}

    public void test_stripInvalidXMLCharacters_null() {
        // Test null input
        assertNull(XmlUtil.stripInvalidXMLCharacters(null));
    }

    public void test_stripInvalidXMLCharacters_empty() {
        // Test empty string
        assertEquals("", XmlUtil.stripInvalidXMLCharacters(""));
    }

    public void test_stripInvalidXMLCharacters_valid() {
        // Test valid XML characters

 *
 * <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>
 *   <li>{@link #getDataMap(AccessResultData)}: Parses XML content from {@link AccessResultData} and returns a map of the data.</li>
 * </ul>
 *