private static boolean validateTransportType(TransportType transportType, String friendlyName) {
        if (transportType.isAvailable()) {
            logger.info("Using {}", friendlyName);
            return true;
        } else {
            final Throwable cause = transportType.unavailabilityCause();
            if (cause != null) {
                logger.info("{} not available: {}", friendlyName, cause.toString());
            } else {
                logger.info("{} not available: ?", friendlyName);
            }
            return false;
        }
    }
The system properties that affect Armeria's runtime behavior. The priority or each flag is determined
by {@link FlagsProvider#priority()}. On each flag, if value is fail to validated. The next candidate will be
used.
core/src/main/java/com/linecorp/armeria/common/Flags.java