public AutomatonSpecification createFixedAutomaton() {
AutomatonSpecification automaton = new NaiveAutomatonSpecification();
State q0 = automaton.addState();
State q1 = automaton.addState();
automaton.addTransition(q0, q1,
new CharClassTransitionLabel(charClass));
automaton.markAsInitial(q0);
automaton.markAsFinal(q1);
return automaton;
}