernate/loader/ast/internal/CollectionBatchLoaderArrayParam.java
@@ -4,16 +4,13 @@
  */
 package org.hibernate.loader.ast.internal;
 
-import java.lang.reflect.Array;
-
 import org.hibernate.LockOptions;
 import org.hibernate.collection.spi.PersistentCollection;
 import org.hibernate.engine.spi.CollectionKey;
 import org.hibernate.engine.spi.LoadQueryInfluencers;
 import org.hibernate.engine.spi.SessionFactoryImplementor;
 import org.hibernate.engine.spi.SharedSessionContractImplementor;
 import org.hibernate.engine.spi.SubselectFetch;
-import org.hibernate.internal.build.AllowReflection;
 import org.hibernate.loader.ast.spi.CollectionBatchLoader;
 import org.hibernate.loader.ast.spi.SqlArrayMultiKeyLoader;
 import org.hibernate.metamodel.mapping.ForeignKeyDescriptor;
@@ -45,7 +42,6 @@
 public class CollectionBatchLoaderArrayParam
 		extends AbstractCollectionBatchLoader
 		implements SqlArrayMultiKeyLoader {
-	private final Class<?> keyDomainType;
 	private final JdbcMapping arrayJdbcMapping;
 	private final JdbcParameter jdbcParameter;
 	private final SelectStatement sqlSelect;
@@ -69,7 +65,6 @@ public CollectionBatchLoaderArrayParam(
 		final ForeignKeyDescriptor keyDescriptor = getLoadable().getKeyDescriptor();
 		final JdbcMapping jdbcMapping = keyDescriptor.getSingleJdbcMapping();
 		final Class<?> jdbcJavaTypeClass = jdbcMapping.getJdbcJavaType().getJavaTypeClass();
-		keyDomainType = getKeyType( keyDescriptor.getKeyPart() );
 
 		arrayJdbcMapping = MultiKeyLoadHelper.resolveArrayJdbcMapping(
 				jdbcMapping,
@@ -110,7 +105,6 @@ public PersistentCollection<?> load(Object keyBeingLoaded, SharedSessionContract
 
 	}
 
-	@AllowReflection
 	private PersistentCollection<?> loadEmbeddable(
 			Object keyBeingLoaded,
 			SharedSessionContractImplementor session,
@@ -123,15 +117,8 @@ private PersistentCollection<?> loadEmbeddable(
 		}
 
 		final int length = getDomainBatchSize();
-		final Object[] keysToInitialize = (Object[]) Array.newInstance(
-				jdbcParameter.getExpressionType()
-						.getSingleJdbcMapping()
-						.getJdbcJavaType()
-						.getJavaTypeClass()
-						.getComponentType(),
-				length
-		);
-		final Object[] embeddedKeys = (Object[]) Array.newInstance( keyDomainType, length );
+		final Object[] keysToInitialize = new Object[length];
+		final Object[] embeddedKeys = new Object[length];
 		session.getPersistenceContextInternal().getBatchFetchQueue()
 				.collectBatchLoadableCollectionKeys(
 						length,
@@ -212,13 +199,12 @@ void finishInitializingKeys(Object[] keys, SharedSessionContractImplementor sess
 	}
 
 	@Override
-	@AllowReflection
 	Object[] resolveKeysToInitialize(Object keyBeingLoaded, SharedSessionContractImplementor session) {
 		final ForeignKeyDescriptor keyDescriptor = getLoadable().getKeyDescriptor();
 		if( keyDescriptor.isEmbedded()){
 			assert keyDescriptor.getJdbcTypeCount() == 1;
 			final int length = getDomainBatchSize();
-			final Object[] keysToInitialize = (Object[]) Array.newInstance( keyDescriptor.getSingleJdbcMapping().getJdbcJavaType().getJavaTypeClass(), length );
+			final Object[] keysToInitialize = new Object[length];
 			session.getPersistenceContextInternal().getBatchFetchQueue()
 					.collectBatchLoadableCollectionKeys(
 							length,
diff --git a/hibernate-core/src/main/java/org/hibernate/loader/ast/internal/EntityBatchLoaderArrayParam.java b/hibernate-core/src/main/java/org/hibernate/loader/ast/internal/EntityBatchLoaderArrayParam.java
@@ -4,14 +4,12 @@
  */
 package org.hibernate.loader.ast.internal;
 
-import java.lang.reflect.Array;
 import java.util.Arrays;
 import java.util.Locale;
 
 import org.hibernate.LockOptions;
 import org.hibernate.engine.spi.LoadQueryInfluencers;
 import org.hibernate.engine.spi.SharedSessionContractImplementor;
-import org.hibernate.internal.build.AllowReflection;
 import org.hibernate.loader.ast.spi.SqlArrayMultiKeyLoader;
 import org.hibernate.metamodel.mapping.BasicEntityIdentifierMapping;
 import org.hibernate.metamodel.mapping.EntityIdentifierMapping;
@@ -105,11 +103,9 @@ public int getDomainBatchSize() {
 		return domainBatchSize;
 	}
 
-	@AllowReflection
 	protected Object[] resolveIdsToInitialize(Object pkValue, SharedSessionContractImplementor session) {
 		//TODO: should this really be different to EntityBatchLoaderInPredicate impl?
-		final Class<?> idType = identifierMapping.getJavaType().getJavaTypeClass();
-		final Object[] idsToLoad = (Object[]) Array.newInstance( idType, domainBatchSize );
+		final Object[] idsToLoad = new Object[domainBatchSize];
 		session.getPersistenceContextInternal().getBatchFetchQueue()
 				.collectBatchLoadableEntityIds(
 						domainBatchSize,
diff --git a/hibernate-core/src/main/java/org/hibernate/loader/ast/internal/MultiIdEntityLoaderArrayParam.java b/hibernate-core/src/main/java/org/hibernate/loader/ast/internal/MultiIdEntityLoaderArrayParam.java
@@ -49,10 +49,9 @@ public MultiIdEntityLoaderArrayParam(
 			EntityMappingType entityDescriptor,
 			SessionFactoryImplementor sessionFactory) {
 		super( entityDescriptor, sessionFactory );
-		final Class<?> idClass = idArray.getClass().getComponentType();
 		arrayJdbcMapping = resolveArrayJdbcMapping(
 				getIdentifierMapping().getJdbcMapping(),
-				idClass,
+				identifierMapping.getJavaType().getJavaTypeClass(),
 				getSessionFactory()
 		);
 		jdbcParameter = new JdbcParameterImpl( arrayJdbcMapping );
@@ -117,7 +116,7 @@ protected void loadEntitiesById(
 
 		final JdbcParameterBindings jdbcParameterBindings = new JdbcParameterBindingsImpl(1);
 		jdbcParameterBindings.addBinding( jdbcParameter,
-				new JdbcParameterBindingImpl( arrayJdbcMapping, idsInBatch.toArray( idArray ) ) );
+				new JdbcParameterBindingImpl( arrayJdbcMapping, idsInBatch ) );
 
 		getJdbcSelectExecutor().executeQuery(
 				getSqlAstTranslatorFactory().buildSelectTranslator( getSessionFactory(), sqlAst )
