private final String domain;
        private final boolean anonymous;
        private final boolean guest;
        private final Subject subject;
        private final boolean failOnRefresh;

        TestCredentials(String domain, boolean anonymous, boolean guest, Subject subject, boolean failOnRefresh) {
            this.domain = domain;
            this.anonymous = anonymous;
            this.guest = guest;

        assertTrue(npe2.getMessage().contains("non-null"));
        verifyNoInteractions(mockDir);
    }

    /**
     * Sanity: implementing via an anonymous class works the same as a lambda.
     */
    @Test
    @DisplayName("anonymous class implementation behaves correctly")
    void anonymousClassImplementation() throws Exception {
        SmbFilenameFilter filter = new SmbFilenameFilter() {

    }

    // Test ANONYMOUS constant
    @Test
    void testAnonymousConstant() {
        assertNotNull(NtlmPasswordAuthentication.ANONYMOUS);
        assertEquals("", NtlmPasswordAuthentication.ANONYMOUS.getDomain());
        assertEquals("", NtlmPasswordAuthentication.ANONYMOUS.getUsername());
        assertEquals("", NtlmPasswordAuthentication.ANONYMOUS.getPassword());
    }

    void isAnonymous_behaviour() {
        Kerb5Authenticator anon = new Kerb5Authenticator((Subject) null);
        assertTrue(anon.isAnonymous(), "Null subject with default super should be anonymous");

        Kerb5Authenticator nonAnon = new Kerb5Authenticator(new Subject());
        assertFalse(nonAnon.isAnonymous());
    }

    static Object[][] preferredMechData_nonAnonymous() {

        byte[] token = negoResp.getSecurityBlob();
        final int securityMode = negoResp.getSecurityMode();
        boolean anonymous = this.credentials.isAnonymous();
        final boolean doSigning = securityMode != 0 && !anonymous;
        long newSessId = 0;
        long curSessId = this.sessionId;

        synchronized (trans) {
            this.credentials.refresh();

        bufferIndex += securityBufferLength;

        return bufferIndex - start;
    }

    /**
     * Checks whether the session is either anonymous or a guest session
     *
     * @return whether the session is either anonymous or a guest session
     */
    public boolean isLoggedInAsGuest() {
        return (this.sessionFlags & (SMB2_SESSION_FLAGS_IS_GUEST | SMB2_SESSION_FLAGS_IS_NULL)) != 0;
    }

    /**
     * Get the domain of the user account.
     * @return the domain the user account is in
     */
    String getUserDomain();

    /**
     * Check if these are anonymous credentials.
     * @return whether these are anonymous credentials
     */
    boolean isAnonymous();

    /**
     * Check if these are guest credentials.
     * @return whether these are guest credentials
     */
    boolean isGuest();

 * scattered authentication implementations.
 */
public interface AuthenticationProvider {

    /**
     * Authentication type enumeration
     */
    enum AuthType {
        NTLM, KERBEROS, SPNEGO, GUEST, ANONYMOUS
    }

    /**
     * Gets the authentication type
     *
     * @return the authentication type
     */
    AuthType getAuthType();

    /**
     * Authenticates using the provided context
     *

        try (SmbSessionImpl treesess = t.getSession()) {
            if (treesess.getCredentials().isAnonymous() || treesess.getCredentials().isGuest()) {
                // refresh anonymous session or fallback to anonymous from guest login
                try (SmbSessionInternal s =
                        trans.getSmbSession(this.ctx.withAnonymousCredentials(), treesess.getTargetHost(), treesess.getTargetDomain())

import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;

class MessageTest {

    private Message message;

    @BeforeEach
    void setUp() {
        // Create an anonymous implementation of the Message interface for testing
        message = new Message() {
            private boolean retainPayload = false;
            private byte[] rawPayload;

            @Override