Smak 4.4.6: ConnectionListener#connected() returned XMPPConnection value may contain NULL

[cmeng]

Below is an extraction of the Google Play Console, Crashes and ANRs Stack trace reported for aTalk v3.1.4 release based on smack 4.4.6.

Stack trace

Sample attributes:
HUAWEI HWELE (HUAWEI P30)
a. Android 10 (SDK 29)
b. Version: 301040 (3.1.4) Occurred: 11 days ago

Type: java.lang.IllegalArgumentException

Exception java.lang.IllegalArgumentException: XMPPConnection must not be null
  at org.jivesoftware.smack.util.Objects.requireNonNull (Objects.java:42)
  at org.jivesoftware.smack.Manager.<init> (Manager.java:33)
  at org.jivesoftware.smackx.iqversion.VersionManager.<init> (VersionManager.java:84)
  at org.jivesoftware.smackx.iqversion.VersionManager.getInstanceFor (VersionManager.java:106)
  at net.java.sip.communicator.impl.protocol.jabber.ProtocolProviderServiceJabberImpl.initServicesAndFeatures (ProtocolProviderServiceJabberImpl.java:1823)
  at net.java.sip.communicator.impl.protocol.jabber.ProtocolProviderServiceJabberImpl.access$1100 (ProtocolProviderServiceJabberImpl.java:271)
  at net.java.sip.communicator.impl.protocol.jabber.ProtocolProviderServiceJabberImpl$XMPPConnectionListener.connected (ProtocolProviderServiceJabberImpl.java:1464)
  at org.jivesoftware.smack.AbstractXMPPConnection.callConnectionConnectedListener (AbstractXMPPConnection.java:1696)
  at org.jivesoftware.smack.AbstractXMPPConnection.connect (AbstractXMPPConnection.java:542)
  at org.jivesoftware.smack.ReconnectionManager$2.run (ReconnectionManager.java:282)
  at java.lang.Thread.run (Thread.java:929)
  at java.lang.Thread.run (Thread.java:784)	

aTalk implements smack ConnectionListener interface, and below is only called in ConnectionListener callback connected(XMPPConnection connection).

initServicesAndFeatures();

Any reason why “XMPPConnection connection” is null even when the service is connected?

private class XMPPConnectionListener implements ConnectionListener {
  .....
        /**
         * Notification that the connection has been successfully connected to the remote endpoint (e.g. the XMPP server).
         *
         * Note that the connection is likely not yet authenticated and therefore only limited operations
         * like registering an account may be possible.
         *
         * @param connection the XMPPConnection which successfully connected to its endpoint.
         */
        public void connected(XMPPConnection connection) {
            /*
             * re-init mConnection in case this is a new re-connection; FFR:
             * java.lang.IllegalArgumentException:
             * at org.jivesoftware.smack.util.Objects.requireNonNull (Objects.java:42)
             *  at org.jivesoftware.smack.Manager.<init> (Manager.java:33)
             *  at org.jivesoftware.smackx.iqversion.VersionManager.<init> (VersionManager.java:84)
             *  at org.jivesoftware.smackx.iqversion.VersionManager.getInstanceFor (VersionManager.java:106)
             *  at net.java.sip.communicator.impl.protocol.jabber.ProtocolProviderServiceJabberImpl.initServicesAndFeatures (ProtocolProviderServiceJabberImpl.java:1734)
             */
            mConnection = (AbstractXMPPConnection) connection;

            xmppConnected.reportSuccess();
            if (connection instanceof XMPPTCPConnection)
                setTrafficClass();

            // check and set auto tune ping interval if necessary
            tunePingInterval();

            // must initialize caps entities upon success connection to ensure it is ready for the very first <iq/> send
            initServicesAndFeatures();

            /*  Start up External Service Discovery Manager XEP-0215 */
            ExternalServiceDiscoveryManager.getInstanceFor(connection);

            /*
             * Broadcast to all others after connection is connected but before actual account registration start.
             * This is required by others to init their states and get ready when the user is authenticated
             */
            // fireRegistrationStateChanged(RegistrationState.UNREGISTERED, RegistrationState.REGISTERING,
            //        RegistrationStateChangeEvent.REASON_USER_REQUEST, "TCP Connection Successful");
        }
....
}