In this code snippet, a ThreadPoolExecutor is statically saved within a singleton object with Dagger 2.

TopologicalProcessor.kt

import java.util.concurrent.*

private val threadFactory = object : ThreadFactory {
    private val count = AtomicInteger(1)
    override fun newThread(r: Runnable): Thread = Thread(r, "Thread #${count.getAndIncrement()}")
}

@Singleton
class TopologicalProcessor {
    
    /* Removed for brevity */
    companion object {
        var tileMapThreadPoolExecutor = ThreadPoolExecutor(
            corePoolSize = 3,
            maximumPoolSize = 3, 
            keepAliveTime = 0L, 
            unit = TimeUnit.SECONDS,
            workQueue = LinkedBlockingQueue<Runnable>(),
            threadFactory = threadFactory
        )
    }
}