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

      case ChildRole.RETURN_VALUE:
        return findChildByType(EXPRESSION_BIT_SET);

      case ChildRole.CLOSING_SEMICOLON:
        return TreeUtil.findChildBackward(this, SEMICOLON);

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