@DisplayName("toString() renders lower-case hex with zero-padding")
    void toString_rendersHex(byte[] input, String expected) {
        // Arrange
        SecurityBlob blob = new SecurityBlob(input);

        // Act
        String actual = blob.toString();

        // Assert
        assertEquals(expected, actual, "Hex string should match expected format");
    }

    @Test
    void constructorAcceptsNonNullObject() {
        // Arrange : create a dummy address
        InetAddress dummy = mock(InetAddress.class);
        // Act
        UniAddress ua = new UniAddress(dummy);
        // Assert
        assertSame(dummy, ua.getAddress(), "constructor should store the supplied address");
    }

    @Test
    void constructorRejectsNull() {

class SmbEndOfFileExceptionTest {

    /**
     * Verifies the no-arg constructor sets the expected message, status, and no cause.
     */
    @Test
    void defaultConstructorSetsMessageAndStatus() {
        // Arrange & Act
        SmbEndOfFileException ex = new SmbEndOfFileException();

        // Assert
        assertEquals("Unexpectedly reached end of file", ex.getMessage(), "Default message must match");

        assertEquals(0, transport.getNumSessions());

        // Act: create new session (happy path)
        SmbSessionImpl s1 = transport.getSmbSession(ctx);
        assertNotNull(s1);
        assertEquals(1, transport.getNumSessions());
        s1.close();

        // Act: request again with same context -> reuse existing
        SmbSessionImpl s2 = transport.getSmbSession(ctx);

    @Test
    void returnsProvidedValues_happyPath() {
        // Arrange
        SmbBasicFileInfo info = new TestInfo(0x20 /* ARCHIVE */, 1_600_000_000_000L, 1_700_000_000_000L, 1_650_000_000_000L, 42L);

        // Act & Assert
        Assertions.assertEquals(0x20, info.getAttributes(), "attributes should match");
        Assertions.assertEquals(1_600_000_000_000L, info.getCreateTime(), "create time should match");

        URL url = new URL(null, "smb://host/share", handler);

        // Act
        URLConnection conn = handler.openConnection(url);

        // Assert
        assertNotNull(conn);
        assertTrue(conn instanceof SmbFile);
    }

    @Test
    @DisplayName("openConnection throws NPE for null URL")
    void testOpenConnectionWithNullUrl() {
        // Act & Assert

        void doShareEnum_invalidPath_throws(String url, String pathSuffix, boolean expectDirSlashMsg) throws Exception {
            // Arrange
            SmbFile parent = new SmbFile(url);

            // Act + Assert
            SmbException ex = assertThrows(SmbException.class, () -> SmbEnumerationUtil.doShareEnum(parent, "*", 0, null, null));

            // Assert message indicates which validation failed

    @Test
    @DisplayName("byte[] ctor: empty token throws PACDecodingException with clear message")
    void byteArrayConstructor_emptyToken_throws() {
        // Arrange
        byte[] empty = new byte[0];

        // Act + Assert
        PACDecodingException ex = assertThrows(PACDecodingException.class, () -> new KerberosApRequest(empty, new KerberosKey[0]));
        assertTrue(ex.getMessage().contains("Empty kerberos ApReq"));
    }

    @Test

    @Test
    @DisplayName("Default ctor: null message/cause and success status")
    void defaultConstructor_hasNullMessageAndCause_andDefaultStatus() {
        // Arrange & Act
        SMBSignatureValidationException ex = new SMBSignatureValidationException();

        // Assert
        assertNull(ex.getMessage(), "Default ctor should not set a message");

        sqlException.setNextException(sqlException2);
        sqlException2.setNextException(sqlException3);

        final SQLRuntimeException sqlRuntimeException = new SQLRuntimeException(sqlException);

        // ## Act ##
        final String message = sqlRuntimeException.getMessage();

        // ## Assert ##
        System.out.println(message);
        assertContains(message, "ErrorCode=7650");