LoggingScheduledThreadPoolExecutor.scala

class LoggingScheduledThreadPoolExecutor(nthreads: Int)
    extends ScheduledThreadPoolExecutor(nthreads) {

    private val log = Logger(LoggerFactory.getLogger(classOf[LoggingScheduledThreadPoolExecutor]))

    override def submit[T](task: Runnable, result: T): java.util.concurrent.Future[T] = {
        val queueTime = System.nanoTime()
        log debug s"Submit task $task"

        super.submit(new Runnable {
            override def run(): Unit = {
                val startTime = System.nanoTime()
                val timeWaiting = (startTime - queueTime) / 1000000
                log debug s"Starting task $task after $timeWaiting ms in queue"
                task.run()
                val tookTime = (System.nanoTime() - startTime) / 1000000
                log debug s"Finished task $task took $tookTime ms"
            }
        },result)
    }

    override def submit(task: Runnable): java.util.concurrent.Future[_] = {
        val queueTime = System.nanoTime()
        log debug s"Submit task $task"

        super.submit(new Runnable {
            override def run(): Unit = {
                val startTime = System.nanoTime()
                val timeWaiting = (startTime - queueTime) / 1000000
                log debug s"Starting task $task after $timeWaiting ms in queue"
                task.run()
                val tookTime = (System.nanoTime() - startTime) / 1000000
                log debug s"Finished task $task took $tookTime ms"
            }
        })
    }

    override def submit[T](task: Callable[T]): java.util.concurrent.Future[T] = {
        val queueTime = System.nanoTime()
        log debug s"Submit task $task"

        super.submit(new Callable[T] {
            override def call(): T = {
                val startTime = System.nanoTime()
                val timeWaiting = (startTime - queueTime) / 1000000
                log debug s"Starting callable $task after $timeWaiting ms in queue"
                val result = task.call()
                val tookTime = (System.nanoTime() - startTime) / 1000000
                log debug s"Finished callable $task took $tookTime ms"
                result
            }
        })
    }
}