/*
 * Hibernate, Relational Persistence for Idiomatic Java
 *
 * Copyright (c) 2014, 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.engine.spi;

Navigation methods for extra state objects attached to EntityEntry. 
Author:
Emmanuel Bernard /**
 * Navigation methods for extra state objects attached to {@link org.hibernate.engine.spi.EntityEntry}.
 *
 * @author Emmanuel Bernard <emmanuel@hibernate.org>
 */
public interface EntityEntryExtraState {

	
Attach additional state to the core state of EntityEntry 

Implementations must delegate to the next state or add it as next state if last in line.
/**
	 * Attach additional state to the core state of {@link org.hibernate.engine.spi.EntityEntry}
	 * <p>
	 * Implementations must delegate to the next state or add it as next state if last in line.
	 */
	void addExtraState(EntityEntryExtraState extraState);

	
Retrieve additional state by class type or null if no extra state of that type is present.

Implementations must return self if they match or delegate discovery to the next state in line.
/**
	 * Retrieve additional state by class type or null if no extra state of that type is present.
	 * <p>
	 * Implementations must return self if they match or delegate discovery to the next state in line.
	 */
	<T extends EntityEntryExtraState> T getExtraState(Class<T> extraStateType);

	//a remove method is ugly to define and has not real use case that we found: left out
}