multithreading - java Firebase: delay exit until writes finish

Question

I have a server written in Java that can receive a shut down signal while it's listening to, processing, and updating Firebase data. Since the Firebase threads are daemon threads in Java, I wanted to add some delay to the main thread to allow write operations to complete.

My current idea is the latch approach: use some concurrent counter to track pending writing operations, and let the main thread exit when there are none. The counter would get updated in onComplete() callbacks, so I was wondering:

In the Firebase client, when might onComplete() callbacks never get called? Is there reasonable danger of deadlock?

Answer 1

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