} else if (args[i].equals("-u")) {
i++;
if (i >= args.length) {
throw new IllegalArgumentException("user_list is missing");
}
users.fill(args[i]);
} else if (args[i].equals("-f")) {
force = true;
} else if (args[i].charAt(0) == '-') {
out.println(getUsage());
out.flush();