documentProcessors.getProcessor(Composite.class);
documentProcessors.addArtifactProcessor(new CompositeDocumentProcessor(staxProcessor, validatingInputFactory,
documentBuilderFactory, policyDefinitions, monitor));
// Create Model Resolver extension point
ModelResolverExtensionPoint modelResolvers = registry.getExtensionPoint(ModelResolverExtensionPoint.class);
// Create contribution package processor extension point
TypeDescriber describer = new PackageTypeDescriberImpl();
PackageProcessor packageProcessor =
new ExtensiblePackageProcessor(registry.getExtensionPoint(PackageProcessorExtensionPoint.class), describer,