Learning RxJava - Second Edition

Turning Observable into Flowable and vice versa

There is another way to implement BackpressureStrategy against a source that has no notion of backpressure. You can turn an Observable into Flowable by calling its toFlowable() operator, which accepts a BackpressureStrategy as an argument. In the following code, we turn Observable.range() into Flowable using BackpressureStrategy.BUFFER. An Observable has no notion of backpressure, so it is going to push items as quickly as it can, regardless of whether the downstream can keep up. But toFlowable(), with a buffering strategy, will act as a proxy to backlog the emissions when the downstream cannot keep up:

import io.reactivex.rxjava3.core.BackpressureStrategy;import io.reactivex.rxjava3.core.Observable; ...