@Override
    public TransportType transportType() {
        if (TransportType.EPOLL.isAvailable()) {
            return TransportType.EPOLL;
        }
        if (TransportType.KQUEUE.isAvailable()) {
            return TransportType.KQUEUE;
        }
        return TransportType.NIO;
    }
Implementation of {@link FlagsProvider} which provides default values to {@link Flags}.
core/src/main/java/com/linecorp/armeria/common/DefaultFlagsProvider.java