class LoadBalancer implements IFloodlightModule,
    ILoadBalancerService, IOFMessageListener {

    @Override
    public net.floodlightcontroller.core.IListener.Command
            receive(IOFSwitch sw, OFMessage msg, FloodlightContext cntx) {
        switch (msg.getType()) {
            case PACKET_IN:
                return processPacketIn(sw, (OFPacketIn)msg, cntx);
            default:
                break;
        }
        log.warn("Received unexpected message {}", msg);
        return Command.CONTINUE;
    }

}