HHH-9899 Enable integrators to plug in custom MetadataBuilder and Metadata

hibernate-core/src/main/java/org/hibernate/boot/MetadataBuilder.java

@@ -26,7 +26,6 @@ import org.hibernate.dialect.function.SQLFunction;
 import org.hibernate.type.BasicType;
 import org.hibernate.usertype.CompositeUserType;
 import org.hibernate.usertype.UserType;
-
 import org.jboss.jandex.IndexView;
 
 /**
@@ -395,6 +394,15 @@ public interface MetadataBuilder {
 //	 */
 //	public MetadataBuilder with(PersistentAttributeMemberResolver resolver);
 
+	/**
+	 * Allows unwrapping this builder as another, more specific type.
+	 *
+	 * @param type
+	 * @param <T>
+	 *
+	 * @return The unwrapped builder.
+	 */
+	public <T extends MetadataBuilder> T unwrap(Class<T> type);
 
 	/**
 	 * Actually build the metamodel

hibernate-core/src/main/java/org/hibernate/boot/MetadataSources.java

@@ -19,8 +19,10 @@ import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.jar.JarFile;
 import java.util.zip.ZipEntry;
+
 import javax.xml.transform.dom.DOMSource;
 
+import org.hibernate.HibernateException;
 import org.hibernate.boot.archive.spi.InputStreamAccess;
 import org.hibernate.boot.internal.MetadataBuilderImpl;
 import org.hibernate.boot.jaxb.Origin;
@@ -32,12 +34,14 @@ import org.hibernate.boot.jaxb.spi.Binding;
 import org.hibernate.boot.registry.BootstrapServiceRegistry;
 import org.hibernate.boot.registry.BootstrapServiceRegistryBuilder;
 import org.hibernate.boot.registry.StandardServiceRegistry;
+import org.hibernate.boot.registry.classloading.spi.ClassLoaderService;
+import org.hibernate.boot.spi.MetadataBuilderFactory;
 import org.hibernate.boot.spi.XmlMappingBinderAccess;
 import org.hibernate.internal.CoreLogging;
 import org.hibernate.internal.CoreMessageLogger;
+import org.hibernate.internal.util.StringHelper;
 import org.hibernate.service.ServiceRegistry;
 import org.hibernate.type.SerializationException;
-
 import org.w3c.dom.Document;
 
 /**
@@ -118,7 +122,8 @@ public class MetadataSources implements Serializable {
 	 * @return The built metadata.
 	 */
 	public MetadataBuilder getMetadataBuilder() {
-		return new MetadataBuilderImpl( this );
+		MetadataBuilderImpl defaultBuilder = new MetadataBuilderImpl( this );
+		return getCustomBuilderOrDefault( defaultBuilder );
 	}
 
 	/**
@@ -127,7 +132,40 @@ public class MetadataSources implements Serializable {
 	 * @return The built metadata.
 	 */
 	public MetadataBuilder getMetadataBuilder(StandardServiceRegistry serviceRegistry) {
-		return new MetadataBuilderImpl( this, serviceRegistry );
+		MetadataBuilderImpl defaultBuilder = new MetadataBuilderImpl( this, serviceRegistry );
+		return getCustomBuilderOrDefault( defaultBuilder );
+	}
+
+	/**
+	 * In case a custom {@link MetadataBuilderFactory} creates a custom builder, return that one, otherwise the default
+	 * builder.
+	 */
+	private MetadataBuilder getCustomBuilderOrDefault(MetadataBuilderImpl defaultBuilder) {
+		final ClassLoaderService cls = serviceRegistry.getService( ClassLoaderService.class );
+		final java.util.Collection<MetadataBuilderFactory> discoveredBuilderFactories = cls.loadJavaServices( MetadataBuilderFactory.class );
+
+		MetadataBuilder builder = null;
+		List<String> activeFactoryNames = null;
+
+		for ( MetadataBuilderFactory discoveredBuilderFactory : discoveredBuilderFactories ) {
+			final MetadataBuilder returnedBuilder = discoveredBuilderFactory.getMetadataBuilder( this, defaultBuilder );
+			if ( returnedBuilder != null ) {
+				if ( activeFactoryNames == null ) {
+					activeFactoryNames = new ArrayList<String>();
+				}
+				activeFactoryNames.add( discoveredBuilderFactory.getClass().getName() );
+				builder = returnedBuilder;
+			}
+		}
+
+		if ( activeFactoryNames != null && activeFactoryNames.size() > 1 ) {
+			throw new HibernateException(
+					"Multiple active MetadataBuilder definitions were discovered : " +
+							StringHelper.join( ", ", activeFactoryNames )
+			);
+		}
+
+		return builder != null ? builder : defaultBuilder;
 	}
 
