StsToolEditPartProvider.java

/*
* StsToolEditPartProvider.java
*
* This file is part of the STS-Tool project.
* Copyright (c) 2011-2012 "University of Trento - DISI" All rights reserved.
*
* Is strictly forbidden to remove this copyright notice from this source code.
*
* Disclaimer of Warranty:
* STS-Tool (this software) is provided "as-is" and without warranty of any kind, 
* express, implied or otherwise, including without limitation, any warranty of 
* merchantability or fitness for a particular purpose.
* In no event shall the copyright holder or contributors be liable for any direct,
* indirect, incidental, special, exemplary, or consequential damages
* including, but not limited to, procurement of substitute goods or services;
* loss of use, data, or profits; or business interruption) however caused and on
* any theory of liability, whether in contract, strict liability, or tort (including
* negligence or otherwise) arising in any way out of the use of this software, even 
* if advised of the possibility of such damage.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License version 3
* as published by the Free Software Foundation with the addition of the
* following permission added to Section 15 as permitted in Section 7(a):
* FOR ANY PART OF THE COVERED WORK IN WHICH THE COPYRIGHT IS OWNED BY 
* "University of Trento - DISI","University of Trento - DISI" DISCLAIMS THE
* WARRANTY OF NON INFRINGEMENT OF THIRD PARTY RIGHTS.
*
* See the GNU Affero General Public License for more details.
* You should have received a copy of the GNU Affero General Public License
* along with this program; if not, see http://www.gnu.org/licenses or write to
* the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA, 02110-1301 USA, or download the license from the following URL:
* http://www.sts-tool.eu/License.php
*
* For more information, please contact STS-Tool group at this
* address: ststool@disi.unitn.it
*
*/
package eu.aniketos.wp1.ststool.diagram.providers;

import java.lang.ref.WeakReference;
import org.eclipse.gef.EditPart;
import org.eclipse.gef.EditPartFactory;
import org.eclipse.gmf.runtime.common.core.service.IOperation;
import org.eclipse.gmf.runtime.diagram.ui.editparts.IGraphicalEditPart;
import org.eclipse.gmf.runtime.diagram.ui.services.editpart.AbstractEditPartProvider;
import org.eclipse.gmf.runtime.diagram.ui.services.editpart.CreateGraphicEditPartOperation;
import org.eclipse.gmf.runtime.diagram.ui.services.editpart.IEditPartOperation;
import org.eclipse.gmf.runtime.notation.View;
import eu.aniketos.wp1.ststool.diagram.edit.parts.StsToolDiagramEditPart;
import eu.aniketos.wp1.ststool.diagram.edit.parts.StsToolEditPartFactory;
import eu.aniketos.wp1.ststool.diagram.part.StsToolVisualIDRegistry;

/**
 * @generated
 */
public class StsToolEditPartProvider extends AbstractEditPartProvider {

	/**
	 * @generated
	 */
	private EditPartFactory	factory;

	/**
	 * @generated
	 */
	private boolean			allowCaching;

	/**
	 * @generated
	 */
	private WeakReference	cachedPart;

	/**
	 * @generated
	 */
	private WeakReference	cachedView;

	/**
	 * @generated
	 */
	public StsToolEditPartProvider() {
		setFactory(new StsToolEditPartFactory());
		setAllowCaching(true);
	}

	/**
	 * @generated
	 */
	public final EditPartFactory getFactory(){
		return factory;
	}

	/**
	 * @generated
	 */
	protected void setFactory(EditPartFactory factory){
		this.factory = factory;
	}

	/**
	 * @generated
	 */
	public final boolean isAllowCaching(){
		return allowCaching;
	}

	/**
	 * @generated
	 */
	protected synchronized void setAllowCaching(boolean allowCaching){
		this.allowCaching = allowCaching;
		if (!allowCaching) {
			cachedPart = null;
			cachedView = null;
		}
	}

	/**
	 * @generated
	 */
	protected IGraphicalEditPart createEditPart(View view){
		EditPart part = factory.createEditPart(null, view);
		if (part instanceof IGraphicalEditPart) { return (IGraphicalEditPart) part; }
		return null;
	}

	/**
	 * @generated
	 */
	protected IGraphicalEditPart getCachedPart(View view){
		if (cachedView != null && cachedView.get() == view) { return (IGraphicalEditPart) cachedPart.get(); }
		return null;
	}

	/**
	 * @generated
	 */
	@Override
	public synchronized IGraphicalEditPart createGraphicEditPart(View view){
		if (isAllowCaching()) {
			IGraphicalEditPart part = getCachedPart(view);
			cachedPart = null;
			cachedView = null;
			if (part != null) { return part; }
		}
		return createEditPart(view);
	}

	/**
	 * @generated
	 */
	@Override
	public synchronized boolean provides(IOperation operation){
		if (operation instanceof CreateGraphicEditPartOperation) {
			View view = ((IEditPartOperation) operation).getView();
			if (!StsToolDiagramEditPart.MODEL_ID.equals(StsToolVisualIDRegistry.getModelID(view))) { return false; }
			if (isAllowCaching() && getCachedPart(view) != null) { return true; }
			IGraphicalEditPart part = createEditPart(view);
			if (part != null) {
				if (isAllowCaching()) {
					cachedPart = new WeakReference(part);
					cachedView = new WeakReference(view);
				}
				return true;
			}
		}
		return false;
	}
}