/*
* JBoss, Home of Professional Open Source.
* Copyright 2008, Red Hat Middleware LLC, and individual contributors
* as indicated by the @author tags. See the copyright.txt file in the
* distribution for a full listing of individual contributors.
*
* This is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This software 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 software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.jboss.ejb.plugins.cmp.jdbc;
/**
* Implementations of this interface are used to create and compare field states
* for equality.
*
* @author <a href="mailto:alex@jboss.org">Alexey Loubyansky</a>
*/
public interface CMPFieldStateFactory
{
/**
* Calculates and returns an object that represents the state of the field value.
* The states produced by this method will be used to check whether the field
* is dirty at synchronization time.
*
* @param fieldValue field's value.
* @return an object representing the field's state.
*/
Object getFieldState(Object fieldValue);
/**
* Checks whether the field's state <code>state</code>
* is equal to the field value's state (possibly, calculated with
* the <code>getFieldState()</code> method).
*
* @param state the state to compare with field value's state.
* @param fieldValue field's value, the state of which will be compared
* with <code>state</code>.
* @return true if <code>state</code> equals to <code>fieldValue</code>'s state.
*/
boolean isStateValid(Object state, Object fieldValue);
}