code: public void setMatchspaceSub(ControllableProxySubscription sub)
    {
      if (TraceComponent.isAnyTracingEnabled() && tc.isEntryEnabled()) 
        SibTr.entry(tc, "setMatchspaceSub", sub);
      
      _controllableProxySubscription = sub;
      
      if (TraceComponent.isAnyTracingEnabled() && tc.isEntryEnabled()) 
        SibTr.exit(tc, "setMatchspaceSub");
    }
docs: This sets the field in the MESubscription for the object that was
  stored in the Matchspace
  @param sub