code: private void refreshEffectiveTopology() throws ParentDeadException {
      LOG.entering("OperatorTopologyImpl", "refreshEffectiveTopology", getQualifiedName());
      LOG.finest(getQualifiedName() + "Waiting to acquire topoLock");
      synchronized (topologyLock) {
        LOG.finest(getQualifiedName() + "Acquired topoLock");
  
        assert effectiveTopology != null;
  
        final Set<GroupCommunicationMessage> deletionDeltasSet = new HashSet<>();
        copyDeletionDeltas(deletionDeltasSet);
  
        LOG.finest(getQualifiedName() + "Updating effective topology struct with deletion msgs");
        effectiveTopology.update(deletionDeltasSet);
        LOG.finest(getQualifiedName() + "Released topoLock");
      }
      LOG.exiting("OperatorTopologyImpl", "refreshEffectiveTopology", getQualifiedName());
    }
docs: Only refreshes the effective topology with deletion msgs from.
  deletionDeltas queue
  
  @throws ParentDeadException