public static void clearHandlers () {
        Enumeration<String> names = LogManager.getLogManager().getLoggerNames();
        while (names.hasMoreElements()) {
            String name = names.nextElement();
            Logger logger = Logger.getLogger(name);

            Handler[] handlers = logger.getHandlers();
            for (Handler handler : handlers) {
                logger.removeHandler(handler);
            }
        }
    }
Clear all handlers registered in java.util.logging framework
vespalog/src/main/java/com/yahoo/log/LogSetup.java