code: public CacheAdapter getOrCreate(Resource resource) {
  		CacheAdapter adapter = (CacheAdapter) EcoreUtil.getAdapter(resource.eAdapters(), CacheAdapter.class);
  		if (adapter == null) {
  			adapter = new CacheAdapter();
  			resource.eAdapters().add(adapter);
  			adapter.setResource(resource);
  		}
  		return adapter;
  	}
docs: Returns the cache adapter that is associated with the resource. The lifecycle of the cache
  is strongly connected to the resource and its change notifications. Will not return <code>null</code>.
  @param resource the resource. May not be <code>null</code>.
  @return the cache adapter for the given resource. Never <code>null</code>.