public class ISGIPoEProtocolHandler extends ISGProtocolHandler implements RadiusProtocolHandler {
    ...
    private class DeviceNasPortMap implements EventListener<DeviceInterfaceModifiedEvent> {

        public DeviceNasPortMap(int moduleId, int deviceId, SortedMap<Integer, ParameterMap> patternMap) throws BGException {
            ...
            EventProcessor.getInstance().addListener(this, DeviceInterfaceModifiedEvent.class);
            ...
        }
    ...
    }
}