public IntPair insertNFA()

in jflex/src/main/java/jflex/core/NFA.java [829:927]
66 lines of code
12 McCabe index (conditional complexity)

  public IntPair insertNFA(RegExp regExp) {

    IntPair nfa1, nfa2;
    int start, end;
    RegExp2 r;

    if (Build.DEBUG) {
      Out.debug("Inserting RegExp : " + regExp);
    }

    if (regExp.isCharClass()) {
      start = numStates;
      end = numStates + 1;

      ensureCapacity(end + 1);
      numStates = end + 1;

      insertCCLNFA(regExp, start, end);

      return IntPair.create(start, end);
    }

    switch (regExp.type) {
      case sym.BAR:
        r = (RegExp2) regExp;

        nfa1 = insertNFA(r.r1);
        nfa2 = insertNFA(r.r2);

        start = nfa2.end() + 1;
        end = nfa2.end() + 2;

        addEpsilonTransition(start, nfa1.start());
        addEpsilonTransition(start, nfa2.start());
        addEpsilonTransition(nfa1.end(), end);
        addEpsilonTransition(nfa2.end(), end);

        return IntPair.create(start, end);

      case sym.CONCAT:
        r = (RegExp2) regExp;

        nfa1 = insertNFA(r.r1);
        nfa2 = insertNFA(r.r2);

        addEpsilonTransition(nfa1.end(), nfa2.start());

        return IntPair.create(nfa1.start(), nfa2.end());

      case sym.STAR:
        nfa1 = insertNFA((RegExp) ((RegExp1) regExp).content);

        start = nfa1.end() + 1;
        end = nfa1.end() + 2;

        addEpsilonTransition(nfa1.end(), end);
        addEpsilonTransition(start, nfa1.start());

        addEpsilonTransition(start, end);
        addEpsilonTransition(nfa1.end(), nfa1.start());

        return IntPair.create(start, end);

      case sym.PLUS:
        nfa1 = insertNFA((RegExp) ((RegExp1) regExp).content);

        start = nfa1.end() + 1;
        end = nfa1.end() + 2;

        addEpsilonTransition(nfa1.end(), end);
        addEpsilonTransition(start, nfa1.start());

        addEpsilonTransition(nfa1.end(), nfa1.start());

        return IntPair.create(start, end);

      case sym.QUESTION:
        nfa1 = insertNFA((RegExp) ((RegExp1) regExp).content);

        addEpsilonTransition(nfa1.start(), nfa1.end());

        return IntPair.create(nfa1.start(), nfa1.end());

      case sym.BANG:
        return complement(insertNFA((RegExp) ((RegExp1) regExp).content));

      case sym.TILDE:
        return insertNFA(regExp.resolveTilde());

      case sym.STRING:
        return insertStringNFA(false, (String) ((RegExp1) regExp).content);

      case sym.STRING_I:
        return insertStringNFA(true, (String) ((RegExp1) regExp).content);

      default:
        throw new RegExpException(regExp);
    }
  }