@Override
    public void close(PingSession pingSession) {
        Objects.requireNonNull(pingSession, "pingSession");

        pingSessionRegistry.remove(pingSession);

        if (logger.isDebugEnabled()) {
            logger.debug("Remove ping session. pingSession={}", pingSession);
        }
        lifecycleListener.close(pingSession);
    }
@author Woonduk Kang(emeroad)
@author jaehong.kim
collector/src/main/java/com/navercorp/pinpoint/collector/grpc/lifecycle/DefaultPingEventHandler.java