Interface AlphabetIndex

  • All Superinterfaces:

    public interface AlphabetIndex
    extends Changeable

    Map between Symbols and index numbers.

    The Symbols will all come from a single finite alphabet. The indices will range from 0 to getAlphabet().size()-1 inclusive with each symbol having a unique index. The resulting table can be used to look up array indices by symbol, which in many cases will be more efficient than performing a Map operation on, for example, a HashMap.

    An index should do whatever is necessary to stay synchronized with its alphabet. It may chose to modify the index table with the alphabet, or to veto all changes to the alphabet that would invalidate the indexing scheme.

    Thomas Down, Matthew pocock
    • Field Detail

      • INDEX

        static final ChangeType INDEX

        Indicates that the index is changing, probably due to the underlying alphabet changing.

        The previous & changed fields should be arrays of symbols in the order they are indexed in the unmodified and modified indices respectively.