code: public void onChange(TopologyChangeEvent event)
     {
        try
        {
           if (rpcService.isCoordinator() && !isOnline)
           {
              new Thread()
              {
                 @Override
                 public synchronized void run()
                 {
                    try
                    {
                       List<Object> results =
                          rpcService.executeCommandOnAllNodes(requestForResponsibleToSetIndexOnline, true);
  
                       for (Object result : results)
                       {
                          if (result instanceof Boolean)
                          {
                             if ((Boolean)result)
                             {
                                return;
                             }
                          }
                          else
                          {
                             log.error("Result is not an instance of Boolean" + result);
                          }
                       }
                       // node which was responsible for resuming leave the cluster, so resume component
                       log
                          .error("Node responsible for setting index back online seems to leave the cluster. Setting back online.");
                       searchManager.setOnline(true, false, false);
                    }
                    catch (SecurityException e1)
                    {
                       log.error("You haven't privileges to execute remote command", e1);
                    }
                    catch (RPCException e1)
                    {
                       log.error("Exception during command execution", e1);
                    }
                    catch (IOException e2)
                    {
                       log.error("Exception during setting index back online", e2);
                    }
                 }
              }.start();
           }
        }
        catch (RPCException e)
        {
           log.error("Can't check if node coordinator or not.");
        }
     }
docs: {@inheritDoc}