/******************************************************************************* * Copyright (c) 2006 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 org.eclipse.ui.internal.services;import java.util.HashMap;import java.util.HashSet;import java.util.Map;import java.util.Set;import org.eclipse.ui.AbstractSourceProvider;import org.eclipse.ui.ISources;/** * <p> * A listener to changes in the showing menus. This is used to activate handlers * just for the span of a menu being shown. This is needed for full support for * legacy action-based extension points. * </p> * <p> * This class is only intended for internal use within * <code>org.eclipse.ui.workbench</code>. * </p> *  * @since 3.2 */public final class MenuSourceProvider extends AbstractSourceProvider {	/**	 * The names of the sources supported by this source provider.	 */	private static final String[] PROVIDED_SOURCE_NAMES = new String[] { ISources.ACTIVE_MENU_NAME };	/**	 * The menu ids that are currently showing, as known by this source	 * provider. This value may be <code>null</code>.	 */	private Set menuIds = new HashSet();	/**	 * Adds all of the given menu identifiers as being shown.	 * 	 * @param menuIds	 *            The ids of the menu that is now showing; must not be	 *            <code>null</code>.	 */	public final void addShowingMenus(final Set menuIds) {		this.menuIds.addAll(menuIds);		if (DEBUG) {			logDebuggingInfo("Menu ids changed to " + this.menuIds); //$NON-NLS-1$		}		fireSourceChanged(ISources.ACTIVE_MENU, ISources.ACTIVE_MENU_NAME,				this.menuIds);	}	public final void dispose() {		menuIds.clear();	}	public final Map getCurrentState() {		final Map state = new HashMap();		state.put(ISources.ACTIVE_MENU_NAME, menuIds);		return state;	}	public final String[] getProvidedSourceNames() {		return PROVIDED_SOURCE_NAMES;	}	/**	 * Removes all of the given menu identifiers as being shown.	 * 	 * @param menuIds	 *            The ids of the menu that is no longer shown; must not be	 *            <code>null</code>.	 */	public final void removeShowingMenus(final Set menuIds) {		this.menuIds.removeAll(menuIds);		if (DEBUG) {			logDebuggingInfo("Menu ids changed to " + this.menuIds); //$NON-NLS-1$		}		fireSourceChanged(ISources.ACTIVE_MENU, ISources.ACTIVE_MENU_NAME,				this.menuIds);	}}