@Override
  protected void installOperations() {
    myOperations.add(createAcceptOperation(ThreeSide.LEFT, ThreeSide.BASE));
    myOperations.add(createAcceptOperation(ThreeSide.RIGHT, ThreeSide.BASE));
    myOperations.add(createAcceptOperation(ThreeSide.BASE, ThreeSide.LEFT));
    myOperations.add(createAcceptOperation(ThreeSide.BASE, ThreeSide.RIGHT));
  }
@Override
  protected void installOperations()