 	/**

hibernate-core/src/main/java/org/hibernate/boot/internal/MetadataBuilderImpl.java

@@ -12,6 +12,7 @@ import java.util.Collections;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+
 import javax.persistence.AttributeConverter;
 import javax.persistence.SharedCacheMode;
 
@@ -74,7 +75,6 @@ import org.hibernate.type.CompositeCustomType;
 import org.hibernate.type.CustomType;
 import org.hibernate.usertype.CompositeUserType;
 import org.hibernate.usertype.UserType;
-
 import org.jboss.jandex.IndexView;
 
 import static org.hibernate.internal.log.DeprecationLogger.DEPRECATION_LOGGER;
@@ -385,6 +385,12 @@ public class MetadataBuilderImpl implements MetadataBuilderImplementor, TypeCont
 //		return this;
 //	}
 
+	@Override
+	@SuppressWarnings("unchecked")
+	public <T extends MetadataBuilder> T unwrap(Class<T> type) {
+		return (T) this;
+	}
+
 	@Override
 	public MetadataImplementor build() {
 		final CfgXmlAccessService cfgXmlAccessService = options.serviceRegistry.getService( CfgXmlAccessService.class );

hibernate-core/src/main/java/org/hibernate/boot/internal/SessionFactoryBuilderImpl.java

@@ -53,7 +53,6 @@ import org.hibernate.resource.transaction.TransactionCoordinatorBuilder;
 import org.hibernate.service.spi.ServiceRegistryImplementor;
 import org.hibernate.tuple.entity.EntityTuplizer;
 import org.hibernate.tuple.entity.EntityTuplizerFactory;
-
 import org.jboss.logging.Logger;
 
 import static org.hibernate.cfg.AvailableSettings.AUTO_CLOSE_SESSION;
@@ -78,6 +77,7 @@ import static org.hibernate.cfg.AvailableSettings.MAX_FETCH_DEPTH;
 import static org.hibernate.cfg.AvailableSettings.MULTI_TENANT_IDENTIFIER_RESOLVER;
 import static org.hibernate.cfg.AvailableSettings.ORDER_INSERTS;
 import static org.hibernate.cfg.AvailableSettings.ORDER_UPDATES;
+import static org.hibernate.cfg.AvailableSettings.PREFER_USER_TRANSACTION;
 import static org.hibernate.cfg.AvailableSettings.QUERY_CACHE_FACTORY;
 import static org.hibernate.cfg.AvailableSettings.QUERY_STARTUP_CHECKING;
 import static org.hibernate.cfg.AvailableSettings.QUERY_SUBSTITUTIONS;
@@ -98,7 +98,6 @@ import static org.hibernate.cfg.AvailableSettings.USE_SQL_COMMENTS;
 import static org.hibernate.cfg.AvailableSettings.USE_STRUCTURED_CACHE;
 import static org.hibernate.cfg.AvailableSettings.WRAP_RESULT_SETS;
 import static org.hibernate.engine.config.spi.StandardConverters.BOOLEAN;
-import static org.hibernate.cfg.AvailableSettings.PREFER_USER_TRANSACTION;
 
 /**
  * @author Gail Badner
@@ -110,7 +109,7 @@ public class SessionFactoryBuilderImpl implements SessionFactoryBuilderImplement
 	private final MetadataImplementor metadata;
 	private final SessionFactoryOptionsStateStandardImpl options;
 
