taglibfactory.java

freemaker安装软件

            String nsuri,
            String localName,
            String qName,
            Attributes atts) {
            if ("uri".equals(qName)) {
                buf = new StringBuffer();
            }
        }

        public void characters(char[] chars, int off, int len) {
            if (buf != null) {
                buf.append(chars, off, len);
            }
        }

        public void endElement(String nsuri, String localName, String qName) {
            if ("uri".equals(qName)) {
                uri = buf.toString().trim();
                buf = null;
            }
        }
    }

    private static void parseXml(InputStream in, String url, DefaultHandler handler)
    throws 
        ParserConfigurationException, IOException, SAXException
    {
        InputSource is = new InputSource();
        is.setByteStream(in);
        is.setSystemId(url);
        SAXParserFactory factory = SAXParserFactory.newInstance();
        factory.setNamespaceAware(false);
        factory.setValidating(true);
        XMLReader reader = factory.newSAXParser().getXMLReader();
        reader.setEntityResolver(new LocalTaglibDtds());
        reader.setContentHandler(handler);
        reader.parse(is);
    }

    private static final class Taglib implements TemplateHashModel {
        private Map tags;

        Taglib() {
        }

        public TemplateModel get(String key) {
            return (TagTransformModel) tags.get(key);
        }

        public boolean isEmpty() {
            return false;
        }
        
        boolean load(String uri, ServletContext ctx, Map locations)
        throws 
            ParserConfigurationException, 
            IOException, 
            SAXException,
            TemplateModelException
        {
            String[] tldPath = getTldPath(uri, locations);
            if(logger.isDebugEnabled()) {
                if(tldPath == null) {
                    logger.debug("Loading taglib " + uri + " from location null");
                }
                else {
                    logger.debug("Loading taglib " + uri + " from location " + tldPath[0] + (tldPath[1] != null ? "!" + tldPath[1] : ""));
                }
            }
            tags = loadTaglib(tldPath, ctx);
            if(tags != null) {
                locations.remove(uri);
                return true;
            }
            else {
                return false;
            }
        }
    }

    private static final Map loadTaglib(String[] tldPath, ServletContext ctx)
    throws
        ParserConfigurationException, IOException, SAXException, TemplateModelException
    {
        if (tldPath == null) {
            return null;
        }
        String filePath = tldPath[0]; 
        TldParser tldParser = new TldParser();
        InputStream in = ctx.getResourceAsStream(filePath);
        if(in == null) {
            throw new TemplateModelException("Could not find webapp resource " + filePath);
        }
        String url = ctx.getResource(filePath).toExternalForm();
        try {
            String jarPath = tldPath[1];
            if(jarPath != null) {
                ZipInputStream zin = new ZipInputStream(in);
                for(;;) {
                    ZipEntry ze = zin.getNextEntry();
                    if(ze == null) {
                        throw new TemplateModelException("Could not find JAR entry " + jarPath + " inside webapp resource " + filePath);
                    }
                    String zname = ze.getName(); 
                    if(zname.equals(jarPath)) {
                        parseXml(zin, "jar:" + url + "!" + zname, tldParser);
                        break;
                    }
                }
            }
            else {
                parseXml(in, url, tldParser);
            }
        }
        finally {
            in.close();
        }
        EventForwarding eventForwarding = EventForwarding.getInstance(ctx);
        if(eventForwarding != null) {
            eventForwarding.addListeners(tldParser.getListeners());
        }
        else if(tldParser.getListeners().size() > 0) {
            throw new TemplateModelException(
                "Event listeners specified in the TLD could not be " +
                " registered since the web application doesn't have a" +
                " listener of class " + EventForwarding.class.getName() + 
                ". To remedy this, add this element to web.xml:\n" +
                "| <listener>\n" +
                "|   <listener-class>" + EventForwarding.class.getName() + "</listener-class>\n" +
                "| </listener>");
        }
        return tldParser.getTags();
    }

    private static final String[] getTldPath(String uri, Map locations)
    {
        String[] path = (String[])locations.get(uri);
        // If location was explicitly defined in web.xml, or discovered in a
        // JAR file, use it. (Hopefully this is 99% of the cases)
        if(path != null) {
            return path;
        }
        
        // If there was no explicit mapping in web.xml, but URI is a 
        // ROOT_REL_URI, return it (JSP.7.6.3.2)
        if(uri.startsWith("/")) {
            path = new String[2];
            path[0] = uri;
            if(uri.endsWith(".jar") || uri.endsWith(".zip")) {
                path[1] = "META-INF/taglib.tld";
            }
            return path;
        }

        return null;
    }

    private static String resolveRelativeUri(String uri)
    throws
        TemplateModelException
    {
        // Absolute and root-relative URIs are left as they are.
        if(uri.startsWith("/") || uri.indexOf("://") != -1) {
            return uri;
        }
        
