Small snippet to check which thread an rxjava observable is requesting/returning on

rxjavathreadtest.java

    @Test
    public void testRxjavaThreading() throws InterruptedException {
        final BlockingQueue<Runnable> tasks = new LinkedBlockingQueue<>();
        System.out.println("Caller thread: " + Thread.currentThread().getName());

        final Disposable subscribe = Observable.fromCallable(
                new Callable<Integer>() {
                    @Override
                    public Integer call() throws Exception {
                        System.out.println("Observable thread: " + Thread.currentThread().getName());
                        return 1;
                    }
                })
                .subscribeOn(Schedulers.single())
                .observeOn(AndroidSchedulers.mainThread())
                .subscribe(new Consumer<Integer>() {
                    @Override
                    public void accept(@NonNull Integer integer) throws Exception {
                        System.out.println("Observer thread: " + Thread.currentThread().getName());
                    }
                });
        tasks.take().run();
        subscribe.dispose();
        assertTrue(true);
    }