No ID Attribute with UUIDs

[randomnamehmm]

Hello. I have the follow problem:

When I use the JsonUuidResource as shown in this code
ResourceSet resourceSet = new ResourceSetImpl(); resourceSet.getResourceFactoryRegistry().getExtensionToFactoryMap() .put("json", new JsonResourceFactory() { @Override public Resource createResource(URI uri) { return new JsonResource(uri, getMapper()) { @Override protected boolean useUUIDs() { return true; } }; } });

and save some EObjects to a JSON, they don't have an "id" attribute containing the UUID.
Yet they are referenced by other EObjects with "ref" : "MY_UUID".
Is this a bug or do I have to do something else in order to show ids?

Thanks.