Akka dispatcher with configurable priority for created threads.

PriorityThreadsDispatcher.scala

package akka.dispatch

import com.typesafe.config.Config

object PriorityThreadsDispatcher {
  /**
   * Configuration key under which int value should be placed.
   */
  val threadPriorityConfigKey = "thread-priority"
}

/**
 * Akka Dispatcher that creates thread with configurable priority.
 *
 * Example of configuration:
 *
 *   low-priority-threads-dispatcher {
 *     type = akka.dispatch.PriorityThreadsDispatcher
 *     executor = "thread-pool-executor"
 *     threads-priority = 1  <--- here we set the priority, should be between Thread.MIN_PRIORITY (which is 1) and Thread.MAX_PRIORITY (which is 10)
 *     thread-pool-executor {
 *       core-pool-size-min = 0
 *       core-pool-size-factor = 2.0
 *       core-pool-size-max = 10
 *     }
 *   }
 *
 * Two arguments constructor (the primary constructor) is automatically called by Akka when it founds:
 *   abcde-dispatcher {
 *     type = akka.dispatch.PriorityThreadsDispatcher <--- that is a class that Akka will instantiate
 *     ...
 *   }
 *
 * @param config passed automatically by Akka, should contains information about threads priority
 * @param prerequisites passed automatically by Akka
 */
class PriorityThreadsDispatcher(config: Config, prerequisites: DispatcherPrerequisites)
  extends DispatcherConfigurator(config, new PriorityThreadsDispatcherPrerequisites(prerequisites, config.getInt(PriorityThreadsDispatcher.threadPriorityConfigKey)))