private void doSaslHandshake()

in kerby-kerb/kerb-admin/src/main/java/org/apache/kerby/kerberos/kerb/admin/kadmin/remote/RemoteKadminImpl.java [276:324]
47 lines of code
9 McCabe index (conditional complexity)

    private void doSaslHandshake() throws Exception {
        Subject.doAs(subject, (PrivilegedExceptionAction<Object>) () -> {
            boolean success = false;
            try {
                Map<String, String> saslProps = new HashMap<>();
                saslProps.put(Sasl.QOP, "auth-conf");
                saslProps.put(Sasl.SERVER_AUTH, "true");
                try {
                    String protocol = innerClient.getSetting().getAdminConfig().getProtocol();
                    String serverName = innerClient.getSetting().getAdminConfig().getServerName();
                    saslClient = Sasl.createSaslClient(new String[]{MECHANISM}, null,
                            protocol, serverName, saslProps, null);
                    this.saslClientWrapper = SaslWrapper.create(saslClient);
                } catch (SaslException e) {
                    throw new KrbException("Fail to create SASL client. " + e);
                }
                if (saslClient == null) {
                    throw new KrbException("Unable to find client implementation for: GSSAPI");
                }
                byte[] response;
                try {
                    response = saslClient.hasInitialResponse()
                            ? saslClient.evaluateChallenge(EMPTY_BYTES) : EMPTY_BYTES;
                } catch (SaslException e) {
                    throw new KrbException("Sasl client evaluate challenge failed." + e);
                }
                sendSaslMessage(response);
                ByteBuffer message = transport.receiveMessage();

                while (!saslClient.isComplete()) {
                    int ssComplete = message.getInt();
                    if (ssComplete == NegotiationStatus.SUCCESS.getValue()) {
                        LOG.info("Sasl Server completed");
                    }
                    sendSaslMessage(SaslUtils.evaluateChallenge(saslClient, message));
                    if (!saslClient.isComplete()) {
                        message = transport.receiveMessage();
                    }

                }
                success = true;
            } finally {
                if (!success) {
                    transport.release();
                }
            }
            return null;
        });
    }