public void changeLogLevel(final String logLevel, String logFile) throws CommandLineParsingException { Objects.requireNonNull(logLevel, "logLevel must not be null"); try { Logger log = LogFactory.getInstance().getLog(); if (logFile != null && logFile.length() > 0) { log.setLogLevel(logLevel, logFile); } else { log.setLogLevel(logLevel); } } catch (IllegalArgumentException ex) { throw new CommandLineParsingException(ex.getMessage(), ex); } }