HHH-15789 make IdentifierGenerator into a sort of value generator

hibernate-core/src/main/java/org/hibernate/annotations/SourceGeneration.java

@@ -79,8 +79,8 @@ public class SourceGeneration
 	}
 
 	@Override
-	public ValueGenerator<?> getValueGenerator() {
+	public Object generate(SharedSessionContractImplementor session, Object owner, Object currentValue) {
-		return valueGenerator;
+		return valueGenerator.generateValue( (Session) session, owner, currentValue );
 	}
 
 	@Override

hibernate-core/src/main/java/org/hibernate/id/CompositeNestedGeneratedValueGenerator.java

@@ -9,7 +9,6 @@ package org.hibernate.id;
 import java.io.Serializable;
 import java.util.ArrayList;
 import java.util.List;
-import java.util.Properties;
 
 import org.hibernate.HibernateException;
 import org.hibernate.boot.model.relational.Database;
@@ -17,8 +16,6 @@ import org.hibernate.boot.model.relational.ExportableProducer;
 import org.hibernate.boot.model.relational.SqlStringGenerationContext;
 import org.hibernate.engine.spi.SharedSessionContractImplementor;
 import org.hibernate.id.factory.spi.StandardGenerator;
-import org.hibernate.service.ServiceRegistry;
-import org.hibernate.type.Type;
 
 /**
  * For composite identifiers, defines a number of "nested" generations that

hibernate-core/src/main/java/org/hibernate/id/IdentifierGenerator.java

@@ -7,7 +7,6 @@
 package org.hibernate.id;
 
 import java.util.Properties;
-import jakarta.persistence.GeneratedValue;
 
 import org.hibernate.HibernateException;
 import org.hibernate.MappingException;
@@ -16,19 +15,23 @@ import org.hibernate.boot.model.relational.ExportableProducer;
 import org.hibernate.boot.model.relational.SqlStringGenerationContext;
 import org.hibernate.engine.spi.SharedSessionContractImplementor;
 import org.hibernate.service.ServiceRegistry;
+import org.hibernate.tuple.GenerationTiming;
+import org.hibernate.tuple.InMemoryValueGenerationStrategy;
 import org.hibernate.type.Type;
 
+import static org.hibernate.tuple.GenerationTiming.INSERT;
+
 /**
  * The general contract between a class that generates unique
- * identifiers and the {@code Session}. It is not intended that
+ * identifiers and the {@link org.hibernate.Session}. It is not
- * this interface ever be exposed to the application. It <b>is</b>
+ * intended that this interface ever be exposed to the application.
- * intended that users implement this interface to provide
+ * It <em>is</em> intended that users implement this interface to
- * custom identifier generation strategies.
+ * provide custom identifier generation strategies.
  * <p>
  * Implementors should provide a public default constructor.
  * <p>
- * Implementations that accept configuration parameters should
+ * Implementations that accept configuration parameters should also
- * also implement {@code Configurable}.
+ * implement {@link Configurable}.
  * <p>
  * Implementors <em>must</em> be thread-safe
  *
@@ -36,7 +39,7 @@ import org.hibernate.type.Type;
  *
  * @see PersistentIdentifierGenerator
  */
-public interface IdentifierGenerator extends Configurable, ExportableProducer {
+public interface IdentifierGenerator extends InMemoryValueGenerationStrategy, ExportableProducer, Configurable {
 	/**
 	 * The configuration parameter holding the entity name
 	 */
@@ -48,8 +51,11 @@ public interface IdentifierGenerator extends Configurable, ExportableProducer {
 	String JPA_ENTITY_NAME = "jpa_entity_name";
 
 	/**
-	 * Used as a key to pass the name used as {@link GeneratedValue#generator()} to  the
+	 * The configuration parameter holding the name of this
-	 * {@link IdentifierGenerator} as it is configured.
+	 * identifier generator.
+	 *
+	 * @see org.hibernate.annotations.GenericGenerator#name()
+	 * @see jakarta.persistence.GeneratedValue#generator().
 	 */
 	String GENERATOR_NAME = "GENERATOR_NAME";
 
