org.eclipse.gmf.runtime.diagram.ui/src/org/eclipse/gmf/runtime/diagram/ui/services/decorator/IDecorator.java

/******************************************************************************
 * Copyright (c) 2004, 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.gmf.runtime.diagram.ui.services.decorator;


/**
 * Clients providing an extension to the DecoratorService need to create  
 * a decorator class that implements the IDecorator interface.
 * 
 * This is the interface that a decorator must implement. A decorator is
 * installed on a decorator target to which it will add decoration figures.
 * 
 * @see IDecoratorProvider
 * 
 * @author cmahoney
 */
public interface IDecorator {
    /**
     * Activates this decorator. The decorator might need to hook listeners.
     * These listeners should be unhooked in <code>deactivate()</code>.
     * 
     * @see #deactivate()
     */
    public void activate();

    /**
     * Deactivates this decorator, the inverse of {@link #activate()}.
     * Deactivate is called when the host decorator target is deactivated.
     * Deactivate unhooks any listeners, and removes decoration figures that
     * have been added.
     * 
     * @see #activate()
     */
    public void deactivate();

    /**
     * Refreshes the decorations. This is called when the host decorator target
     * is refreshed.
     */
    public void refresh();
}