关于FloodlightContext的不明白之处

public interface IOFMessageListener extends IListener<OFType>{
openflow消息监听器。
public Command receive(IOFSwitch sw, OFMessage msg, FloodlightContext cntx);
Floodlight用来调用openflow消息监听器的方法。（Floodlight会自己调用该方法吗， cntx到底是怎么传进去的）
@param sw:发送此openflow消息的交换机。
@param msg:消息。
@param cntx:一个Floodlight上下文对象，用于在监听器之间传递消息(如何传递消息?)。

@return:  继续或停止执行的命令。

}

定义 PACKET_IN 消息才处理机制，在最后返回 Command.CONTINUE 将允许这
套消息继续被其他的 PACKET_IN handler 处理。

@Override
public net.floodlightcontroller.core.Ilisterner.Command receive(IOFSwitch sw,
OFMessage msg, FloodlightContext cntx) {
Ethernet eth =
IFloodlightProviderService.bcStore.get(cntx,          /*cntx ：a Floodlight message context object you can use to pass
   * information between listeners
IOFmessageListner中的*/
IFloodlightProviderService.CONTEXT_PI_PAYLOAD);
Long sourceMACHash = Ethernet.toLong(eth.getSourceMACAddress());
if (!macAddresses.contains(sourceMACHash)) {

macAddresses.add(sourceMACHash);
logger.info("MAC Address: {} seen on switch: {}",
HexString.toHexString(sourceMACHash),
sw.getId());
}

return Command.CONTINUE;
}

IFloodlightModule中的类似疑问？

void init(FloodlightModuleContext context) throws FloodlightModuleException;//context怎么传的？
    
    /**
     * This is a hook for each module to do its <em>external</em> initializations,
     * e.g., register for callbacks or query for state in other modules
     *
     * It is expected that this function will not block and that modules that want
     * non-event driven CPU will spawn their own threads.
     *
     * @param context
     */
    
    void startUp(FloodlightModuleContext context);