@@ -62,7 +68,8 @@ public interface IdentifierGenerator extends Configurable, ExportableProducer {
 	 * Configure this instance, given the value of parameters
 	 * specified by the user as {@code &lt;param&gt;} elements.
 	 * <p>
-	 * This method is called just once, following instantiation, and before {@link #registerExportables(Database)}.
+	 * This method is called just once, following instantiation,
+	 * and before {@link #registerExportables(Database)}.
 	 *
 	 * @param type The id property type descriptor
 	 * @param params param values, keyed by parameter name
@@ -70,13 +77,15 @@ public interface IdentifierGenerator extends Configurable, ExportableProducer {
 	 * @throws MappingException If configuration fails.
 	 */
 	@Override
-	default void configure(Type type, Properties params, ServiceRegistry serviceRegistry) throws MappingException {
+	default void configure(Type type, Properties params, ServiceRegistry serviceRegistry) {
 	}
 
 	/**
-	 * Register database objects used by this identifier generator, e.g. sequences, tables, etc.
+	 * Register database objects used by this identifier generator,
+	 * for example, a sequence or tables.
 	 * <p>
-	 * This method is called just once, after {@link #configure(Type, Properties, ServiceRegistry)}.
+	 * This method is called just once, after
+	 * {@link #configure(Type, Properties, ServiceRegistry)}.
 	 *
 	 * @param database The database instance
 	 */
@@ -85,9 +94,12 @@ public interface IdentifierGenerator extends Configurable, ExportableProducer {
 	}
 
 	/**
-	 * Initializes this instance, in particular pre-generates SQL as necessary.
+	 * Initializes this instance, in particular pre-generates
+	 * SQL as necessary.
 	 * <p>
-	 * This method is called after {@link #registerExportables(Database)}, before first use.
+	 * This method is called after
+	 * {@link #registerExportables(Database)},
+	 * and before first use.
 	 *
 	 * @param context A context to help generate SQL strings
 	 */
@@ -104,13 +116,26 @@ public interface IdentifierGenerator extends Configurable, ExportableProducer {
 	 *
 	 * @throws HibernateException Indicates trouble generating the identifier
 	 */
-	Object generate(SharedSessionContractImplementor session, Object object) throws HibernateException;
+	Object generate(SharedSessionContractImplementor session, Object object);
+
+	@Override
+	default Object generate(SharedSessionContractImplementor session, Object owner, Object currentValue) {
+		return generate( session, owner );
+	}
+
+	@Override
+	default GenerationTiming getGenerationTiming() {
+		return INSERT;
+	}
 
 	/**
 	 * Check if JDBC batch inserts are supported.
 	 *
 	 * @return JDBC batch inserts are supported.
+	 *
+	 * @deprecated this method is no longer called
 	 */
+	@Deprecated(since="6.2")
 	default boolean supportsJdbcBatchInserts() {
 		return true;
 	}

hibernate-core/src/main/java/org/hibernate/id/PersistentIdentifierGenerator.java

@@ -8,16 +8,14 @@ package org.hibernate.id;
 
 import java.util.Properties;
 
-import org.hibernate.HibernateException;
-import org.hibernate.dialect.Dialect;
 import org.hibernate.service.ServiceRegistry;
 import org.hibernate.type.Type;
 
 /**
- * An {@code IdentifierGenerator} that requires creation of database objects.
+ * An {@link IdentifierGenerator} that requires creation of database objects.
  * <p>
- * All {@code PersistentIdentifierGenerator}s have access to a special mapping parameter
+ * All instances have access to a special mapping parameter in their
- * in their {@link #configure(Type, Properties, ServiceRegistry)} method: schema
+ * {@link #configure(Type, Properties, ServiceRegistry)} method: schema
  *
  * @author Gavin King
  * @author Steve Ebersole

hibernate-core/src/main/java/org/hibernate/metamodel/mapping/GeneratedValueResolver.java

@@ -40,10 +40,10 @@ public interface GeneratedValueResolver {
 		}
 		else {
 			InMemoryValueGenerationStrategy generation = (InMemoryValueGenerationStrategy) valueGeneration;
-			return new InMemoryGeneratedValueResolver( generation.getValueGenerator(), requestedTiming );
+			return new InMemoryGeneratedValueResolver( generation, requestedTiming );
 		}
 	}
 
