@SuppressWarnings("unchecked")
    protected void handleError( Throwable t )
    {
        // If there are no listeners then close the connection with
        // a reason
        if( errorListeners.isEmpty() ) {
            log.log( Level.SEVERE, "Terminating connection due to unhandled error", t );
            DisconnectInfo info = new DisconnectInfo();
            info.reason = "Connection Error";
            info.error = t;
            closeConnections(info);
            return;
        }
    
        for( ErrorListener l : errorListeners ) {
            l.handleError( this, t );
        } 
    }
Either calls the ErrorListener or closes the connection
 if there are no listeners.
jme3-networking/src/main/java/com/jme3/network/base/DefaultClient.java