bundles/org.eclipse.ui.workbench/Eclipse UI/org/eclipse/ui/internal/registry/ICategory.java

/*******************************************************************************
 * Copyright (c) 2000, 2003 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials 
 * are made available under the terms of the Common Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/cpl-v10.html
 * 
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.ui.internal.registry;

import java.util.ArrayList;

import org.eclipse.core.runtime.IAdaptable;
import org.eclipse.ui.internal.WorkbenchMessages;
import org.eclipse.ui.model.IWorkbenchAdapter;

/**
 * Category provides for hierarchical grouping of elements
 * registered in the registry. One extension normally defines
 * a category, and other reference it via its ID.
 * <p>
 * A category may specify its parent category in order to
 * achieve hierarchy.
 * </p><p>
 * [Issue: This interface is not exposed in API, but time may
 * demonstrate that it should be.  For the short term leave it be.
 * In the long term its use should be re-evaluated.]
 * </p>
 */
public interface ICategory extends IWorkbenchAdapter, IAdaptable {
	/**
	 * Name of the miscellaneous category
	 */
	public final static String MISC_NAME = WorkbenchMessages.getString("ICategory.other"); //$NON-NLS-1$
	
	/**
	 * Identifier of the miscellaneous category
	 */
	public final static String MISC_ID = "org.eclipse.ui.internal.otherCategory"; //$NON-NLS-1$
	
	/**
	 * Adds an element as being part of this category
	 */
	public void addElement(Object element);

	/**
	 * Returns the element that are known to be part
	 * of this category or <code>null</code>.
	 */
	public ArrayList getElements();
	
	/**
	 * Returns a unique category ID.
	 */
	public String getId();
	
	/**
	 * Returns a presentation label for this category.
	 */
	public String getLabel();
	
	/**
	 * Returns an array of category IDs that represent a path
	 * to the parent category of this category. If this is a
	 * top-level category, <code>null</code> is returned.
	 */
	public String[] getParentPath();
	
	/**
	 * Returns the category ID that represents the root
	 * of the parent category of this category. If this is a
	 * top-level category, <code>null</code> is returned.
	 */
	public String getRootPath();
	
	/**
	 * Returns whether the category contains any elements.
	 */
	public boolean hasElements();
}