The first two callback methods, subscribed(int, byte[]) and unsubscribed(int), are for clients that want to monitor subscription acknowledgments.

前两个回调方法：subscribed(int, byte[]) 和 unsubscribed(int) 主要针对想要监视订阅确认的客户机。

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By means of byte code rewritten, the mechanism can forcibly unload the given service and can monitor main CPU, memory and networking bandwidth resources without modifying any of original code.

该机制主要利用字节码重写技术，在不修改主动代码的前提下可以实现服务的强制性终止和针对主体的CPU、内存以及网络带宽的资源监控。

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