 	GenerationTiming getGenerationTiming();
-	Object resolveGeneratedValue(Object[] row, Object entity, SharedSessionContractImplementor session);
+	Object resolveGeneratedValue(Object[] row, Object entity, SharedSessionContractImplementor session, Object currentValue);
 }

hibernate-core/src/main/java/org/hibernate/metamodel/mapping/InDatabaseGeneratedValueResolver.java

@@ -32,7 +32,7 @@ public class InDatabaseGeneratedValueResolver implements GeneratedValueResolver
 	}
 
 	@Override
-	public Object resolveGeneratedValue(Object[] row, Object entity, SharedSessionContractImplementor session) {
+	public Object resolveGeneratedValue(Object[] row, Object entity, SharedSessionContractImplementor session, Object currentValue) {
 		return row[resultPosition];
 	}
 }

hibernate-core/src/main/java/org/hibernate/metamodel/mapping/InMemoryGeneratedValueResolver.java

@@ -7,10 +7,9 @@
 package org.hibernate.metamodel.mapping;
 
 import org.hibernate.Internal;
-import org.hibernate.Session;
 import org.hibernate.engine.spi.SharedSessionContractImplementor;
 import org.hibernate.tuple.GenerationTiming;
-import org.hibernate.tuple.ValueGenerator;
+import org.hibernate.tuple.InMemoryValueGenerationStrategy;
 
 /**
  * GeneratedValueResolver impl for in-memory generation
@@ -20,9 +19,9 @@ import org.hibernate.tuple.ValueGenerator;
 @Internal
 public class InMemoryGeneratedValueResolver implements GeneratedValueResolver {
 	private final GenerationTiming generationTiming;
-	private final ValueGenerator valueGenerator;
+	private final InMemoryValueGenerationStrategy valueGenerator;
 
-	public InMemoryGeneratedValueResolver(ValueGenerator valueGenerator, GenerationTiming generationTiming) {
+	public InMemoryGeneratedValueResolver(InMemoryValueGenerationStrategy valueGenerator, GenerationTiming generationTiming) {
 		this.valueGenerator = valueGenerator;
 		this.generationTiming = generationTiming;
 	}
@@ -33,7 +32,7 @@ public class InMemoryGeneratedValueResolver implements GeneratedValueResolver {
 	}
 
 	@Override
-	public Object resolveGeneratedValue(Object[] row, Object entity, SharedSessionContractImplementor session) {
+	public Object resolveGeneratedValue(Object[] row, Object entity, SharedSessionContractImplementor session, Object currentValue) {
-		return valueGenerator.generateValue( (Session) session, entity );
+		return valueGenerator.generate( session, entity, currentValue );
 	}
 }

hibernate-core/src/main/java/org/hibernate/metamodel/mapping/internal/GeneratedValuesProcessor.java

@@ -175,7 +175,7 @@ public class GeneratedValuesProcessor {
 
 		for ( int i = 0; i < valueDescriptors.size(); i++ ) {
 			final GeneratedValueDescriptor descriptor = valueDescriptors.get( i );
-			final Object generatedValue = descriptor.resolver.resolveGeneratedValue( dbSelectionResults, entity, session );
+			final Object generatedValue = descriptor.resolver.resolveGeneratedValue( dbSelectionResults, entity, session, state[i] );
 			state[ descriptor.attribute.getStateArrayPosition() ] = generatedValue;
 			descriptor.attribute.getAttributeMetadataAccess()
 					.resolveAttributeMetadata( entityDescriptor )

hibernate-core/src/main/java/org/hibernate/metamodel/mapping/internal/NoGeneratedValueResolver.java

@@ -26,7 +26,7 @@ public class NoGeneratedValueResolver implements GeneratedValueResolver {
 	}
 
 	@Override
-	public Object resolveGeneratedValue(Object[] row, Object entity, SharedSessionContractImplementor session) {
+	public Object resolveGeneratedValue(Object[] row, Object entity, SharedSessionContractImplementor session, Object currentValue) {
 		throw new UnsupportedMappingException( "NoGeneratedValueResolver does not support generated values" );
 	}
 }

hibernate-core/src/main/java/org/hibernate/persister/entity/mutation/InsertCoordinator.java