-	SessionFactoryBuilderImpl(MetadataImplementor metadata) {
+	public SessionFactoryBuilderImpl(MetadataImplementor metadata) {
 		this.metadata = metadata;
 		this.options = new SessionFactoryOptionsStateStandardImpl( metadata.getMetadataBuildingOptions().getServiceRegistry() );
 

hibernate-core/src/main/java/org/hibernate/boot/spi/AbstractDelegatingMetadata.java

@@ -0,0 +1,225 @@
+/*
+ * Hibernate OGM, Domain model persistence for NoSQL datastores
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later
+ * See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
+ */
+package org.hibernate.boot.spi;
+
+import java.util.Collection;
+import java.util.Map;
+import java.util.Set;
+import java.util.UUID;
+
+import org.hibernate.MappingException;
+import org.hibernate.SessionFactory;
+import org.hibernate.boot.SessionFactoryBuilder;
+import org.hibernate.boot.model.IdentifierGeneratorDefinition;
+import org.hibernate.boot.model.TypeDefinition;
+import org.hibernate.boot.model.relational.Database;
+import org.hibernate.cfg.annotations.NamedEntityGraphDefinition;
+import org.hibernate.cfg.annotations.NamedProcedureCallDefinition;
+import org.hibernate.dialect.function.SQLFunction;
+import org.hibernate.engine.ResultSetMappingDefinition;
+import org.hibernate.engine.spi.FilterDefinition;
+import org.hibernate.engine.spi.NamedQueryDefinition;
+import org.hibernate.engine.spi.NamedSQLQueryDefinition;
+import org.hibernate.id.factory.IdentifierGeneratorFactory;
+import org.hibernate.internal.NamedQueryRepository;
+import org.hibernate.internal.SessionFactoryImpl;
+import org.hibernate.mapping.FetchProfile;
+import org.hibernate.mapping.MappedSuperclass;
+import org.hibernate.mapping.PersistentClass;
+import org.hibernate.mapping.Table;
+import org.hibernate.type.Type;
+import org.hibernate.type.TypeResolver;
+
+/**
+ * Convenience base class for custom implementors of {@link MetadataImplementor} using delegation.
+ *
+ * @author Gunnar Morling
+ *
+ */
+public abstract class AbstractDelegatingMetadata implements MetadataImplementor {
+
+	private final MetadataImplementor delegate;
+
+	public AbstractDelegatingMetadata(MetadataImplementor delegate) {
+		this.delegate = delegate;
+	}
+
+	@Override
+	public IdentifierGeneratorFactory getIdentifierGeneratorFactory() {
+		return delegate.getIdentifierGeneratorFactory();
+	}
+
+	@Override
+	public Type getIdentifierType(String className) throws MappingException {
+		return delegate.getIdentifierType( className );
+	}
+
+	@Override
+	public String getIdentifierPropertyName(String className) throws MappingException {
+		return delegate.getIdentifierPropertyName( className );
+	}
+
+	@Override
+	public Type getReferencedPropertyType(String className, String propertyName) throws MappingException {
+		return delegate.getReferencedPropertyType( className, propertyName );
+	}
+
+	@Override
+	public SessionFactoryBuilder getSessionFactoryBuilder() {
+		return delegate.getSessionFactoryBuilder();
+	}
+
+	@Override
+	public SessionFactory buildSessionFactory() {
+		return delegate.buildSessionFactory();
+	}
+
+	@Override
+	public UUID getUUID() {
+		return delegate.getUUID();
+	}
+
+	@Override
+	public Database getDatabase() {
+		return delegate.getDatabase();
+	}
+
+	@Override
+	public Collection<PersistentClass> getEntityBindings() {
+		return delegate.getEntityBindings();
+	}
+
+	@Override
