Incorporate review comments and cleanup isAvailable, see #2018

* Renamed isRunning to isTerminated (with negation of course)
* Removed Running from JMX API, since the mbean is deregistered anyway
* Cleanup isAvailable, isUnavailbe
* Misc minor

akka-cluster/src/main/scala/akka/cluster/Cluster.scala

@@ -67,7 +67,7 @@ class Cluster(val system: ExtendedActorSystem) extends Extension {
         format(system, other.getClass.getName))
   }
 
-  private val _isRunning = new AtomicBoolean(true)
+  private val _isTerminated = new AtomicBoolean(false)
   private val log = Logging(system, "Cluster")
 
   log.info("Cluster Node [{}] - is starting up...", selfAddress)
@@ -169,9 +169,9 @@ class Cluster(val system: ExtendedActorSystem) extends Extension {
   // ======================================================
 
   /**
-   * Returns true if the cluster node is up and running, false if it is shut down.
+   * Returns true if this cluster instance has be shutdown.
    */
-  def isRunning: Boolean = _isRunning.get
+  def isTerminated: Boolean = _isTerminated.get
 
   /**
    * Subscribe to cluster domain events.
@@ -253,7 +253,7 @@ class Cluster(val system: ExtendedActorSystem) extends Extension {
    * to go through graceful handoff process `LEAVE -> EXITING -> REMOVED -> SHUTDOWN`.
    */
   private[cluster] def shutdown(): Unit = {
-    if (_isRunning.compareAndSet(true, false)) {
+    if (_isTerminated.compareAndSet(false, true)) {
       log.info("Cluster Node [{}] - Shutting down cluster Node and cluster daemons...", selfAddress)
 
       system.stop(clusterDaemons)

akka-cluster/src/main/scala/akka/cluster/ClusterDaemon.scala

@@ -763,7 +763,7 @@ private[cluster] final class ClusterCoreDaemon(publisher: ActorRef) extends Acto
 
   def isSingletonCluster: Boolean = latestGossip.isSingletonCluster
 
-  def isAvailable: Boolean = latestGossip.isAvailable(selfAddress)
+  def isAvailable: Boolean = !latestGossip.isUnreachable(selfAddress)
 
   /**
    * Gossips latest gossip to a random member in the set of members passed in as argument.

akka-cluster/src/main/scala/akka/cluster/ClusterJmx.scala

@@ -24,11 +24,13 @@ trait ClusterNodeMBean {
 
   /**
    * Comma separated addresses of member nodes, sorted in the cluster ring order.
+   * The address format is `akka://actor-system-name@hostname:port`
    */
   def getMembers: String
 
   /**
    * Comma separated addresses of unreachable member nodes.
+   * The address format is `akka://actor-system-name@hostname:port`
    */
   def getUnreachable: String
 
@@ -46,6 +48,7 @@ trait ClusterNodeMBean {
 
   /**
    * Get the address of the current leader.
+   * The address format is `akka://actor-system-name@hostname:port`
    */
   def getLeader: String
 
@@ -55,25 +58,27 @@ trait ClusterNodeMBean {
   def isSingleton: Boolean
 
   /**
-   * Returns true if the node is UP or JOINING.
+   * Returns true if the node is not unreachable and not `Down`
+   * and not `Removed`.
    */
   def isAvailable: Boolean
-  /**
-   * Returns true if the cluster node is up and running, false if it is shut down.
-   */
-  def isRunning: Boolean
 
   /**
    * Try to join this cluster node with the node specified by 'address'.
+   * The address format is `akka://actor-system-name@hostname:port`.
    * A 'Join(thisNodeAddress)' command is sent to the node to join.
    */
   def join(address: String)
+
   /**
    * Send command to issue state transition to LEAVING for the node specified by 'address'.
+   * The address format is `akka://actor-system-name@hostname:port`
    */
   def leave(address: String)
+
   /**
    * Send command to DOWN the node specified by 'address'.
+   * The address format is `akka://actor-system-name@hostname:port`
    */
   def down(address: String)
 }
@@ -109,14 +114,12 @@ private[akka] class ClusterJmx(cluster: Cluster, log: LoggingAdapter) {
 
       def getMemberStatus: String = clusterView.status.toString
 
-      def getLeader: String = clusterView.leader.getOrElse("").toString
+      def getLeader: String = clusterView.leader.fold("")(_.toString)
 
       def isSingleton: Boolean = clusterView.isSingletonCluster
 
       def isAvailable: Boolean = clusterView.isAvailable
 
-      def isRunning: Boolean = clusterView.isRunning
-
       // JMX commands
 
       def join(address: String) = cluster.join(AddressFromURIString(address))

akka-cluster/src/main/scala/akka/cluster/ClusterReadView.scala

@@ -74,9 +74,9 @@ private[akka] class ClusterReadView(cluster: Cluster) extends Closeable {
   }
 
