public OperatorNode(String value) {

    super(value);

    if (value.equalsIgnoreCase("AND") || value.equalsIgnoreCase("OR")) {
      numOfChildren = 2;
    } else if (value.equalsIgnoreCase("NOT")) {
      numOfChildren = 1;
    } else {
      System.out.println("Error # 1");
    }
  }