public static void main()

in kerby-kerb/kerb-admin/src/main/java/org/apache/kerby/kerberos/kerb/admin/RemoteAdminClientTool.java [85:170]
68 lines of code
13 McCabe index (conditional complexity)

    public static void main(String[] args) throws Exception {
        AdminClient adminClient;

        if (args.length < 1) {
            System.err.println(USAGE);
            System.exit(1);
        }

        String confDirPath = args[0];

        File confFile = new File(confDirPath, "adminClient.conf");

        final AdminConfig adminConfig = new AdminConfig();
        adminConfig.addKrb5Config(confFile);

        KdcConfig tmpKdcConfig = KdcUtil.getKdcConfig(new File(confDirPath));
        if (tmpKdcConfig == null) {
            tmpKdcConfig = new KdcConfig();
        }

        try {
            Krb5Conf krb5Conf = new Krb5Conf(new File(confDirPath), tmpKdcConfig);
            krb5Conf.initKrb5conf();
        } catch (IOException e) {
            throw new KrbException("Failed to make krb5.conf", e);
        }

        adminClient = new AdminClient(adminConfig);

        File keytabFile = new File(adminConfig.getKeyTabFile());
        if (!keytabFile.exists()) {
            System.err.println("Need the valid keytab file value in conf file.");
            return;
        }

        String adminRealm = adminConfig.getAdminRealm();

        adminClient.setAdminRealm(adminRealm);
        adminClient.setAllowTcp(true);
        adminClient.setAllowUdp(false);
        adminClient.setAdminTcpPort(adminConfig.getAdminPort());

        adminClient.init();
        System.out.println("admin init successful");

        String adminPrincipal = KrbUtil.makeKadminPrincipal(
            adminClient.getSetting().getKdcRealm()).getName();
        Subject subject = null;
        try {
            subject = AuthUtil.loginUsingKeytab(adminPrincipal,
                new File(adminConfig.getKeyTabFile()));
        } catch (LoginException e) {
            LOG.error("Fail to login using keytab. " + e);
            return;
        }

        // set login subject, used by SASL negotiation
        adminClient.setSubject(subject);

        System.out.println("enter \"command\" to see legal commands.");

        Completer completer = new StringsCompleter("add_principal", "delete_principal", "rename_principal",
                "list_principals", "ktadd", "change_password", "get_principal");

        Terminal terminal = null;
        try {
            terminal = TerminalBuilder.terminal();
        } catch (IOException e) {
            e.printStackTrace();
        }
        LineReader lineReader = LineReaderBuilder.builder().completer(completer).terminal(terminal).build();

        while (true) {
            try {
                String line = lineReader.readLine(PROMPT + ": ");
                if ("quit".equals(line) || "exit".equals(line) || "q".equals(line)) {
                    break;
                }
                execute(adminClient, line);
            } catch (UserInterruptException | EndOfFileException ex) {
                break;
            } catch (KrbException e) {
                System.err.println(e.getMessage());
            }
        }
    }