   /**
-   * Returns true if the cluster node is up and running, false if it is shut down.
+   * Returns true if this cluster instance has be shutdown.
    */
-  def isRunning: Boolean = cluster.isRunning
+  def isTerminated: Boolean = cluster.isTerminated
 
   /**
    * Current cluster members, sorted by address.
@@ -118,11 +118,14 @@ private[akka] class ClusterReadView(cluster: Cluster) extends Closeable {
   def convergence: Boolean = state.convergence
 
   /**
-   * Returns true if the node is UP or JOINING.
+   * Returns true if the node is not unreachable and not `Down`
+   * and not `Removed`.
    */
   def isAvailable: Boolean = {
     val myself = self
-    !unreachableMembers.contains(myself) && !myself.status.isUnavailable
+    !unreachableMembers.contains(myself) &&
+      myself.status != MemberStatus.Down &&
+      myself.status != MemberStatus.Removed
   }
 
   /**

akka-cluster/src/main/scala/akka/cluster/Gossip.scala

@@ -168,15 +168,10 @@ private[cluster] case class Gossip(
   def isSingletonCluster: Boolean = members.size == 1
 
   /**
-   * Returns true if the node is UP or JOINING.
+   * Returns true if the node is in the unreachable set
    */
-  def isAvailable(address: Address): Boolean = !isUnavailable(address)
+  def isUnreachable(address: Address): Boolean =
-
+    overview.unreachable exists { _.address == address }
-  def isUnavailable(address: Address): Boolean = {
-    val isUnreachable = overview.unreachable exists { _.address == address }
-    val hasUnavailableMemberStatus = members exists { m ⇒ m.status.isUnavailable && m.address == address }
-    isUnreachable || hasUnavailableMemberStatus
-  }
 
   def member(address: Address): Member = {
     members.find(_.address == address).orElse(overview.unreachable.find(_.address == address)).

akka-cluster/src/main/scala/akka/cluster/Member.scala

@@ -87,13 +87,7 @@ object Member {
  *
  * Can be one of: Joining, Up, Leaving, Exiting and Down.
  */
-abstract class MemberStatus extends ClusterMessage {
+abstract class MemberStatus extends ClusterMessage
-
-  /**
-   * Using the same notion for 'unavailable' as 'non-convergence': DOWN
-   */
-  def isUnavailable: Boolean = this == Down
-}
 
 object MemberStatus {
   case object Joining extends MemberStatus

akka-cluster/src/multi-jvm/scala/akka/cluster/LeaderLeavingSpec.scala

@@ -57,7 +57,7 @@ abstract class LeaderLeavingSpec
           enterBarrier("leader-left")
 
           // verify that the LEADER is shut down
-          awaitCond(!cluster.isRunning)
+          awaitCond(cluster.isTerminated)
 
           // verify that the LEADER is REMOVED
           awaitCond(clusterView.status == Removed)

akka-cluster/src/multi-jvm/scala/akka/cluster/MBeanSpec.scala

@@ -45,7 +45,7 @@ abstract class MBeanSpec
     "expose attributes" taggedAs LongRunningTest in {
       val info = mbeanServer.getMBeanInfo(mbeanName)
       info.getAttributes.map(_.getName).toSet must be(Set(
-        "ClusterStatus", "Members", "Unreachable", "MemberStatus", "Leader", "Singleton", "Available", "Running"))
+        "ClusterStatus", "Members", "Unreachable", "MemberStatus", "Leader", "Singleton", "Available"))
       enterBarrier("after-1")
     }
 