+	public PersistentClass getEntityBinding(String entityName) {
+		return delegate.getEntityBinding( entityName );
+	}
+
+	@Override
+	public Collection<org.hibernate.mapping.Collection> getCollectionBindings() {
+		return delegate.getCollectionBindings();
+	}
+
+	@Override
+	public org.hibernate.mapping.Collection getCollectionBinding(String role) {
+		return delegate.getCollectionBinding( role );
+	}
+
+	@Override
+	public Map<String, String> getImports() {
+		return delegate.getImports();
+	}
+
+	@Override
+	public NamedQueryDefinition getNamedQueryDefinition(String name) {
+		return delegate.getNamedQueryDefinition( name );
+	}
+
+	@Override
+	public Collection<NamedQueryDefinition> getNamedQueryDefinitions() {
+		return delegate.getNamedQueryDefinitions();
+	}
+
+	@Override
+	public NamedSQLQueryDefinition getNamedNativeQueryDefinition(String name) {
+		return delegate.getNamedNativeQueryDefinition( name );
+	}
+
+	@Override
+	public Collection<NamedSQLQueryDefinition> getNamedNativeQueryDefinitions() {
+		return delegate.getNamedNativeQueryDefinitions();
+	}
+
+	@Override
+	public Collection<NamedProcedureCallDefinition> getNamedProcedureCallDefinitions() {
+		return delegate.getNamedProcedureCallDefinitions();
+	}
+
+	@Override
+	public ResultSetMappingDefinition getResultSetMapping(String name) {
+		return delegate.getResultSetMapping( name );
+	}
+
+	@Override
+	public Map<String, ResultSetMappingDefinition> getResultSetMappingDefinitions() {
+		return delegate.getResultSetMappingDefinitions();
+	}
+
+	@Override
+	public TypeDefinition getTypeDefinition(String typeName) {
+		return delegate.getTypeDefinition( typeName );
+	}
+
+	@Override
+	public Map<String, FilterDefinition> getFilterDefinitions() {
+		return delegate.getFilterDefinitions();
+	}
+
+	@Override
+	public FilterDefinition getFilterDefinition(String name) {
+		return delegate.getFilterDefinition( name );
+	}
+
+	@Override
+	public FetchProfile getFetchProfile(String name) {
+		return delegate.getFetchProfile( name );
+	}
+
+	@Override
+	public Collection<FetchProfile> getFetchProfiles() {
+		return delegate.getFetchProfiles();
+	}
+
+	@Override
+	public NamedEntityGraphDefinition getNamedEntityGraph(String name) {
+		return delegate.getNamedEntityGraph( name );
+	}
+
+	@Override
+	public Map<String, NamedEntityGraphDefinition> getNamedEntityGraphs() {
+		return delegate.getNamedEntityGraphs();
+	}
+
+	@Override
+	public IdentifierGeneratorDefinition getIdentifierGenerator(String name) {
+		return delegate.getIdentifierGenerator( name );
+	}
+
+	@Override
+	public Collection<Table> collectTableMappings() {
+		return delegate.collectTableMappings();
+	}
+
+	@Override
+	public Map<String, SQLFunction> getSqlFunctionMap() {
+		return delegate.getSqlFunctionMap();
+	}
+
+	@Override
+	public MetadataBuildingOptions getMetadataBuildingOptions() {
+		return delegate.getMetadataBuildingOptions();
+	}
+
+	@Override
+	public TypeResolver getTypeResolver() {
+		return delegate.getTypeResolver();
+	}
+
+	@Override
+	public NamedQueryRepository buildNamedQueryRepository(SessionFactoryImpl sessionFactory) {
+		return delegate.buildNamedQueryRepository( sessionFactory );
+	}
+
+	@Override
+	public void validate() throws MappingException {
+		delegate.validate();
+	}
+
+	@Override
+	public Set<MappedSuperclass> getMappedSuperclassMappingsCopy() {
+		return delegate.getMappedSuperclassMappingsCopy();
+	}
+}

