* strip invalid XML characters, and parse XML content into a map of data.
 *
 * <p>
 * The class is final and cannot be instantiated.
 * </p>
 *
 * <h2>Methods:</h2>
 * <ul>
 *   <li>{@link #escapeXml(String)}: Escapes special characters in an XML string.</li>
 *   <li>{@link #stripInvalidXMLCharacters(String)}: Strips invalid XML characters from a string.</li>

        if (m.matches() && m.groupCount() > 0) {
            return m.group(1);
        }
        return null;
    }

    /**
     * Strips comments from a line (everything after '#' character).
     * @param line the line to strip comments from
     * @return the line without comments
     */
    protected String stripComment(final String line) {
        final int commentIndex = line.indexOf('#');