public String getNormalizedName() {
        String name = getName();
        /*
         * getName() may return a name with a suffix 'rtl' or 'ltr'. This cannot
         * be used to open a charset (e.g. IBM424_rtl). The ending '_rtl' or '_ltr'
         * should be stripped off before creating the string.
         */
        int startSuffix =
                !name.contains("_rtl") ? name.indexOf("_ltr") : name.indexOf("_rtl");
        if (startSuffix > 0) {
            name = name.substring(0, startSuffix);
        }
        return name;
    }
strips e.g. _rtl, _ltr off of charset names so that they can be used as a charset.

@return
tika-parsers/tika-parsers-standard/tika-parsers-standard-modules/tika-parser-text-module/src/main/java/org/apache/tika/parser/txt/CharsetMatch.java