@@ -10,7 +10,6 @@ import java.util.ArrayList;
 import java.util.List;
 
 import org.hibernate.Internal;
-import org.hibernate.Session;
 import org.hibernate.engine.jdbc.batch.internal.BasicBatchKey;
 import org.hibernate.engine.jdbc.mutation.JdbcValueBindings;
 import org.hibernate.engine.jdbc.mutation.MutationExecutor;
@@ -104,7 +103,7 @@ public class InsertCoordinator extends AbstractMutationCoordinator {
 			final InMemoryValueGenerationStrategy[] strategies = entityMetamodel.getInMemoryValueGenerationStrategies();
 			for ( int i = 0; i < strategies.length; i++ ) {
 				if ( strategies[i] != null && strategies[i].getGenerationTiming().includesInsert() ) {
-					values[i] = strategies[i].getValueGenerator().generateValue( (Session) session, entity, values[i] );
+					values[i] = strategies[i].generate( session, entity, values[i] );
 					entityPersister().setPropertyValue( entity, i, values[i] );
 				}
 			}

hibernate-core/src/main/java/org/hibernate/persister/entity/mutation/UpdateCoordinatorStandard.java

@@ -14,7 +14,6 @@ import java.util.Set;
 
 import org.hibernate.HibernateException;
 import org.hibernate.Internal;
-import org.hibernate.Session;
 import org.hibernate.engine.OptimisticLockStyle;
 import org.hibernate.engine.jdbc.batch.internal.BasicBatchKey;
 import org.hibernate.engine.jdbc.batch.spi.BatchKey;
@@ -427,10 +426,7 @@ public class UpdateCoordinatorStandard extends AbstractMutationCoordinator imple
 			for ( int i = 0; i < valueGenerationStrategies.length; i++ ) {
 				if ( valueGenerationStrategies[i] != null
 						&& valueGenerationStrategies[i].getGenerationTiming().includesUpdate() ) {
-					newValues[i] = valueGenerationStrategies[i].getValueGenerator().generateValue(
+					newValues[i] = valueGenerationStrategies[i].generate( session, object, newValues[i] );
-							(Session) session,
-							object
-					);
 					entityPersister().setPropertyValue( object, i, newValues[i] );
 					fieldsPreUpdateNeeded[count++] = i;
 				}

hibernate-core/src/main/java/org/hibernate/tuple/InMemoryValueGenerationStrategy.java

@@ -6,6 +6,8 @@
  */
 package org.hibernate.tuple;
 
+import org.hibernate.engine.spi.SharedSessionContractImplementor;
+
 /**
  * Java value generation is the responsibility of an associated {@link ValueGenerator}.
  * In this case, the generated value is written to the database just like any other field
@@ -16,14 +18,16 @@ package org.hibernate.tuple;
  * @since 6.2
  */
 public interface InMemoryValueGenerationStrategy extends ValueGenerationStrategy {
-
 	/**
-	 * Obtain the {@linkplain ValueGenerator Java value generator}, if the value is generated in
+	 * Generate a value.
-	 * Java, or return {@code null} if the value is generated by the database.
 	 *
-	 * @return The value generator
+	 * @param session The session from which the request originates.
+	 * @param owner The instance of the object owning the attribute for which we are generating a value.
+	 * @param currentValue The current value assigned to the property, or {@code null}
+	 *
+	 * @return The generated value
 	 */
-	ValueGenerator<?> getValueGenerator();
+	Object generate(SharedSessionContractImplementor session, Object owner, Object currentValue);
 
 	default boolean generatedByDatabase() {
 		return false;

hibernate-core/src/main/java/org/hibernate/tuple/TenantIdGeneration.java

@@ -8,10 +8,10 @@ package org.hibernate.tuple;
 
 import org.hibernate.MappingException;
 import org.hibernate.PropertyValueException;
-import org.hibernate.Session;
 import org.hibernate.annotations.TenantId;
 import org.hibernate.context.spi.CurrentTenantIdentifierResolver;
 import org.hibernate.engine.spi.SessionFactoryImplementor;
+import org.hibernate.engine.spi.SharedSessionContractImplementor;
 import org.hibernate.type.descriptor.java.JavaType;
 
 /**
@@ -20,7 +20,7 @@ import org.hibernate.type.descriptor.java.JavaType;
  * @author Gavin King
  */
 public class TenantIdGeneration
-		implements AnnotationValueGenerationStrategy<TenantId>, InMemoryValueGenerationStrategy, ValueGenerator<Object> {
+		implements AnnotationValueGenerationStrategy<TenantId>, InMemoryValueGenerationStrategy {
 
 	private String entityName;
 	private String propertyName;
@@ -39,13 +39,8 @@ public class TenantIdGeneration
 	}
 
