RxJava2 setCancellable vs do最后

Question

在与setCancellable相同的所有情况下，是否会调用doFinally中的操作？在下面的示例中，我可以只使用setCancellable，还是doFinally涵盖更多情况？

var closeable: Closeable? = null

Flowable.defer {
    Flowables.create<Closeable>(BackpressureStrategy.BUFFER) { emitter ->
        val c = getCloseable()

        emitter.setCancellable { c.close() }

        if(!emitter.isCancelled) emitter.onNext(c)
    }
    .doFinally { closeable?.close() }
}