Class SpecialOperations


  • public final class SpecialOperations
    extends Object
    Special automata operations.
    • Method Detail

      • isFinite

        public static boolean isFinite​(Automaton a)
        Returns true if the language of this automaton is finite.
      • getCommonPrefix

        public static String getCommonPrefix​(Automaton a)
        Returns the longest string that is a prefix of all accepted strings and visits each state at most once.
        Returns:
        common prefix
      • getCommonPrefixBytesRef

        public static BytesRef getCommonPrefixBytesRef​(Automaton a)
      • getCommonSuffix

        public static String getCommonSuffix​(Automaton a)
        Returns the longest string that is a suffix of all accepted strings and visits each state at most once.
        Returns:
        common suffix
      • getCommonSuffixBytesRef

        public static BytesRef getCommonSuffixBytesRef​(Automaton a)
      • reverse

        public static Set<State> reverse​(Automaton a)
        Reverses the language of the given (non-singleton) automaton while returning the set of new initial states.
      • getFiniteStrings

        public static Set<IntsRef> getFiniteStrings​(Automaton a,
                                                    int limit)
        Returns the set of accepted strings, assuming that at most limit strings are accepted. If more than limit strings are accepted, the first limit strings found are returned. If limit<0, then the limit is infinite.