HHH-6084 define id strategy provider in HEM

hibernate-entitymanager/src/main/java/org/hibernate/ejb/AvailableSettings.java

@@ -256,6 +256,11 @@ public class AvailableSettings {
 	 */
 	public static final String SESSION_FACTORY_OBSERVER = "hibernate.ejb.session_factory_observer";
 
+	/**
+	 * IdentifierGeneratorStrategyRegisterer class name, the class must have a no-arg constructor
+	 */
+	public static final String IDENTIFIER_GENERATOR_STRATEGY_PROVIDER = "hibernate.ejb.identifier_generator_strategy_provider";
+
 	/**
 	 * Event configuration should follow the following pattern
 	 * hibernate.ejb.event.[eventType] f.q.c.n.EventListener1, f.q.c.n.EventListener12 ...

hibernate-entitymanager/src/main/java/org/hibernate/ejb/Ejb3Configuration.java

@@ -77,6 +77,7 @@
 import org.hibernate.cfg.Settings;
 import org.hibernate.cfg.SettingsFactory;
 import org.hibernate.cfg.annotations.reflection.XMLContext;
+import org.hibernate.ejb.cfg.spi.IdentifierGeneratorStrategyProvider;
 import org.hibernate.ejb.connection.InjectedDataSourceConnectionProvider;
 import org.hibernate.ejb.instrument.InterceptFieldClassFileTransformer;
 import org.hibernate.ejb.packaging.JarVisitorFactory;
@@ -91,6 +92,7 @@
 import org.hibernate.ejb.util.NamingHelper;
 import org.hibernate.engine.FilterDefinition;
 import org.hibernate.event.EventListeners;
+import org.hibernate.id.factory.DefaultIdentifierGeneratorFactory;
 import org.hibernate.mapping.AuxiliaryDatabaseObject;
 import org.hibernate.mapping.PersistentClass;
 import org.hibernate.persister.PersisterClassProvider;
@@ -1074,6 +1076,21 @@ else if ( propertyKey.startsWith( AvailableSettings.JACC_PREFIX )
 			cfg.setSessionFactoryObserver( observer );
 		}
 
+		final IdentifierGeneratorStrategyProvider strategyProvider = instantiateCustomClassFromConfiguration(
+				preparedProperties,
+				null,
+				null,
+				AvailableSettings.IDENTIFIER_GENERATOR_STRATEGY_PROVIDER,
+				"Identifier generator strategy provider",
+				IdentifierGeneratorStrategyProvider.class
+		);
+		if ( strategyProvider != null ) {
+			final DefaultIdentifierGeneratorFactory identifierGeneratorFactory = cfg.getIdentifierGeneratorFactory();
+			for ( Map.Entry<String,Class<?>> entry : strategyProvider.getStrategies().entrySet() ) {
+				identifierGeneratorFactory.register( entry.getKey(), entry.getValue() );
+			}
+		}
+
 		if ( jaccKeys.size() > 0 ) {
 			addSecurity( jaccKeys, preparedProperties, workingVars );
 		}

hibernate-entitymanager/src/main/java/org/hibernate/ejb/cfg/spi/IdentifierGeneratorStrategyProvider.java

@@ -0,0 +1,35 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * JBoss, Home of Professional Open Source
+ * Copyright 2011 Red Hat Inc. and/or its affiliates and other contributors
+ * as indicated by the @authors tag. All rights reserved.
+ * See the copyright.txt in the distribution for a
+ * full listing of individual contributors.
+ *
+ * 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, v. 2.1.
+ * This program is distributed in the hope that it will be useful, but WITHOUT A
+ * 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,
+ * v.2.1 along with this distribution; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+ * MA  02110-1301, USA.
+ */
+package org.hibernate.ejb.cfg.spi;
+
+import java.util.Map;
+
+/**
+ * Provide a set of IdentifierGenerator strategies allowing to override the Hibernate Core default ones
+ *
+ * @author Emmanuel Bernard <emmanuel@hibernate.org>
+ */
+public interface IdentifierGeneratorStrategyProvider {
+	/**
+	 * set of strategy / generator class pairs to register as accepted strategies
+	 */
+	Map<String,Class<?>> getStrategies();
+}