protected boolean memberJoined(Address joinAddress, ClusterNode clusterNode) {

    _liveInstances.put(joinAddress, clusterNode);

    Address previousAddress =
        _clusterNodeAddresses.put(clusterNode.getClusterNodeId(), joinAddress);

    if (previousAddress != null) {
      return false;
    }

    ClusterEvent clusterEvent = ClusterEvent.join(clusterNode);

    fireClusterEvent(clusterEvent);

    return true;
  }
 protected void processClusterEvent() {
   _replicasClusterListener.processClusterEvent(ClusterEvent.join());
 }