/*******************************************************************************
 * Copyright (c) 2006, 2007 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
 *******************************************************************************/

module org.eclipse.core.databinding.observable.map.MapDiff;

import java.lang.all;

import java.util.Set;

/**
 * @since 1.1
 * 
 */
public abstract class MapDiff {

    /**
     * @return the set of keys which were added
     */
    public abstract Set getAddedKeys();

    /**
     * @return the set of keys which were removed
     */
    public abstract Set getRemovedKeys();

    /**
     * @return the set of keys for which the value has changed
     */
    public abstract Set getChangedKeys();

    /**
     * Returns the old value for the given key, which must be an element of
     * {@link #getRemovedKeys()} or {@link #getChangedKeys()}.
     * 
     * @param key
     * @return the old value for the given key.
     */
    public abstract Object getOldValue(Object key);

    /**
     * Returns the new value for the given key, which must be an element of
     * {@link #getChangedKeys()} or {@link #getAddedKeys()}.
     * 
     * @param key
     * @return the new value for the given key.
     */
    public abstract Object getNewValue(Object key);
}