/*
 * $Id$
 *
 * License Agreement.
 *
 * Rich Faces - Natural Ajax for Java Server Faces (JSF)
 *
 * Copyright (C) 2007 Exadel, Inc.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License version 2.1 as published by the Free Software Foundation.
 *
 * This library 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 library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301  USA
 */
package org.richfaces.cdk.model;

import java.util.TreeMap;

/**
 * <p class="changed_added_4_0">
 * </p>
 *
 * @author asmirnov@exadel.com
 *
 */
public class ModelMap<K, E extends ModelElement<? super E>> extends TreeMap<K, E> {
    public static <I, T extends ModelElement<? super T>> ModelMap<I, T> create() {
        return new ModelMap<I, T>();
    }

    /**
     * <p class="changed_added_4_0">
     * </p>
     *
     * @param key
     * @param value
     * @return
     * @see java.util.Map#put(java.lang.Object, java.lang.Object)
     */
    public E put(K key, E value) {
        E oldValue = get(key);
        if (null != oldValue) {
            oldValue.merge(value);
        } else {
            super.put(key, value);
        }
        return oldValue;
    }
}
