refCount() with delay doesn't support multicasting

RxJava Version: 2.2.13

Suppose multiple observers subscribe with some delay between each subscription then refCount() is not supporting Multicasting. Below is the sample for this scenario

Code Sample

val observable = Observable.range(1, 3)
            .subscribeOn(Schedulers.io())
            .map(object : Function<Int, Int> {
                override fun apply(input: Int): Int {
                    println("Inside map operator Squaring the input")
                    return input * input
                }
            })

val refCountObservable = observable.publish().refCount()
println("Wait for 3 seconds for observer1 to subscribe")
Thread.sleep(3000)
refCountObservable.subscribe(observer1)
println("Wait for 3 seconds for observer2 to subscribe")
Thread.sleep(3000)
refCountObservable.subscribe(observer2)

Output

Wait for 3 seconds for observer1 to subscribe
Observer1 onSubscribe
Wait for 3 seconds for observer2 to subscribe
Inside map operator Squaring the input
Observer1 Output 1
Inside map operator Squaring the input
Observer1 Output 4
Inside map operator Squaring the input
Observer1 Output 9
Observer1 onComplete
Observer2 onSubscribe
Inside map operator Squaring the input
Observer2 Output 1
Inside map operator Squaring the input
Observer2 Output 4
Inside map operator Squaring the input
Observer2 Output 9
Observer2 onComplete

In the above output, you can see the map operator is called for the two observers instead of doing Multicasting.

[akarnokd]

Again, refCount starts over if the source completes. Timeout after a completed source has no effect. Even if it delayed a reconnection, you’d not get items for Observer2 because publish requires live audience while it emits its values.

[harisudhan7889]

@akarnokd Thanks for the clarification.