@Override
  public ASTNode findChildByRole(int role) {
    LOG.assertTrue(ChildRole.isUnique(role));
    switch(role){
      case ChildRole.TYPE:
        return findChildByType(TYPE);

      case ChildRole.DOT:
        return findChildByType(DOT);

      case ChildRole.CLASS_KEYWORD:
        return findChildByType(CLASS_KEYWORD);

      default:
        return null;
    }
  }
@Override
  public ASTNode findChildByRole(int role)