ComponentUtil.setFessConfig(new FessConfig.SimpleImpl() {
            private static final long serialVersionUID = 1L;

            @Override
            public String getCrawlerDocumentMimetypeExtensionOverrides() {
                return "";
            }
        });

        mimeTypeHelper.init();

        // With empty config, no override is applied; content-based detection runs

     * where each line contains a mapping in the format ".ext=mime/type".
     */
    @PostConstruct
    public void init() {
        final String overrides = ComponentUtil.getFessConfig().getCrawlerDocumentMimetypeExtensionOverrides();
        if (StringUtil.isNotBlank(overrides)) {
            final Map<String, String> map = new LinkedHashMap<>();

     * @return The value of found property. (NotNull: if not found, exception but basically no way)
     */
    String getCrawlerDocumentMimetypeExtensionOverrides();

    /**
     * Get the value for the key 'crawler.document.mimetype.extension.overrides' as {@link Integer}. <br>
     * The value is, e.g.  <br>