code: public synchronized ProxyQueueConversationGroup create(Conversation conversation)
        throws IllegalArgumentException
     {
        if (TraceComponent.isAnyTracingEnabled() && tc.isEntryEnabled()) SibTr.entry(tc, "create", conversation);
        
        if (convToGroupMap.containsKey(conversation))
        {
           // A proxy queue conversation group is associated one-to-one with a conversation. In this
           // case someone has tried to create 2 for the same conversation.
           SIErrorException e = new SIErrorException(
              nls.getFormattedMessage("PQGROUP_ALREADY_CREATED_SICO1054", null, null)
           );
              
           FFDCFilter.processException(e, CLASS_NAME + ".create",
                                       CommsConstants.PQCONVGRPFACTIMPL_CREATE_01, this);
           
           throw e;
        }
        
        ProxyQueueConversationGroup group =
           new ProxyQueueConversationGroupImpl(conversation, this);
        
        convToGroupMap.put(conversation, group);
        
        if (TraceComponent.isAnyTracingEnabled() && tc.isEntryEnabled()) SibTr.exit(tc, "create", group);
        return group;
     }
docs: Creates a proxy queue conversation group.
  @see com.ibm.ws.sib.comms.client.proxyqueue.ProxyQueueConversationGroupFactory#create(com.ibm.ws.sib.jfapchannel.Conversation)