hibernate-core/src/main/java/org/hibernate/boot/spi/AbstractDelegatingMetadataBuilderImplementor.java

@@ -0,0 +1,251 @@
+/*
+ * Hibernate OGM, Domain model persistence for NoSQL datastores
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later
+ * See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
+ */
+package org.hibernate.boot.spi;
+
+import javax.persistence.AttributeConverter;
+import javax.persistence.SharedCacheMode;
+
+import org.hibernate.annotations.common.reflection.ReflectionManager;
+import org.hibernate.boot.CacheRegionDefinition;
+import org.hibernate.boot.MetadataBuilder;
+import org.hibernate.boot.archive.scan.spi.ScanEnvironment;
+import org.hibernate.boot.archive.scan.spi.ScanOptions;
+import org.hibernate.boot.archive.scan.spi.Scanner;
+import org.hibernate.boot.archive.spi.ArchiveDescriptorFactory;
+import org.hibernate.boot.model.IdGeneratorStrategyInterpreter;
+import org.hibernate.boot.model.TypeContributor;
+import org.hibernate.boot.model.naming.ImplicitNamingStrategy;
+import org.hibernate.boot.model.naming.PhysicalNamingStrategy;
+import org.hibernate.boot.model.relational.AuxiliaryDatabaseObject;
+import org.hibernate.cache.spi.access.AccessType;
+import org.hibernate.cfg.AttributeConverterDefinition;
+import org.hibernate.cfg.MetadataSourceType;
+import org.hibernate.dialect.function.SQLFunction;
+import org.hibernate.type.BasicType;
+import org.hibernate.usertype.CompositeUserType;
+import org.hibernate.usertype.UserType;
+import org.jboss.jandex.IndexView;
+
+/**
+ * Convenience base class for custom implementors of {@link MetadataBuilderImplementor} using delegation.
+ *
+ * @author Gunnar Morling
+ *
+ * @param <T> The type of a specific sub-class; Allows sub-classes to narrow down the return-type of the contract methods
+ * to a specialization of {@link MetadataBuilderImplementor}
+ */
+public abstract class AbstractDelegatingMetadataBuilderImplementor<T extends AbstractDelegatingMetadataBuilderImplementor<T>>  implements MetadataBuilderImplementor {
+
+	private final MetadataBuilderImplementor delegate;
+
+	public MetadataBuilderImplementor getDelegate() {
+		return delegate;
+	}
+
+	public AbstractDelegatingMetadataBuilderImplementor(MetadataBuilderImplementor delegate) {
+		this.delegate = delegate;
+	}
+
+	/**
+	 * Returns a specific implementation. See the <a
+	 * href="http://www.angelikalanger.com/GenericsFAQ/FAQSections/ProgrammingIdioms.html#FAQ206">What is the
+	 * "getThis trick?"</a>.
+	 */
+	protected abstract T getThis();
+
+	@Override
+	public MetadataBuilder applyImplicitSchemaName(String implicitSchemaName) {
+		delegate.applyImplicitSchemaName( implicitSchemaName );
+		return getThis();
+	}
+
+	@Override
+	public MetadataBuilder applyImplicitCatalogName(String implicitCatalogName) {
+		delegate.applyImplicitCatalogName( implicitCatalogName );
+		return getThis();
+	}
+
+	@Override
+	public MetadataBuilder applyImplicitNamingStrategy(ImplicitNamingStrategy namingStrategy) {
+		delegate.applyImplicitNamingStrategy( namingStrategy );
+		return getThis();
+	}
+
+	@Override
+	public MetadataBuilder applyPhysicalNamingStrategy(PhysicalNamingStrategy namingStrategy) {
+		delegate.applyPhysicalNamingStrategy( namingStrategy );
+		return getThis();
+	}
+
+	@Override
+	public MetadataBuilder applyReflectionManager(ReflectionManager reflectionManager) {
+		delegate.applyReflectionManager( reflectionManager );
+		return getThis();
+	}
+
+	@Override
+	public MetadataBuilder applySharedCacheMode(SharedCacheMode cacheMode) {
+		delegate.applySharedCacheMode( cacheMode );
+		return getThis();
+	}
+
+	@Override
+	public MetadataBuilder applyAccessType(AccessType accessType) {
+		delegate.applyAccessType( accessType );
+		return getThis();
+	}
+
+	@Override
+	public MetadataBuilder applyIndexView(IndexView jandexView) {
+		delegate.applyIndexView( jandexView );
+		return getThis();
+	}
+
+	@Override
+	public MetadataBuilder applyScanOptions(ScanOptions scanOptions) {
+		delegate.applyScanOptions( scanOptions );
+		return getThis();
+	}
+
+	@Override
+	public MetadataBuilder applyScanEnvironment(ScanEnvironment scanEnvironment) {
+		delegate.applyScanEnvironment( scanEnvironment );
