RXJava 1.3-AMB不订阅或取消订阅较慢的流

    Observable<Object> obs1 = Observable
            .create(subscriber -> subscriber.onNext("obs 1 event"))
            .doOnSubscribe(() -> System.out.println("obs1 sub"))
            .doOnUnsubscribe(() -> System.out.println("obs1 unsub"));

    Observable<Object> obs2 = Observable
            .create(subscriber -> subscriber.onNext("obs 2 event"))
            .doOnSubscribe(() -> System.out.println("obs2 sub"))
            .doOnUnsubscribe(() -> System.out.println("obs2 unsub"));

    Observable
            .amb(obs1, obs2)
            .subscribe(System.out::println);

    Thread.sleep(500);

应该调用obs2 doon*方法,并且应该只发出两个事件中的一个。程序输出:

obs1 sub
obs 1 event

没有调用obs2的*订阅方法。