Intermittent ConnectThread Exception

[dbzhang]

I intermittently encounter the following fatal exception after I connect to my server. I've attached the crash logs to help identify the issue. Is there something I'm doing incorrect here?

05-21 16:23:10.367: I/System.out(7412): Connection established
05-21 16:23:10.375: W/dalvikvm(7412): threadid=17: thread exiting with uncaught exception (group=0x4001e560)
05-21 16:23:10.375: E/AndroidRuntime(7412): FATAL EXCEPTION: ConnectThread
05-21 16:23:10.375: E/AndroidRuntime(7412): java.lang.IllegalStateException: TimerTask is canceled
05-21 16:23:10.375: E/AndroidRuntime(7412): at java.util.Timer.scheduleImpl(Timer.java:578)
05-21 16:23:10.375: E/AndroidRuntime(7412): at java.util.Timer.schedule(Timer.java:461)
05-21 16:23:10.375: E/AndroidRuntime(7412): at io.socket.IOConnection.resetTimeout(IOConnection.java:480)
05-21 16:23:10.375: E/AndroidRuntime(7412): at io.socket.IOConnection.transportConnected(IOConnection.java:515)
05-21 16:23:10.375: E/AndroidRuntime(7412): at io.socket.WebsocketTransport.onOpen(WebsocketTransport.java:123)
05-21 16:23:10.375: E/AndroidRuntime(7412): at de.roderick.weberknecht.WebSocketConnection.connect(WebSocketConnection.java:139)
05-21 16:23:10.375: E/AndroidRuntime(7412): at io.socket.WebsocketTransport.connect(WebsocketTransport.java:129)
05-21 16:23:10.375: E/AndroidRuntime(7412): at io.socket.IOConnection.connectTransport(IOConnection.java:332)
05-21 16:23:10.375: E/AndroidRuntime(7412): at io.socket.IOConnection.access$300(IOConnection.java:38)
05-21 16:23:10.375: E/AndroidRuntime(7412): at io.socket.IOConnection$ConnectThread.run(IOConnection.java:201)

[dbzhang]

Additionally, I intermittently run into the following fatal exception when I force a disconnect and quickly connect the socket again. I've tried catching these two exceptions in my function containing .connect(new IOCallback{...}); without any luck. Once again, am I doing something wrong here?

05-21 16:38:06.305: W/dalvikvm(7566): threadid=33: thread exiting with uncaught exception (group=0x4001e560)
05-21 16:38:06.305: E/AndroidRuntime(7566): FATAL EXCEPTION: backgroundTimer
05-21 16:38:06.305: E/AndroidRuntime(7566): java.lang.NullPointerException
05-21 16:38:06.305: E/AndroidRuntime(7566): at io.socket.IOConnection.connectTransport(IOConnection.java:323)
05-21 16:38:06.305: E/AndroidRuntime(7566): at io.socket.IOConnection.access$300(IOConnection.java:38)
05-21 16:38:06.305: E/AndroidRuntime(7566): at io.socket.IOConnection$ReconnectTask.run(IOConnection.java:173)
05-21 16:38:06.305: E/AndroidRuntime(7566): at java.util.Timer$TimerImpl.run(Timer.java:284)

[Gottox]

Can you attach the corresponding output of the server?

About your second post: This could be a bug. Did you create a new instance of SocketIO or reused the old one?
I forgot to document that SocketIO (as well as IOConnections, but they're only used internally) are invalidated once onError() or onDisconnect() is called. Use a fresh instance of SocketIO instead. In any way, the library shouldn't throw an NullpointerException but a RuntimeException when you try to reconnect with an invalidated IOConnection.

[dbzhang]

Thanks for your quick response. Could you elaborate on what kind of server output you'd like?

As for the second post, my app has two states: one which requires a connection to the node server and one which does not. I force hard connects and disconnects to accomplish this, please let me know if there is a better approach.

When the connection is required:
I create a new instance of SocketIO and call .connect() with all my callback implementations each time the client connects. Sample code:
socket = new SocketIO(socketUrl);
socket.connect(new IOCallback() { ..my implementation.. });

When the connection is unnecessary:
I force a disconnect. SampleCode:
socket.disconnect();
socket = null;

[Gottox]

socket.io prints per default some status informations to stderr, they could be usefull.

It's ok to disconnect and reconnect to a server, but disconnecting/reconnecting should be done in the same thread, otherwise the state may be inconsistent.

What causes the reconnect error is the mutliton pattern in socket.io-java-client. When a SocketIO client connects to the server, it first looks up if there already is a established IOConnection to the server. If so, it is reused. In that way socket.io needs only one tcp-socket for any example.com/* address. My suspiction is, that the new SocketIO instance finds an IOConnection, which state is currently disconnecting.

May you recheck your issues with current master branch? - Please report if the behavior has changed. especially for your second issue.

[dbzhang]

Just saw your new changes. I'll update my library and keep you posted on the status for the 2nd issue. Thanks a lot