public static void addIfFeatureEnabled(IoFilterChain filterChain, String filterName, long inactivityTimeoutIn, IoSessionEx wsSession, Logger logger) { long inactivityTimeout = getInactivityTimeoutMillis(inactivityTimeoutIn, logger); if (inactivityTimeout > 0) { filterChain.addLast(filterName, new WsCheckAliveFilter(inactivityTimeout, wsSession, logger)); if (logger.isDebugEnabled()) { logger.debug(String.format("Configured WebSocket inactivity timeout (ws.inactivity.timeout) is %d milliseconds", inactivityTimeout)); } } }