public static GraphMatcher match(String ruleXMLFile, String hostXMLFile,
MatchCallback callback) throws Exception {
MoMLParser parser = new MoMLParser();
TransformationRule rule = (TransformationRule) parser.parse(null,
new File(ruleXMLFile).toURI().toURL());
parser.reset();
CompositeEntity host = (CompositeEntity) parser.parse(null, new File(
hostXMLFile).toURI().toURL());
GraphMatcher matcher = new GraphMatcher();
if (callback != null) {