Java tutorial
/******************************************************************************* * Copyright (c) 2000, 2015 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.jface.action; import org.eclipse.core.runtime.Assert; /** * Abstract superclass for group marker classes. * <p> * This class is not intended to be subclassed outside the framework. * </p> * @noextend This class is not intended to be subclassed by clients. */ public abstract class AbstractGroupMarker extends ContributionItem { /** * Constructor for use by subclasses. */ protected AbstractGroupMarker() { } /** * Create a new group marker with the given name. * The group name must not be <code>null</code> or the empty string. * The group name is also used as the item id. * * @param groupName the name of the group */ protected AbstractGroupMarker(String groupName) { super(groupName); Assert.isTrue(groupName != null && groupName.length() > 0); } /** * Returns the group name. * * @return the group name */ public String getGroupName() { return getId(); } /** * The <code>AbstractGroupMarker</code> implementation of this <code>IContributionItem</code> * method returns <code>true</code> iff the id is not <code>null</code>. Subclasses may override. */ @Override public boolean isGroupMarker() { return getId() != null; } }