 	@Override
-	public ValueGenerator<?> getValueGenerator() {
+	public Object generate(SharedSessionContractImplementor session, Object owner, Object currentValue) {
-		return this;
+		SessionFactoryImplementor sessionFactory = session.getSessionFactory();
-	}
-
-	@Override
-	public Object generateValue(Session session, Object owner, Object currentValue) {
-		SessionFactoryImplementor sessionFactory = (SessionFactoryImplementor) session.getSessionFactory();
 		JavaType<Object> descriptor = sessionFactory.getTypeConfiguration().getJavaTypeRegistry()
 				.findDescriptor(propertyType);
 		if ( descriptor==null ) {
@@ -70,9 +65,4 @@ public class TenantIdGeneration
 		}
 		return tenantId == null ? null : descriptor.fromString(tenantId); //convert to the model type
 	}
-
-	@Override
-	public Object generateValue(Session session, Object owner) {
-		throw new UnsupportedOperationException();
-	}
 }

hibernate-core/src/main/java/org/hibernate/tuple/ValueGeneration.java

@@ -6,7 +6,9 @@
  */
 package org.hibernate.tuple;
 
+import org.hibernate.Session;
 import org.hibernate.dialect.Dialect;
+import org.hibernate.engine.spi.SharedSessionContractImplementor;
 
 /**
  * A value generator that can adapt to both Java value generation and database value
@@ -16,6 +18,19 @@ import org.hibernate.dialect.Dialect;
  * @author Gavin King
  */
 public interface ValueGeneration extends InMemoryValueGenerationStrategy, InDatabaseValueGenerationStrategy {
+	/**
+	 * Obtain the {@linkplain ValueGenerator Java value generator}, if the value is generated in
+	 * Java, or return {@code null} if the value is generated by the database.
+	 *
+	 * @return The value generator
+	 */
+	ValueGenerator<?> getValueGenerator();
+
+	@Override
+	default Object generate(SharedSessionContractImplementor session, Object owner, Object currentValue) {
+		return getValueGenerator().generateValue( (Session) session, owner, currentValue );
+	}
+
 	/**
 	 * Determines if the column whose value is generated is included in the column list of the
 	 * SQL {@code insert} or {@code update} statement, in the case where the value is generated

hibernate-core/src/main/java/org/hibernate/tuple/ValueGenerationStrategy.java

@@ -52,8 +52,9 @@ public interface ValueGenerationStrategy extends Serializable {
 
 	/**
 	 * Determines if the property value is generated in Java, or by the database.
+	 *
 	 * @return {@code true} if the value is generated by the database, or false if it is
-	 *		 generated in Java using a {@link ValueGenerator}.
+	 *		   generated in Java using a {@link ValueGenerator}.
 	 */
 	boolean generatedByDatabase();
 }

hibernate-core/src/main/java/org/hibernate/tuple/ValueGenerator.java

@@ -34,6 +34,6 @@ public interface ValueGenerator<T> {
 	 * @return The generated value
 	 */
 	default T generateValue(Session session, Object owner, Object currentValue) {
-		return generateValue(session, owner);
+		return generateValue( session, owner );
 	}
 }

hibernate-core/src/main/java/org/hibernate/tuple/VmValueGeneration.java

@@ -9,7 +9,9 @@ package org.hibernate.tuple;
 import java.lang.reflect.Constructor;
 
 import org.hibernate.HibernateException;
+import org.hibernate.Session;
 import org.hibernate.annotations.GeneratorType;
+import org.hibernate.engine.spi.SharedSessionContractImplementor;
 import org.hibernate.internal.util.ReflectHelper;
 
 /**
@@ -21,11 +23,17 @@ public class VmValueGeneration
 		implements AnnotationValueGenerationStrategy<GeneratorType>, InMemoryValueGenerationStrategy {
 
 	private GenerationTiming generationTiming;
-	private Constructor<? extends ValueGenerator<?>> constructor;
+	ValueGenerator<?> generator;
 