+		return getThis();
+	}
+
+	@Override
+	public MetadataBuilder applyScanner(Scanner scanner) {
+		delegate.applyScanner( scanner );
+		return getThis();
+	}
+
+	@Override
+	public MetadataBuilder applyArchiveDescriptorFactory(ArchiveDescriptorFactory factory) {
+		delegate.applyArchiveDescriptorFactory( factory );
+		return getThis();
+	}
+
+	@Override
+	public MetadataBuilder enableNewIdentifierGeneratorSupport(boolean enable) {
+		delegate.enableNewIdentifierGeneratorSupport( enable );
+		return getThis();
+	}
+
+	@Override
+	public MetadataBuilder enableExplicitDiscriminatorsForJoinedSubclassSupport(boolean enabled) {
+		delegate.enableExplicitDiscriminatorsForJoinedSubclassSupport( enabled );
+		return getThis();
+	}
+
+	@Override
+	public MetadataBuilder enableImplicitDiscriminatorsForJoinedSubclassSupport(boolean enabled) {
+		delegate.enableImplicitDiscriminatorsForJoinedSubclassSupport( enabled );
+		return getThis();
+	}
+
+	@Override
+	public MetadataBuilder enableImplicitForcingOfDiscriminatorsInSelect(boolean supported) {
+		delegate.enableImplicitForcingOfDiscriminatorsInSelect( supported );
+		return getThis();
+	}
+
+	@Override
+	public MetadataBuilder enableGlobalNationalizedCharacterDataSupport(boolean enabled) {
+		delegate.enableGlobalNationalizedCharacterDataSupport( enabled );
+		return getThis();
+	}
+
+	@Override
+	public MetadataBuilder applyBasicType(BasicType type) {
+		delegate.applyBasicType( type );
+		return getThis();
+	}
+
+	@Override
+	public MetadataBuilder applyBasicType(UserType type, String[] keys) {
+		delegate.applyBasicType( type, keys );
+		return getThis();
+	}
+
+	@Override
+	public MetadataBuilder applyBasicType(CompositeUserType type, String[] keys) {
+		delegate.applyBasicType( type, keys );
+		return getThis();
+	}
+
+	@Override
+	public MetadataBuilder applyTypes(TypeContributor typeContributor) {
+		delegate.applyTypes( typeContributor );
+		return getThis();
+	}
+
+	@Override
+	public MetadataBuilder applyCacheRegionDefinition(CacheRegionDefinition cacheRegionDefinition) {
+		delegate.applyCacheRegionDefinition( cacheRegionDefinition );
+		return getThis();
+	}
+
+	@Override
+	public MetadataBuilder applyTempClassLoader(ClassLoader tempClassLoader) {
+		delegate.applyTempClassLoader( tempClassLoader );
+		return getThis();
+	}
+
+	@Override
+	public MetadataBuilder applySourceProcessOrdering(MetadataSourceType... sourceTypes) {
+		delegate.applySourceProcessOrdering( sourceTypes );
+		return getThis();
+	}
+
+	@Override
+	public MetadataBuilder applySqlFunction(String functionName, SQLFunction function) {
+		delegate.applySqlFunction( functionName, function );
+		return getThis();
+	}
+
+	@Override
+	public MetadataBuilder applyAuxiliaryDatabaseObject(AuxiliaryDatabaseObject auxiliaryDatabaseObject) {
+		delegate.applyAuxiliaryDatabaseObject( auxiliaryDatabaseObject );
+		return getThis();
+	}
+
+	@Override
+	public MetadataBuilder applyAttributeConverter(AttributeConverterDefinition definition) {
+		delegate.applyAttributeConverter( definition );
+		return getThis();
+	}
+
+	@Override
+	public MetadataBuilder applyAttributeConverter(Class<? extends AttributeConverter> attributeConverterClass) {
+		delegate.applyAttributeConverter( attributeConverterClass );
+		return getThis();
+	}
+
+	@Override
+	public MetadataBuilder applyAttributeConverter(Class<? extends AttributeConverter> attributeConverterClass, boolean autoApply) {
+		delegate.applyAttributeConverter( attributeConverterClass, autoApply );
+		return getThis();
+	}
+
+	@Override
+	public MetadataBuilder applyAttributeConverter(AttributeConverter attributeConverter) {
+		delegate.applyAttributeConverter( attributeConverter );
+		return getThis();
+	}
+
+	@Override
+	public MetadataBuilder applyAttributeConverter(AttributeConverter attributeConverter, boolean autoApply) {
+		delegate.applyAttributeConverter( attributeConverter, autoApply );
+		return getThis();
+	}
+
+	@Override
+	public MetadataBuilder applyIdGenerationTypeInterpreter(IdGeneratorStrategyInterpreter interpreter) {
+		delegate.applyIdGenerationTypeInterpreter( interpreter );
+		return getThis();
+	}
+}

