/*******************************************************************************
 * Copyright (c) 2000, 2009 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package com.liferay.ide.core.model;

/**
 * Classes that implement this interface are capable of notifying listeners
 * about model changes. Interested parties should implement
 * <samp>IModelChangedListener </samp> and add as listeners to be able to
 * receive change notification.
 * 
 * @noimplement This interface is not intended to be implemented by clients.
 * @noextend This interface is not intended to be extended by clients.
 * @since 2.0
 */
public interface IModelChangeProvider {
	/**
	 * Adds the listener to the list of listeners that will be notified on model
	 * changes.
	 * 
	 * @param listener
	 *            a model change listener to be added
	 */
	public void addModelChangedListener(IModelChangedListener listener);

	/**
	 * Delivers change event to all the registered listeners.
	 * 
	 * @param event
	 *            a change event that will be passed to all the listeners
	 */
	public void fireModelChanged(IModelChangedEvent event);

	/**
	 * Notifies listeners that a property of a model object changed. This is a
	 * utility method that will create a model event and fire it.
	 * 
	 * @param object
	 *            an affected model object
	 * @param property
	 *            name of the property that has changed
	 * @param oldValue
	 *            the old value of the property
	 * @param newValue
	 *            the new value of the property
	 */
	public void fireModelObjectChanged(Object object, String property, Object oldValue, Object newValue);

	/**
	 * Takes the listener off the list of registered change listeners.
	 * 
	 * @param listener
	 *            a model change listener to be removed
	 */
	public void removeModelChangedListener(IModelChangedListener listener);
}