private static void setLogLevel(String level) {
		Level logLevel = Level.INFO;
		Level oldlevel = LOG.getLogger(PACKAGE_ROOT).getLevel();
		switch (loglevels.valueOf(level)) {
			case all : logLevel = Level.ALL;break;
			case info : logLevel = Level.INFO;break;
			case warn : logLevel = Level.WARN;break;
			case debug : logLevel = Level.DEBUG;break;
			case trace : logLevel = Level.TRACE;break;
			case error: logLevel = Level.ERROR;break;
			case fatal: logLevel = Level.FATAL;break;
			case off: logLevel = Level.OFF;break;
		}
		if (logLevel.toInt()!=oldlevel.toInt()) {
			LOG.getLogger(PACKAGE_ROOT).setLevel(logLevel);
			LOG.info("logging level: " + logLevel);
		}
	}