RxJava single background thread scheduler

You can create a single reusable thread to create a Scheduler for the Observable in one of the following ways:

Create a ThreadPoolExecuter with a pool size of 1 (Executors.newSingleThreadExecutor() is a convenient static factory method for doing that), then use it to generate the schedulers via the Schedulers.from() method.
RxAndroid provides a custom Scheduler implementation that uses a Handler to schedule the actions, and thus can be used with any Thread that has a Looper running by passing it's Handler to the AndroidSchedulers.handlerThread() factory method.

Note that you will need to observe on a main thread Scheduler if you're interacting with the UI at the conclusion of these tasks.

In RxJava 2 you can use Schedulers.single() which:

Returns a default, shared, single-thread-backed Scheduler instance for work requiring strongly-sequential execution on the same background thread.

Please see the documentation for more details.

I don't see it available in RxJava 1 Schedulers documentation.

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