@@ -58,8 +58,7 @@ abstract class MBeanSpec
 
     "change attributes after startup" taggedAs LongRunningTest in {
       runOn(first) {
-        mbeanServer.getAttribute(mbeanName, "Running").asInstanceOf[Boolean] must be(true)
+        mbeanServer.getAttribute(mbeanName, "Available").asInstanceOf[Boolean] must be(false)
-        mbeanServer.getAttribute(mbeanName, "Available").asInstanceOf[Boolean] must be(true)
         mbeanServer.getAttribute(mbeanName, "Singleton").asInstanceOf[Boolean] must be(false)
         mbeanServer.getAttribute(mbeanName, "Leader") must be("")
         mbeanServer.getAttribute(mbeanName, "Members") must be("")
@@ -73,6 +72,7 @@ abstract class MBeanSpec
         mbeanServer.getAttribute(mbeanName, "Singleton").asInstanceOf[Boolean] must be(true)
         mbeanServer.getAttribute(mbeanName, "Members") must be(address(first).toString)
         mbeanServer.getAttribute(mbeanName, "Unreachable") must be("")
+        mbeanServer.getAttribute(mbeanName, "Available").asInstanceOf[Boolean] must be(true)
       }
       enterBarrier("after-3")
     }
@@ -134,7 +134,7 @@ abstract class MBeanSpec
         awaitCond(mbeanServer.getAttribute(mbeanName, "Members") == expectedMembers)
       }
       runOn(third) {
-        awaitCond(!cluster.isRunning)
+        awaitCond(cluster.isTerminated)
         // mbean should be unregistered, i.e. throw InstanceNotFoundException
         awaitCond(Try { mbeanServer.getMBeanInfo(mbeanName); false } recover {
           case e: InstanceNotFoundException ⇒ true

akka-cluster/src/multi-jvm/scala/akka/cluster/NodeLeavingAndExitingAndBeingRemovedSpec.scala

@@ -51,7 +51,7 @@ abstract class NodeLeavingAndExitingAndBeingRemovedSpec
 
       runOn(second) {
         // verify that the second node is shut down and has status REMOVED
-        awaitCond(!cluster.isRunning, reaperWaitingTime)
+        awaitCond(cluster.isTerminated, reaperWaitingTime)
         awaitCond(clusterView.status == MemberStatus.Removed, reaperWaitingTime)
       }
 

akka-docs/rst/cluster/cluster-usage-java.rst

@@ -581,7 +581,6 @@ Run it without parameters to see instructions about how to use the script::
                 is-singleton - Checks if the cluster is a singleton cluster (single
                                node cluster)
                 is-available - Checks if the member node is available
-                  is-running - Checks if the member node is running
   Where the <node-url> should be on the format of 
     'akka://actor-system-name@hostname:port'
 

akka-docs/rst/cluster/cluster-usage-scala.rst

@@ -587,7 +587,6 @@ Run it without parameters to see instructions about how to use the script::
                 is-singleton - Checks if the cluster is a singleton cluster (single
                                node cluster)
                 is-available - Checks if the member node is available
-                  is-running - Checks if the member node is running
   Where the <node-url> should be on the format of 
     'akka://actor-system-name@hostname:port'
 

akka-kernel/src/main/dist/bin/akka-cluster

@@ -168,19 +168,6 @@ case "$2" in
         $JMX_CLIENT $HOST akka:type=Cluster Available
         ;;
 
-    is-running)
-        if [ $# -ne 2 ]; then
-            echo "Usage: $SELF <node-hostname:jmx-port> is-running"
-            exit 1
-        fi
-
-        ensureNodeIsRunningAndAvailable
-        shift
-
-        echo "Checking if member node on $HOST is RUNNING"
-        $JMX_CLIENT $HOST akka:type=Cluster Running
-        ;;
-
     *)
         printf "Usage: bin/$SELF <node-hostname:jmx-port> <command> ...\n"
         printf "\n"
@@ -195,7 +182,6 @@ case "$2" in
         printf "%26s - %s\n" leader              "Asks the cluster who the current leader is"
         printf "%26s - %s\n" is-singleton        "Checks if the cluster is a singleton cluster (single node cluster)"
         printf "%26s - %s\n" is-available        "Checks if the member node is available"
-        printf "%26s - %s\n" is-running          "Checks if the member node is running"
         printf "Where the <node-url> should be on the format of 'akka://actor-system-name@hostname:port'\n"
         printf "\n"
         printf "Examples: bin/$SELF localhost:9999 is-available\n"