public void Monitor(PullMessageCommandV2 cmd)
 {
     if (cmd != null)
     {
         cmds[cmd.Header.CorrelationId] = cmd;
     }
 }
 public void Remove(PullMessageCommandV2 cmd)
 {
     PullMessageCommandV2 removedCmd = null;
     if (cmd != null)
     {
         cmds.TryRemove(cmd.Header.CorrelationId, out removedCmd);
     }
 }