return false;
  }

  @Override
  public T get() {
    throw new IllegalStateException("Optional.get() cannot be called on an absent value");
  }

  @Override
  public T or(T defaultValue) {
    return checkNotNull(defaultValue, "use Optional.orNull() instead of Optional.or(null)");
  }

  @SuppressWarnings("unchecked") // safe covariant cast
  @Override
  public Optional<T> or(Optional<? extends T> secondChoice) {

        FessProp.propMap.clear();
        FessConfig fessConfig = new FessConfig.SimpleImpl() {
            @Override
            public String getSystemProperty(final String key, final String defaultValue) {
                return systemPropMap.getOrDefault(key, defaultValue);
            }

            @Override
            public boolean isCrawlerIgnoreRobotsTxt() {
                return false;
            }

            @Override

    private String getDefaultMessage() {
        try {
            final Method method = UriType.class.getMethod("message");
            final Object defaultValue = method.getDefaultValue();
            return defaultValue != null ? defaultValue.toString() : null;
        } catch (final Exception e) {
            return "{org.lastaflute.validator.constraints.UriType.message}";
        }
    }

     * @param clazz the class type to convert the value to
     * @param defaultValue the default value to return if the key is not found or conversion fails
     * @return the converted value or the default value if not found
     */
    public static <T> T getValue(final Map<String, Object> doc, final String key, final Class<T> clazz, final T defaultValue) {
        final T value = getValue(doc, key, clazz);
        if (value == null) {

        @ValueSource(strings = { "text/unknown", "application/x-unknown", "custom/type", "" })
        void testVariousDefaultValues(String defaultValue) throws IOException {
            assertEquals(defaultValue, mimeMap.getMimeType("notinmap", defaultValue));
        }
    }

    @Nested
    @DisplayName("Edge cases and special scenarios")
    class EdgeCases {

        @Test

                String defaultValue = ce.getAttribute("default-value", null);
                if (value != null || defaultValue != null) {
                    XmlNode e = XmlNode.newInstance(
                            ce.getName(),
                            value,
                            defaultValue != null ? Collections.singletonMap("default-value", defaultValue) : null,
                            null,

     * @param key The key of the parameter.
     * @param defaultValue The default value if the parameter is not found.
     * @param clazz The class type to convert the parameter to.
     * @return The parameter value, or the default value if not found.
     */
    protected <T> T getInitParameter(final String key, final T defaultValue, final Class<T> clazz) {
        if (initParamMap != null) {
            try {

  }

  @Override
  public boolean isPresent() {
    return true;
  }

  @Override
  public T get() {
    return reference;
  }

  @Override
  public T or(T defaultValue) {
    checkNotNull(defaultValue, "use Optional.orNull() instead of Optional.or(null)");
    return reference;
  }

  @Override
  public Optional<T> or(Optional<? extends T> secondChoice) {
    checkNotNull(secondChoice);

    }

    @Override
    public File getFile() {
        return artifact.getFile();
    }

    @Override
    public String getProperty(String key, String defaultValue) {
        return artifact.getProperty(key, defaultValue);
    }

    @Override
    public Map<String, String> getProperties() {
        return artifact.getProperties();
    }

    public String getMessage() {

          <version>1.0.0+</version>
          <description>Whether to use a local copy instead (with filename that includes the base version)</description>
          <type>boolean</type>
          <defaultValue>false</defaultValue>
        </field>
      </fields>
    </class>
    <class java.clone="deep">
      <name>SnapshotVersion</name>
      <version>1.1.0+</version>