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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;
import rationals.properties.ContainsEpsilon;

/**
 * A transformation that normalizes a given Automaton.
 * 
 * This transformation produces a new Automaton with the following features :
 * 

 * it has one start state and one end state,
 * there is no incoming (resp. outgoing) transitions to (resp. from) the
 * start (resp. end) state,
 * the resultant automaton is then pruned ({@link Pruner}) to remove
 * inaccessible states.
 * 
 * 
 * @author yroos
 * @version $Id: Normalizer.java 2 2006-08-24 14:41:48Z oqube $
 */
public class Normalizer implements UnaryTransformation {

    public Automaton transform(Automaton a) {
        Automaton b = new Automaton();
        State ni = b.addState(true, false);
        State nt = b.addState(false, true);
        Map map = new HashMap();
        Iterator i = a.states().iterator();
        while (i.hasNext()) {
            State st = (State) i.next();
            map.put(st, b.addState(false, false));
        }
        /* add epsilon transition if contains epsilon */
        if (new ContainsEpsilon().test(a))
            try {
                b.addTransition(new Transition(ni, null, nt));
            } catch (NoSuchStateException e) {
            }
        i = a.delta().iterator();
        while (i.hasNext()) {
            Transition t = (Transition) i.next();
            if (t.start().isInitial() && t.end().isTerminal()) {
                try {
                    b.addTransition(new Transition(ni, t.label(), nt));
                } catch (NoSuchStateException x) {
                }
            }
            if (t.start().isInitial()) {
                try {
                    b.addTransition(new Transition(ni, t.label(), (State) map
                            .get(t.end())));
                } catch (NoSuchStateException x) {
                }
            }

            if (t.end().isTerminal())
                try {
                    b.addTransition(new Transition((State) map.get(t.start()),
                            t.label(), nt));
                } catch (NoSuchStateException x) {
                }

            try {
                b.addTransition(new Transition((State) map.get(t.start()), t
                        .label(), (State) map.get(t.end())));
            } catch (NoSuchStateException x) {
            }

        }
        b = new Pruner().transform(b);
        return b;
    }
}

/*
 * $Log: Normalizer.java,v $ Revision 1.4 2005/02/20 21:14:19 bailly added API
 * for computing equivalence relations on automata
 * 
 * Revision 1.3 2004/09/21 11:50:28 bailly added interface BinaryTest added
 * class for testing automaton equivalence (isomorphism of normalized automata)
 * added computation of RE from Automaton
 *  
 */