import java.util.*;

class State {

    protected State (String name) {

	_defaultTransition = null;
	_transitionList = null;
	_name = name;

    }

    public State (DefaultTransition defaultTransition, String name) {

	_defaultTransition = defaultTransition;
	_transitionList = new LinkedList();
	_name = name;

    }

    public String toString () {

	return _name;

    }

    public boolean success () {

	return false;

    }

    public boolean failure () {

	return false;

    }

    public State followTransition (char c) {

	// Iterate through the transition list, looking for one that
	// applies to this symbol.
	ListIterator i = null;
	try {
	    i = _transitionList.listIterator(0);
	} catch (IndexOutOfBoundsException e) {
	    i = null;
	}
	while (i != null) {

	    // Test the current transition.
	    Transition current = null;
	    try {
		current = (Transition)i.next();
	    } catch (NoSuchElementException e) {
		i = null;
		continue;
	    }

	    // Does this transition apply to the symbol?
	    if (current.testSymbol(c)) {
		return current.followTransition();
	    }

	}

	// No regular transition applies, so take the default.
	return _defaultTransition.followTransition();

    }

    protected boolean isRedundant (Transition transition) {

	// Iterate through the existing transitions.
	ListIterator i = null;
	try {
	    i = _transitionList.listIterator(0);
	} catch (IndexOutOfBoundsException e) {
	    i = null;
	}
	while (i != null) {

	    // Test the given transition against this one.
	    Transition current = null;
	    try {
		current = (Transition)i.next();
	    } catch (NoSuchElementException e) {
		i = null;
		continue;
	    }

	    // These two transitions cover the same symbol.
	    if (current.isRedundant(transition)) {
		return true;
	    }

	}

	// No redundancy.
	return false;

    }

    public void addTransition (Transition transition) {

	// Ensure that this transition does not cover a symbol already
	// covered by another transition.
	if (!isRedundant(transition)) {

	    _transitionList.add(transition);

	}

    }

    protected DefaultTransition _defaultTransition;
    protected LinkedList _transitionList;
    protected String _name;

}