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HermiT is reasoner for ontologies written using the Web Ontology Language (OWL). Given an OWL file, HermiT can determine whether or not the ontology is consistent, identify subsumption relationships between classes, and much more. This is the maven build of HermiT and is designed for people who wish to use HermiT from within the OWL API. It is now versioned in the main HermiT version repository, although not officially supported by the HermiT developers. The version number of this package is a composite of the HermiT version and an value representing releases of this packaged version. So, 1.3.7.1 is the first release of the mavenized version of HermiT based on the 1.3.7 release of HermiT. This package includes the Jautomata library (http://jautomata.sourceforge.net/), and builds with it directly. This library appears to be no longer under active development, and so a "fork" seems appropriate. No development is intended or anticipated on this code base.

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/**
 * 
 */
package rationals.transformations;

import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;

import rationals.Automaton;
import rationals.NoSuchStateException;
import rationals.State;
import rationals.Transition;

/**
 * A (rational) substitution is a  morphism that maps
 * letters to languages.
 * A rational substitution is constructed like a {@see rationals.transformations.Morphism}
 * with an instance of {@see java.util.Map} that has Object as 
 * keys and either Object or Automaton instances as values.
 * If the value of a key is an object, then it is  considered a letter 
 * and this class acts like a morphism. If the value of the key is an
 * Automaton, then the complete transition is replaced by the language
 * denoted by the automaton.
 * 
 * @author nono
 * @see J.Berstel, "Transductions and context-free languages"
 */
public class Substitution implements UnaryTransformation {

	private Map morph;

	public Substitution(Map m) {
		this.morph = m;
	}

	/* (non-Javadoc)
	 * @see rationals.transformations.UnaryTransformation#transform(rationals.Automaton)
	 */
	public Automaton transform(Automaton a) {
		Automaton b = new Automaton();
		/* state map */
		Map stm = new HashMap();
		for (Iterator i = a.delta().iterator(); i.hasNext();) {
			Transition tr = (Transition) i.next();
			State ns = tr.start();
			State nss = (State) stm.get(ns);
			if (nss == null) {
				nss = b.addState(ns.isInitial(), ns.isTerminal());
				stm.put(ns, nss);
			}
			State ne = tr.end();
			State nse = (State) stm.get(ne);
			if (nse == null) {
				nse = b.addState(ne.isInitial(), ne.isTerminal());
				stm.put(ne, nse);
			}
			Object lbl = tr.label();
			if (!morph.containsKey(lbl))
				try {
					b.addTransition(new Transition(nss, lbl, nse));
				} catch (NoSuchStateException e) {
				}
			else
				try {
					/* is value an automaton ? */
					Object o = morph.get(lbl);
					if (o instanceof Automaton)
						insert(nss, nse, b, (Automaton) o);
					else
						b
								.addTransition(new Transition(nss, morph
										.get(lbl), nse));
				} catch (NoSuchStateException e1) {
				}
		}
		return b;
	}

	/**
	 * Insert automaton between states nss and
	 * nse in automaton b.
	 * This method add epsilon transitions from nss to each starting 
	 * state of automaton and from each ending state to nse.
	 * 
	 * @param nss
	 * @param nse
	 * @param b
	 * @param automaton
	 */

	private void insert(State nss, State nse, Automaton b, Automaton automaton) {
		/* map states */
		Map map = new HashMap();
		for (Iterator i = automaton.states().iterator(); i.hasNext();) {
			State e = (State) i.next();
			State n = b.addState(false, false);
			map.put(e, n);
			if (e.isInitial())
				try {
					b.addTransition(new Transition(nss, null, n));
				} catch (NoSuchStateException e1) {
				}
			if (e.isTerminal())
				try {
					b.addTransition(new Transition(n, null, nse));
				} catch (NoSuchStateException e1) {
				}

		}
		for (Iterator i = automaton.delta().iterator(); i.hasNext();) {
			Transition t = (Transition) i.next();
			try {
				b.addTransition(new Transition((State) map.get(t.start()), t
						.label(), (State) map.get(t.end())));
			} catch (NoSuchStateException x) {
			}
		}

	}

}