void configureKeyHandler() {
	KeyHandler keyHandler = new KeyHandler();
	IAction delete = actionRegistry.getAction(org.eclipse.ui.actions.ActionFactory.DELETE.getId());
	IAction zoomIn = actionRegistry.getAction(GEFActionConstants.ZOOM_IN);
	IAction zoomOut = actionRegistry.getAction(GEFActionConstants.ZOOM_OUT);
	keyHandler.put(KeyStroke.getPressed(SWT.DEL, 127, 0), delete);
	keyHandler.put(KeyStroke.getPressed('+', SWT.KEYPAD_ADD, 0), zoomIn);
	keyHandler.put(KeyStroke.getPressed('-', SWT.KEYPAD_SUBTRACT, 0), zoomOut);
	viewer.setKeyHandler(keyHandler);
}
 

@Override
protected void configureGraphicalViewer() {
	super.configureGraphicalViewer();

	MenuManager menu = SankeyMenu.create(this);
	getGraphicalViewer().setContextMenu(menu);

	GraphicalViewer viewer = getGraphicalViewer();
	viewer.setEditPartFactory(new SankeyEditPartFactory());
	ScalableRootEditPart root = new ScalableRootEditPart();
	viewer.setRootEditPart(root);

	// append zoom actions to action registry
	ZoomManager zoom = root.getZoomManager();
	getActionRegistry().registerAction(new ZoomInAction(zoom));
	getActionRegistry().registerAction(new ZoomOutAction(zoom));
	zoom.setZoomLevelContributions(Arrays.asList(
			ZoomManager.FIT_ALL,
			ZoomManager.FIT_HEIGHT,
			ZoomManager.FIT_WIDTH));

	// create key handler
	KeyHandler keyHandler = new KeyHandler();
	keyHandler.put(KeyStroke.getPressed('+', SWT.KEYPAD_ADD, 0),
			getActionRegistry().getAction(GEFActionConstants.ZOOM_IN));
	keyHandler.put(KeyStroke.getPressed('-', SWT.KEYPAD_SUBTRACT, 0),
			getActionRegistry().getAction(GEFActionConstants.ZOOM_OUT));
	viewer.setKeyHandler(keyHandler);

	viewer.setProperty(MouseWheelHandler.KeyGenerator.getKey(SWT.NONE),
			MouseWheelZoomHandler.SINGLETON);
}
 

public KeyHandler setParent( KeyHandler parent )
{
	return super.setParent( parent );
}
 

protected KeyHandler getKeyHandler() {
	return new KeyHandler();
}
 

/**
 * @return
 */
private KeyHandler getKeyHandler() {
    return new KeyHandler();
}