 	@Override
 	public void initialize(GeneratorType annotation, Class<?> propertyType, String entityName, String propertyName) {
-		constructor = ReflectHelper.getDefaultConstructor( annotation.type() );
+		Constructor<? extends ValueGenerator<?>> constructor = ReflectHelper.getDefaultConstructor(annotation.type());
+		try {
+			generator = constructor.newInstance();
+		}
+		catch (Exception e) {
+			throw new HibernateException( "Couldn't instantiate value generator", e );
+		}
 		generationTiming = annotation.when().getEquivalent();
 	}
 
@@ -35,12 +43,7 @@ public class VmValueGeneration
 	}
 
 	@Override
-	public ValueGenerator<?> getValueGenerator() {
+	public Object generate(SharedSessionContractImplementor session, Object owner, Object currentValue) {
-		try {
+		return generator.generateValue( (Session) session, owner, currentValue );
-			return constructor.newInstance();
-		}
-		catch (Exception e) {
-			throw new HibernateException( "Couldn't instantiate value generator", e );
-		}
 	}
 }

hibernate-core/src/main/java/org/hibernate/tuple/entity/EntityMetamodel.java

@@ -29,6 +29,7 @@ import org.hibernate.engine.spi.CascadeStyle;
 import org.hibernate.engine.spi.CascadeStyles;
 import org.hibernate.engine.spi.CascadingActions;
 import org.hibernate.engine.spi.SessionFactoryImplementor;
+import org.hibernate.engine.spi.SharedSessionContractImplementor;
 import org.hibernate.internal.CoreMessageLogger;
 import org.hibernate.internal.util.ReflectHelper;
 import org.hibernate.internal.util.collections.ArrayHelper;
@@ -47,7 +48,6 @@ import org.hibernate.tuple.IdentifierProperty;
 import org.hibernate.tuple.InMemoryValueGenerationStrategy;
 import org.hibernate.tuple.NonIdentifierAttribute;
 import org.hibernate.tuple.PropertyFactory;
-import org.hibernate.tuple.ValueGenerator;
 import org.hibernate.type.AssociationType;
 import org.hibernate.type.CollectionType;
 import org.hibernate.type.ComponentType;
@@ -304,28 +304,25 @@ public class EntityMetamodel implements Serializable {
 			inMemoryValueGenerationStrategies[i] = pair.getInMemoryStrategy();
 			inDatabaseValueGenerationStrategies[i] = pair.getInDatabaseStrategy();
 
-			if ( pair.getInMemoryStrategy() != null ) {
+			if ( pair.getInMemoryStrategy() != null
+					&& !pair.getInMemoryStrategy().generatedByDatabase() ) {
 				final GenerationTiming timing = pair.getInMemoryStrategy().getGenerationTiming();
-				if ( timing != GenerationTiming.NEVER ) {
+				// we have some level of generation indicated
-					final ValueGenerator<?> generator = pair.getInMemoryStrategy().getValueGenerator();
+				switch ( timing ) {
-					if ( generator != null ) {
+					case INSERT:
-						// we have some level of generation indicated
+						foundPreInsertGeneratedValues = true;
-						switch ( timing ) {
+						break;
-							case INSERT:
+					case UPDATE:
-								foundPreInsertGeneratedValues = true;
+						foundPreUpdateGeneratedValues = true;
-								break;
+						break;
-							case UPDATE:
+					case ALWAYS:
-								foundPreUpdateGeneratedValues = true;
+						foundPreInsertGeneratedValues = true;
-								break;
+						foundPreUpdateGeneratedValues = true;
-							case ALWAYS:
+						break;
-								foundPreInsertGeneratedValues = true;
-								foundPreUpdateGeneratedValues = true;
-								break;
-						}
-					}
 				}
 			}
-			if (  pair.getInDatabaseStrategy() != null ) {
+			if (  pair.getInDatabaseStrategy() != null
+					&& pair.getInDatabaseStrategy().generatedByDatabase() ) {
 				switch ( pair.getInDatabaseStrategy().getGenerationTiming() ) {
 					case INSERT:
 						foundPostInsertGeneratedValues = true;
@@ -463,9 +460,7 @@ public class EntityMetamodel implements Serializable {
 			// the property is generated in full. build the generation strategy pair.
 			if ( !valueGeneration.generatedByDatabase() ) {
 				// in-memory generation
-				return new GenerationStrategyPair(
+				return new GenerationStrategyPair( (InMemoryValueGenerationStrategy) valueGeneration );
-						FullInMemoryValueGenerationStrategy.create( (InMemoryValueGenerationStrategy) valueGeneration )
-				);
 			}
 			else {
 				// in-db generation
@@ -503,7 +498,7 @@ public class EntityMetamodel implements Serializable {
 			this( NoInMemoryValueGenerationStrategy.INSTANCE, NoInDatabaseValueGenerationStrategy.INSTANCE );
 		}
 
