public static boolean hasAlertLevel(final Level level) {
    if (level == Level.FATAL) {
      return true;
    } else if (level == Level.ERROR) {
      return true;
    } else if (level == Level.WARN) {
      return true;
    } else {
      return level == Level.OFF;
    }
  }
True if the Log4J2 {@code Level} converts to an {@link AlertLevel}.
geode-core/src/main/java/org/apache/geode/alerting/internal/log4j/AlertLevelConverter.java