mComputationTreeViewer.getControl().addKeyListener(new KeyListener() {
	@Override
	public void keyReleased(KeyEvent e) {}
	@Override
	public void keyPressed(KeyEvent e) {
		if((e.keyCode == 'c') && (e.stateMask == SWT.CTRL)) {
                       mCopyAction.run();
                }else if((e.keyCode == 'v') && (e.stateMask == SWT.CTRL)) {
                       mPasteAction.run();
                }else if((e.keyCode == 'z') && (e.stateMask == SWT.CTRL)) {
                       // Never call, WHY ????
                       mUndoAction.run();
                }else if((e.keyCode == 'y') && (e.stateMask == SWT.CTRL)) {
                       // Never call, WHY ????
                       mRedoAction.run();
                }
}});

// Handler activation
IHandlerService service = (IHandlerService) PlatformUI.getWorkbench().getService(IHandlerService.class);
AbstractHandler handler = new AbstractHandler() {
			@Override
			public Object execute(ExecutionEvent event) throws ExecutionException {
				mUndoAction.run();
				return null;
			}
};
IHandlerActivation handlerActivation = service.activateHandler("org.eclipse.ui.edit.undo", handler, new ActiveShellExpression(getShell()));





// Handler deactivation
service.deactivateHdanler(handlerActivation);
handlerActivation.getHandler().dispose();