-		public GenerationStrategyPair(FullInMemoryValueGenerationStrategy inMemoryStrategy) {
+		public GenerationStrategyPair(InMemoryValueGenerationStrategy inMemoryStrategy) {
 			this( inMemoryStrategy, NoInDatabaseValueGenerationStrategy.INSTANCE );
 		}
 
@@ -685,38 +680,11 @@ public class EntityMetamodel implements Serializable {
 		}
 
 		@Override
-		public ValueGenerator<?> getValueGenerator() {
+		public Object generate(SharedSessionContractImplementor session, Object owner, Object currentValue) {
 			return null;
 		}
 	}
 
-	private static class FullInMemoryValueGenerationStrategy implements InMemoryValueGenerationStrategy {
-		private final GenerationTiming timing;
-		private final ValueGenerator<?> generator;
-
-		private FullInMemoryValueGenerationStrategy(GenerationTiming timing, ValueGenerator<?> generator) {
-			this.timing = timing;
-			this.generator = generator;
-		}
-
-		public static FullInMemoryValueGenerationStrategy create(InMemoryValueGenerationStrategy valueGeneration) {
-			return new FullInMemoryValueGenerationStrategy(
-					valueGeneration.getGenerationTiming(),
-					valueGeneration.getValueGenerator()
-			);
-		}
-
-		@Override
-		public GenerationTiming getGenerationTiming() {
-			return timing;
-		}
-
-		@Override
-		public ValueGenerator<?> getValueGenerator() {
-			return generator;
-		}
-	}
-
 	private static class NoInDatabaseValueGenerationStrategy implements InDatabaseValueGenerationStrategy {
 		/**
 		 * Singleton access

hibernate-core/src/test/java/org/hibernate/orm/test/mapping/generated/temporals/GeneratedUuidTests.java

@@ -19,10 +19,10 @@ import jakarta.persistence.Table;
 
 import org.hibernate.Session;
 import org.hibernate.annotations.ValueGenerationType;
+import org.hibernate.engine.spi.SharedSessionContractImplementor;
 import org.hibernate.tuple.AnnotationValueGenerationStrategy;
 import org.hibernate.tuple.GenerationTiming;
 import org.hibernate.tuple.InMemoryValueGenerationStrategy;
-import org.hibernate.tuple.ValueGenerator;
 
 import org.hibernate.testing.orm.junit.DomainModel;
 import org.hibernate.testing.orm.junit.SessionFactory;
@@ -66,9 +66,7 @@ public class GeneratedUuidTests {
 		assertThat( merged ).isNotNull();
 
 		// lastly, make sure we can load it..
-		final GeneratedUuidEntity loaded = scope.fromTransaction( (session) -> {
+		final GeneratedUuidEntity loaded = scope.fromTransaction( (session) -> session.get( GeneratedUuidEntity.class, 1 ));
-			return session.get( GeneratedUuidEntity.class, 1 );
-		} );
 
 		assertThat( loaded ).isNotNull();
 
@@ -88,7 +86,7 @@ public class GeneratedUuidTests {
 
 	//tag::mapping-generated-custom-ex3[]
 	public static class UuidValueGeneration
-			implements AnnotationValueGenerationStrategy<GeneratedUuidValue>, InMemoryValueGenerationStrategy, ValueGenerator<UUID> {
+			implements AnnotationValueGenerationStrategy<GeneratedUuidValue>, InMemoryValueGenerationStrategy {
 		private GenerationTiming timing;
 
 		@Override
@@ -102,12 +100,7 @@ public class GeneratedUuidTests {
 		}
 
 		@Override
-		public ValueGenerator<?> getValueGenerator() {
+		public Object generate(SharedSessionContractImplementor session, Object owner, Object currentValue) {
-			return this;
-		}
-
-		@Override
-		public UUID generateValue(Session session, Object owner) {
 			return UUID.randomUUID();
 		}
 	}