EventDecorator.java

@Decorates
abstract class BarEventDecorator implements Event<Bar>{

    @Inject @Delegate @Baz Event<Bar> d;

    void fire(Bar bar) {
       d.fire(bar);
    }

}

Foo.java

class Foo {

   @Inject Event<Bar> e;

   void doIt() {
      e.fire(new Bar());
   }

}