| /******************************************************************************* |
| * Copyright (c) 2006, 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 |
| * Matthew Hall - bugs 251884, 194734 |
| *******************************************************************************/ |
| |
| package org.eclipse.core.databinding.observable.map; |
| |
| import java.util.Iterator; |
| import java.util.Map; |
| import java.util.Set; |
| |
| import org.eclipse.core.databinding.observable.IDiff; |
| |
| /** |
| * @since 1.1 |
| * |
| */ |
| public abstract class MapDiff implements IDiff { |
| /** |
| * Returns true if the diff has no added, removed or changed entries. |
| * |
| * @return true if the diff has no added, removed or changed entries. |
| * @since 1.2 |
| */ |
| public boolean isEmpty() { |
| return getAddedKeys().isEmpty() && getRemovedKeys().isEmpty() |
| && getChangedKeys().isEmpty(); |
| } |
| |
| /** |
| * Applies the changes in this diff to the given map |
| * |
| * @param map |
| * the map to which the diff will be applied |
| * @since 1.2 |
| */ |
| public void applyTo(Map map) { |
| for (Iterator it = getAddedKeys().iterator(); it.hasNext();) { |
| Object key = it.next(); |
| map.put(key, getNewValue(key)); |
| } |
| for (Iterator it = getChangedKeys().iterator(); it.hasNext();) { |
| Object key = it.next(); |
| map.put(key, getNewValue(key)); |
| } |
| for (Iterator it = getRemovedKeys().iterator(); it.hasNext();) { |
| map.remove(it.next()); |
| } |
| } |
| |
| /** |
| * @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); |
| } |