UnsupportedOperationException ex = assertThrows(UnsupportedOperationException.class, it::remove);
        assertEquals("remove", ex.getMessage());
    }

    @Nested
    @DisplayName("Invalid constructor inputs")
    class InvalidInputs {
        @Test
        @DisplayName("Null delegate causes NullPointerException during construction")
        void nullDelegate_throwsNPE() throws Exception {

        // Zeroed upon release
        for (byte value : fromCache) {
            assertEquals(0, value);
        }
    }

    // Invalid inputs: negative sizes for constructor arguments
    @Nested
    class InvalidConstruction {
        @Test
        @DisplayName("Negative maxBuffers throws immediately in constructor")
        void negativeMaxBuffersThrows() {

        // Default constructor
    }

    private static int id = 0;
    private static final Logger log = LoggerFactory.getLogger(Transport.class);

    /**
     * Read bytes from the input stream into a buffer
     *
     * @param in the input stream to read from
     * @param b the buffer to read into
     * @param off the offset in the buffer to start writing
     * @param len the number of bytes to read

        validate(form, messages -> {}, () -> asListHtml(form.dictId));
        stemmerOverrideService.getStemmerOverrideItem(form.dictId, form.id).ifPresent(entity -> {
            form.input = entity.getInput();
            form.output = entity.getOutput();
        }).orElse(() -> {
            throwValidationError(messages -> messages.addErrorsCrudCouldNotFindCrudTable(GLOBAL, form.getDisplayId()),

     * This method filters the input URL list to return only those URLs that the specified user
     * has marked as favorites.
     *
     * @param userCode the unique code identifying the user
     * @param urlList the list of URLs to check against the user's favorites

    return RESULT_DATA;
  }

  private class ChainingFunction implements AsyncFunction<Integer, String> {
    @Override
    public ListenableFuture<String> apply(Integer input) throws Exception {
      switch (input) {
        case VALID_INPUT_DATA:
          outputFuture.set(RESULT_DATA);
          break;
        case SLOW_OUTPUT_VALID_INPUT_DATA:
          break; // do nothing to the result

    return RESULT_DATA;
  }

  private class ChainingFunction implements AsyncFunction<Integer, String> {
    @Override
    public ListenableFuture<String> apply(Integer input) throws Exception {
      switch (input) {
        case VALID_INPUT_DATA:
          outputFuture.set(RESULT_DATA);
          break;
        case SLOW_OUTPUT_VALID_INPUT_DATA:
          break; // do nothing to the result

    @MethodSource("hexCases")
    @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");
    }

        @ValueSource(strings = { "192.168.1", "hostname", "1.2.3.4.5", "192.168.1.1a", "a.b.c.d" })
        void shouldReturnFalseForInvalidIpAddressesOrHostnames(String input) {
            assertFalse(UniAddress.isDotQuadIP(input));
        }

        @Test
        void shouldReturnTrueForInvalidOctetValues() {
            // isDotQuadIP does not validate octet values, only checks format

            final VaErrorHook hook) {
        return getEntity(form).map(entity -> {
            final String newInput = form.input;
            validateProtwordsString(action, newInput, "input", hook);
            entity.setNewInput(newInput);
            return entity;
        });
    }