class SimpleController implements IReferenceable, IUnreferenceable {
  ...
      public setReferences(references) {
          this._worker = this._references.getOneRequired(
              new Descriptor("*", "worker", "worker1", "*", "1.0")
          );
      }
  ...
  }
  
let references = References.fromTuples(
    new Descriptor("sample", "worker", "worker1", "111", "1.0"), new Worker1("name1"),
    new Descriptor("sample", "worker", "worker2", "222", "1.0"), new Worker2("name1")
);

let controller = new SimpleController();
controller.setReferences(references);
controller.greeting("world");
controller.unsetReferences();
controller = null;