@Nonnull
    @Override
    public Connection getConnection() {
        final Connection connection = super.getConnection();
        assert connection != null; // Openfire does not implement stream management for multiplex connections. Therefor, the connection cannot be null.
        return connection;
    }
Returns the connection associated with this Session.

@return The connection for this session
xmppserver/src/main/java/org/jivesoftware/openfire/session/LocalConnectionMultiplexerSession.java