public EntityhubConfiguration(ValueFactory vf){
super();
vf = vf == null ? InMemoryValueFactory.getInstance() : vf;
//register special Entutyhub Transformer for
// * entityhub:reference
ValueConverter<Reference> referenceConverter = new ReferenceConverter();
addTransformer(referenceConverter.getDataType(),
new ValueConverterTransformerAdapter<Reference>(referenceConverter,vf));
// * xsd:anyURI
ValueConverter<Reference> uriConverter = new AnyUriConverter();
addTransformer(uriConverter.getDataType(),
new ValueConverterTransformerAdapter<Reference>(uriConverter,vf));