* XIncludeの有効／無効を設定します。
     *
     * @param spf
     *            {@link SAXParserFactory}。{@literal null}であってはいけません
     * @param state
     *            XIncludeを有効にするなら<code>true</code>
     * @return XIncludeの有効／無効を設定できた場合は<code>true</code>
     */
    public static boolean setXIncludeAware(final SAXParserFactory spf, final boolean state) {
        assertArgumentNotNull("spf", spf);

        try {

     * @throws Exception
     */
    public void testSetXIncludeAware() throws Exception {
        final SAXParserFactory spf = SAXParserFactoryUtil.newInstance();
        SAXParserFactoryUtil.setXIncludeAware(spf, true);
        spf.setNamespaceAware(true);
        final SAXParser parser = SAXParserFactoryUtil.newSAXParser(spf);

        final InputSource is = new InputSource(ResourceUtil.getResourceAsStream("org/codelibs/core/xml/include.xml"));

        }
    }

    public static SAXParserFactory newSAXParserFactory() {
        try {
            SAXParserFactory spf = SAXParserFactory.newInstance();
            spf.setFeature(XMLConstants.FEATURE_SECURE_PROCESSING, true);
            return spf;
        } catch (ParserConfigurationException e) {
            throw new RuntimeException(errorMessageFor("SAXParserFactory"), e);