ISelectionService service = PlatformUI.getWorkbench().getActiveWorkbenchWindow().getSelectionService();
service.addSelectionListener(new ISelectionListener() {

@Override
public void selectionChanged(IWorkbenchPart part, ISelection selection) {
	if (selection instanceof IStructuredSelection) {
		IStructuredSelection sel = (IStructuredSelection) selection;
			if (!sel.isEmpty() 
                              && sel.getFirstElement() instanceof EditPart) {
				EditPart ep = (EditPart) sel.getFirstElement();
				if (ep.getModel() instanceof PictogramElement) {
					// do your thing
                                        System.out.println(ep.getModel());
				}
			}
		}

	}
});