private static void log(String s, int errorLevel) {
		// only log when error level is sufficient
		if (errorLevel >= logLevel) {
			System.out.print(DateFormat.getInstance().format(new Date().getTime()) + " ");
			System.out.print((errorLevel == INFO ? "INFO" : (errorLevel == DEBUG ? "DEBUG" : "ERROR")) + ": ");
			System.out.print(s);
			System.out.println();
		}
	}