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36 package gr.grnet.aquarium.actor
40 import org.apache.solr.util.ConcurrentLRUCache
41 import akka.actor.ActorRef
42 import gr.grnet.aquarium.util.{Loggable, Lifecycle}
43 import collection.JavaConversions._
46 * This class holds an LRU cache for the user actors.
48 * The underlying implementation is borrowed from the Apache lucene+solr project(s).
50 * The provided collections-like API is neither Java- nor Scala-oriented.
52 * @author Christos KK Loverdos <loverdos@gmail.com>
55 class UserActorsLRU(val upperWaterMark: Int, val lowerWatermark: Int) extends Lifecycle {
56 private[this] val _cache = new ConcurrentLRUCache[String, ActorRef](
59 ((upperWaterMark + lowerWatermark).toLong / 2).toInt,
60 (3L * upperWaterMark / 4).toInt,
65 def put(userId: String, userActor: ActorRef): Unit = {
66 _cache.put(userId, userActor)
69 def get(userId: String): Option[ActorRef] = {
70 _cache.get(userId) match {
72 case actorRef ⇒ Some(actorRef)
77 val accessed = mapAsScalaMap(_cache.getLatestAccessedItems(_cache.size()))
79 //Send the poison pill and make sure that all futures have been returned
80 accessed.keysIterator.map {
82 UserActorSupervisor.supervisor.unlink(_cache.get(x))
87 def size: Int = _cache.size()
89 def clear: Unit = _cache.clear()
97 private[this] object EvictionListener extends ConcurrentLRUCache.EvictionListener[String, ActorRef] with Loggable {
98 def evictedEntry(userId: String, userActor: ActorRef): Unit = {
99 logger.debug("Parking UserActor for userId = %s".format(userId))
100 UserActorSupervisor.supervisor.unlink(userActor)
101 // Check this is received after any currently servicing business logic message.
103 // Hopefully no need to further track these actors as they will now cause their own death.