hibernate-core/src/main/java/org/hibernate/boot/spi/AbstractDelegatingMetadataBuildingOptions.java

@@ -0,0 +1,174 @@
+/*
+ * Hibernate OGM, Domain model persistence for NoSQL datastores
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later
+ * See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
+ */
+package org.hibernate.boot.spi;
+
+import java.util.List;
+import java.util.Map;
+
+import javax.persistence.SharedCacheMode;
+
+import org.hibernate.MultiTenancyStrategy;
+import org.hibernate.annotations.common.reflection.ReflectionManager;
+import org.hibernate.boot.CacheRegionDefinition;
+import org.hibernate.boot.archive.scan.spi.ScanEnvironment;
+import org.hibernate.boot.archive.scan.spi.ScanOptions;
+import org.hibernate.boot.archive.spi.ArchiveDescriptorFactory;
+import org.hibernate.boot.model.IdGeneratorStrategyInterpreter;
+import org.hibernate.boot.model.naming.ImplicitNamingStrategy;
+import org.hibernate.boot.model.naming.PhysicalNamingStrategy;
+import org.hibernate.boot.model.relational.AuxiliaryDatabaseObject;
+import org.hibernate.boot.registry.StandardServiceRegistry;
+import org.hibernate.cache.spi.access.AccessType;
+import org.hibernate.cfg.AttributeConverterDefinition;
+import org.hibernate.cfg.MetadataSourceType;
+import org.hibernate.dialect.function.SQLFunction;
+import org.hibernate.type.BasicType;
+import org.jboss.jandex.IndexView;
+
+/**
+ * Convenience base class for custom implementors of {@link MetadataBuildingOptions} using delegation.
+ *
+ * @author Gunnar Morling
+ */
+public abstract class AbstractDelegatingMetadataBuildingOptions implements MetadataBuildingOptions {
+
+	private final MetadataBuildingOptions delegate;
+
+	public AbstractDelegatingMetadataBuildingOptions(MetadataBuildingOptions delegate) {
+		this.delegate = delegate;
+	}
+
+	@Override
+	public StandardServiceRegistry getServiceRegistry() {
+		return delegate.getServiceRegistry();
+	}
+
+	@Override
+	public MappingDefaults getMappingDefaults() {
+		return delegate.getMappingDefaults();
+	}
+
+	@Override
+	public List<BasicType> getBasicTypeRegistrations() {
+		return delegate.getBasicTypeRegistrations();
+	}
+
+	@Override
+	public IndexView getJandexView() {
+		return delegate.getJandexView();
+	}
+
+	@Override
+	public ScanOptions getScanOptions() {
+		return delegate.getScanOptions();
+	}
+
+	@Override
+	public ScanEnvironment getScanEnvironment() {
+		return delegate.getScanEnvironment();
+	}
+
+	@Override
+	public Object getScanner() {
+		return delegate.getScanner();
+	}
+
+	@Override
+	public ArchiveDescriptorFactory getArchiveDescriptorFactory() {
+		return delegate.getArchiveDescriptorFactory();
+	}
+
+	@Override
+	public ClassLoader getTempClassLoader() {
+		return delegate.getTempClassLoader();
+	}
+
+	@Override
+	public ImplicitNamingStrategy getImplicitNamingStrategy() {
+		return delegate.getImplicitNamingStrategy();
+	}
+
+	@Override
+	public PhysicalNamingStrategy getPhysicalNamingStrategy() {
+		return delegate.getPhysicalNamingStrategy();
+	}
+
+	@Override
+	public ReflectionManager getReflectionManager() {
