}

    @Test
    @DisplayName("nextCalledName should return valid name for fallback attempts")
    void testNextCalledNameContract() {
        // Given
        String expectedNextName = "SERVER15";
        when(mockAddress.nextCalledName(mockContext)).thenReturn(expectedNextName);

        // When
        String nextName = mockAddress.nextCalledName(mockContext);

        // Then

        // Arrange
        NbtAddress nbtMock = mock(NbtAddress.class);
        when(nbtMock.nextCalledName()).thenReturn("NEXT");
        UniAddress ua = new UniAddress(nbtMock);
        // Act
        String next = ua.nextCalledName();
        // Assert
        assertEquals("NEXT", next, "nextCalledName should delegate to NbtAddress when called");
    }

    @Test

        // Test nextCalledName when calledName is hostName.name initially
        mockName = new Name(mockConfig, "MYSERVER", 0x20, null);
        NbtAddress nbtAddress = new NbtAddress(mockName, testAddressInt, false, NbtAddress.H_NODE);
        nbtAddress.firstCalledName(); // Initialize calledName
        assertEquals(NbtAddress.SMBSERVER_NAME, nbtAddress.nextCalledName(mockContext));
    }

    @Test

            UniAddress uniAddress = new UniAddress(mockNbtAddress);
            when(mockNbtAddress.nextCalledName(mockCIFSContext)).thenReturn("NEXT_NBT_NAME");
            assertEquals("NEXT_NBT_NAME", uniAddress.nextCalledName(mockCIFSContext));
            verify(mockNbtAddress, times(1)).nextCalledName(mockCIFSContext);
        }

        @Test

     * @param tc
     *            context to use
     *
     * @return guessed alternate name
     */
    @Override
    public String nextCalledName(final CIFSContext tc) {
        if (this.addr instanceof NbtAddress) {
            return ((NbtAddress) this.addr).nextCalledName(tc);
        }
        if (this.calledName != NbtAddress.SMBSERVER_NAME) {
            this.calledName = NbtAddress.SMBSERVER_NAME;

     * methods are used by the smb package.
     *
     * @param tc the transport context to use for name resolution
     *
     * @return guessed name
     */
    String nextCalledName(CIFSContext tc);

     * method is used exclusively by the <code>jcifs.smb1.smb1</code> package.
     *
     * @return the next called name to try
     */

    public String nextCalledName() {
        if (addr instanceof NbtAddress) {
            return ((NbtAddress) addr).nextCalledName();
        }
        if (calledName != NbtAddress.SMBSERVER_NAME) {
            calledName = NbtAddress.SMBSERVER_NAME;
            return calledName;
        }

        return this.calledName;
    }

    /**
     *
     * @param tc
     *            context to use
     * @return net name to try
     */
    @Override
    public String nextCalledName(final CIFSContext tc) {

        if (this.calledName == this.hostName.name) {
            this.calledName = SMBSERVER_NAME;
        } else if (SMBSERVER_NAME.equals(this.calledName)) {

            default:
                disconnect(true);
                throw new NbtException(NbtException.ERR_SSN_SRVC, 0);
            }
        } while ((calledName.name = address.nextCalledName()) != null);

        throw new IOException("Failed to establish session with " + address);
    }

    private void negotiate(int port, final ServerMessageBlock resp) throws IOException {

    }

    /**
     * Gets the next called name for session establishment.
     *
     * @return the next called name to try, or null if no more names available
     */
    public String nextCalledName() {

        if (calledName == hostName.name) {
            calledName = SMBSERVER_NAME;
        } else if (calledName == SMBSERVER_NAME) {
            NbtAddress[] addrs;

            try {