protected int executeCommand(final String[] commands, final String username, final String password) {
        if (commands == null || commands.length == 0) {
            throw new CommandExecutionException("command is empty.");
        }

        if (logger.isInfoEnabled()) {
            logger.info("Command: {}", String.join(" ", commands));
        }

        final String[] cmds = stream(commands).get(stream -> stream.map(s -> {