        // Otherwise it is a NOROOT_REL_URI, and has to be resolved relative
        // to current page... We have to obtain the request object to know what
        // is the URL of the current page (this assumes there's a 
        // HttpRequestHashModel under name FreemarkerServlet.KEY_REQUEST in the
        // environment...) (JSP.7.6.3.2)
        TemplateModel reqHash = 
            Environment.getCurrentEnvironment().getVariable(
                FreemarkerServlet.KEY_REQUEST_PRIVATE);
        if(reqHash instanceof HttpRequestHashModel) {
            HttpServletRequest req  = 
                ((HttpRequestHashModel)reqHash).getRequest();
            String pi = req.getPathInfo();
            String reqPath = req.getServletPath();
            if(reqPath == null) {
                reqPath = "";
            }
            reqPath += (pi == null ? "" : pi);
            // We don't care about paths with ".." in them. If the container
            // wishes to resolve them on its own, let it be.
            int lastSlash = reqPath.lastIndexOf('/');
            if(lastSlash != -1) {
                return reqPath.substring(0, lastSlash + 1) + uri;
            }
            else {
                return '/' + uri;
            }
        }
        throw new TemplateModelException(
            "Can't resolve relative URI " + uri + 
            " as request URL information is unavailable.");
    }
    
    private static final class TldParser extends DefaultHandler {
        private final Map tags = new HashMap();
        private final List listeners = new ArrayList();
        
        private Locator locator;
        private StringBuffer buf;
        private String tagName;
        private String tagClass;

        Map getTags() {
            return tags;
        }

        List getListeners() {
            return listeners;
        }
                
        public void setDocumentLocator(Locator locator) {
            this.locator = locator;
        }

        public void startElement(
            String nsuri,
            String localName,
            String qName,
            Attributes atts) {
            if ("name".equals(qName) || "tagclass".equals(qName) || "tag-class".equals(qName) || "listener-class".equals(qName)) {
                buf = new StringBuffer();
            }
        }

        public void characters(char[] chars, int off, int len) {
            if (buf != null) {
                buf.append(chars, off, len);
            }
        }

        public void endElement(String nsuri, String localName, String qName)
            throws SAXParseException {
            if ("name".equals(qName)) {
                if(tagName == null) {
                    tagName = buf.toString().trim();
                }
                buf = null;
            }
            else if ("tagclass".equals(qName) || "tag-class".equals(qName)) {
                tagClass = buf.toString().trim();
                buf = null;
            }
            else if ("tag".equals(qName)) {
                try {
                    tags.put(
                        tagName,
                        new TagTransformModel(ClassUtil.forName(tagClass)));
                    tagName = null;
                    tagClass = null;
                }
                catch (IntrospectionException e) {
                    throw new SAXParseException(
                        "Can't introspect tag class " + tagClass,
                        locator,
                        e);
                }
                catch (ClassNotFoundException e) {
                    throw new SAXParseException(
                        "Can't find tag class " + tagClass,
                        locator,
                        e);
                }
            }
            else if ("listener-class".equals(qName)) {
                String listenerClass = buf.toString().trim();
                buf = null;
                try {
                    listeners.add(ClassUtil.forName(listenerClass).newInstance());
                }
                catch(Exception e) {
                    throw new SAXParseException(
                        "Can't instantiate listener class " + listenerClass,
                        locator,
                        e);
                }
            }
        }
    }

    private static final Map dtds = new HashMap();
    static
    {
        // JSP taglib 2.0
        dtds.put("http://java.sun.com/xml/ns/j2ee/web-jsptaglibrary_2_0.xsd", "web-jsptaglibrary_2_0.xsd");
        // JSP taglib 1.2
        dtds.put("-//Sun Microsystems, Inc.//DTD JSP Tag Library 1.2//EN", "web-jsptaglibrary_1_2.dtd");
        dtds.put("http://java.sun.com/dtd/web-jsptaglibrary_1_2.dtd", "web-jsptaglibrary_1_2.dtd");
        // JSP taglib 1.1
        dtds.put("-//Sun Microsystems, Inc.//DTD JSP Tag Library 1.1//EN", "web-jsptaglibrary_1_1.dtd");
        dtds.put("http://java.sun.com/j2ee/dtds/web-jsptaglibrary_1_1.dtd", "web-jsptaglibrary_1_1.dtd");
        // Servlet 2.4
        dtds.put("http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd", "web-app_2_4.xsd");
        // Servlet 2.3
        dtds.put("-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN", "web-app_2_3.dtd");
        dtds.put("http://java.sun.com/dtd/web-app_2_3.dtd", "web-app_2_3.dtd");
        // Servlet 2.2
        dtds.put("-//Sun Microsystems, Inc.//DTD Web Application 2.2//EN", "web-app_2_2.dtd");
        dtds.put("http://java.sun.com/j2ee/dtds/web-app_2_2.dtd", "web-app_2_2.dtd");
    }
    private static final class LocalTaglibDtds implements EntityResolver {
        public InputSource resolveEntity(String publicId, String systemId)
        {
            String resourceName = (String)dtds.get(publicId);
            if(resourceName == null)
            {
                resourceName = (String)dtds.get(systemId);
            }
            InputStream resourceStream;
            if(resourceName != null)
            {
                resourceStream = getClass().getResourceAsStream(resourceName);
            }
            else
            {
                // Fake an empty stream for unknown DTDs 
                resourceStream = new ByteArrayInputStream(new byte[0]);
            }
            InputSource is = new InputSource();
            is.setPublicId(publicId);
            is.setSystemId(systemId);
            is.setByteStream(resourceStream);
            return is;
        }
    }
}