+		return delegate.getReflectionManager();
+	}
+
+	@Override
+	public SharedCacheMode getSharedCacheMode() {
+		return delegate.getSharedCacheMode();
+	}
+
+	@Override
+	public AccessType getImplicitCacheAccessType() {
+		return delegate.getImplicitCacheAccessType();
+	}
+
+	@Override
+	public MultiTenancyStrategy getMultiTenancyStrategy() {
+		return delegate.getMultiTenancyStrategy();
+	}
+
+	@Override
+	public IdGeneratorStrategyInterpreter getIdGenerationTypeInterpreter() {
+		return delegate.getIdGenerationTypeInterpreter();
+	}
+
+	@Override
+	public List<CacheRegionDefinition> getCacheRegionDefinitions() {
+		return delegate.getCacheRegionDefinitions();
+	}
+
+	@Override
+	public boolean ignoreExplicitDiscriminatorsForJoinedInheritance() {
+		return delegate.ignoreExplicitDiscriminatorsForJoinedInheritance();
+	}
+
+	@Override
+	public boolean createImplicitDiscriminatorsForJoinedInheritance() {
+		return delegate.createImplicitDiscriminatorsForJoinedInheritance();
+	}
+
+	@Override
+	public boolean shouldImplicitlyForceDiscriminatorInSelect() {
+		return delegate.shouldImplicitlyForceDiscriminatorInSelect();
+	}
+
+	@Override
+	public boolean useNationalizedCharacterData() {
+		return delegate.useNationalizedCharacterData();
+	}
+
+	@Override
+	public boolean isSpecjProprietarySyntaxEnabled() {
+		return delegate.isSpecjProprietarySyntaxEnabled();
+	}
+
+	@Override
+	public List<MetadataSourceType> getSourceProcessOrdering() {
+		return delegate.getSourceProcessOrdering();
+	}
+
+	@Override
+	public Map<String, SQLFunction> getSqlFunctions() {
+		return delegate.getSqlFunctions();
+	}
+
+	@Override
+	public List<AuxiliaryDatabaseObject> getAuxiliaryDatabaseObjectList() {
+		return delegate.getAuxiliaryDatabaseObjectList();
+	}
+
+	@Override
+	public List<AttributeConverterDefinition> getAttributeConverters() {
+		return delegate.getAttributeConverters();
+	}
+}

hibernate-core/src/main/java/org/hibernate/boot/spi/MetadataBuilderFactory.java

@@ -0,0 +1,29 @@
+/*
+ * Hibernate OGM, Domain model persistence for NoSQL datastores
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later
+ * See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
+ */
+package org.hibernate.boot.spi;
+
+import org.hibernate.boot.Metadata;
+import org.hibernate.boot.MetadataSources;
+
+/**
+ * An extension point for integrators that wish to hook into the process of how a {@link Metadata} is built. Intended as
+ * a "discoverable service" ({@link java.util.ServiceLoader}). There can be at most one implementation discovered that
+ * returns a non-null SessionFactoryBuilder.
+ *
+ * @author Gunnar Morling
+ */
+public interface MetadataBuilderFactory {
+
+	/**
+	 * Creates a {@link MetadataBuilderImplementor}.
+	 *
+	 * @param metadatasources The current metadata sources
+	 * @param defaultBuilder The default builder, may be used as a delegate
+	 * @return a new metadata builder
+	 */
+	MetadataBuilderImplementor getMetadataBuilder(MetadataSources metadatasources, MetadataBuilderImplementor defaultBuilder);
+}