SimUserDataListener.userJoinedChannel() not always called?

I’ve noticed that sometimes on the server, SimUserDataListener.userJoinedChannel() is not called eventhough, on the client, UserManagerClientListener.joinedChannel() is called. If a second client connects, userJoinedChannel() is called correctly. Also if I sleep for a second before opening the channel, SimUserDataListener.userJoinedChannel() is properly called on the server.

Could this be happening because the transaction where SimTask.getCurrent().addUserDataListener() on the server has not finished yet when the client attempts to m_manager.openChannel()? Is this to be expected or am I doing something weird?

Here’s a snippet from my client:

	
public class Main implements ClientConnectionManagerListener, ClientChannelListener
{
...
        public void connected(byte[] values)
	{
		log("connected():"+ StringUtils.bytesToHex(values));
		
		try
		{
			Thread.sleep(1000);
		}
		catch(InterruptedException ignore)
		{
			
		}
		m_manager.openChannel(GAME_CHANNEL);
	}

...

}


And here’s a snippet from my server class:


public class RockPaperScissorsBoot implements SimBoot<RockPaperScissorsBoot>,
		SimUserDataListener, SimUserListener
{
...
	public void boot(com.sun.gi.logic.GLOReference<? extends RockPaperScissorsBoot> gLOReference,
			boolean firstBoot)
	{
		SimTask task = SimTask.getCurrent();
		
		log("RockPaperScissorsBoot.boot(), appid="+task.getAppID());
		m_thisObj = gLOReference;
		m_gameChannel = task.openChannel(GAME_CHANNEL);
		
		task.addUserListener(m_thisObj);
	}
...

	public void userJoined(com.sun.gi.comm.routing.UserID userID, javax.security.auth.Subject subject)
	{
		String loginName;
		Set<Principal> principals = subject.getPrincipals();
		
		// first principal always contains the login name
		Principal principal = principals.iterator().next();
		loginName = principal.getName();
		log("User joined server: "+userID+" login:"+loginName);
		
		m_users.add(userID);
		m_loginNameMap.put(userID, loginName);
		SimTask.getCurrent().addUserDataListener(userID, m_thisObj);
	}

	public void userJoinedChannel(com.sun.gi.comm.routing.ChannelID channelID, com.sun.gi.comm.routing.UserID userID)
	{
		log("userJoinedChannel(): channel="+channelID.toString()+" userID:"+userID.toString());
                ...
        }

...

}

I think this is what is happening:

          Client                                                  Server
                |                                                         |
            connect()------------------------------------> userJoined()
                                                                 transaction started??
                                                                 addUserDataListener() // register channel listener
            connected() <----------------------------     notify client of connection // not clear when this event happens but it seems to be here
            openChannel() --------------------------->  oops, but transaction has not been commited yet(?), so there is no channel listener
                                                                 transaction ends(?), now channel listener has really been registered

Yes its quite possible that thre is a synchronization issue there. There is a known problem (which I believe is fixed next release) where the client gets the “connected” message before the server has finished processing the connection.

In the mean time, see if putting a small sleep in your connected() callback solves the problem.