RxRelays are awesome 1

rxRelayAwesome1.java

public abstract class RxStore<Input, Output> {
    private BehaviorRelay<Output> relay = BehaviorRelay.create(defaultValue());

    public final Subscription register(Subscriber<Output> subscriber) {
        return relay.subscribe(subscriber);
    }

    public final void execute(Input event) {
        buildObservable(event).subscribe(relay);
    }

    protected Output defaultValue() { return null; }
    protected abstract Observable<Output> buildObservable(Input event);
}