static final Integer N4 = 4;
  static final Integer N5 = 5;
  static final Integer NODE_NOT_IN_GRAPH = 1000;

  // TODO(user): Consider separating Strings that we've defined here to capture
  // identifiable substrings of expected error messages, from Strings that we've defined
  // here to provide error messages.
  // TODO(user): Some Strings used in the subclasses can be added as static Strings
  // here too.

  static final Integer N4 = 4;
  static final Integer N5 = 5;
  static final Integer NODE_NOT_IN_GRAPH = 1000;

  // TODO(user): Consider separating Strings that we've defined here to capture
  // identifiable substrings of expected error messages, from Strings that we've defined
  // here to provide error messages.
  // TODO(user): Some Strings used in the subclasses can be added as static Strings
  // here too.