Java tutorial
/* * Copyright (c) 1998, 2014, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package javax.swing.text.html.parser; import sun.awt.AppContext; import javax.swing.text.html.HTMLEditorKit; import java.io.BufferedInputStream; import java.io.IOException; import java.io.InputStream; import java.io.DataInputStream; import java.io.ObjectInputStream; import java.io.Reader; import java.io.Serializable; import java.security.AccessController; import java.security.PrivilegedAction; /** * Responsible for starting up a new DocumentParser * each time its parse method is invoked. Stores a * reference to the dtd. * * @author Sunita Mani */ @SuppressWarnings("serial") // Same-version serialization only public class ParserDelegator extends HTMLEditorKit.Parser implements Serializable { private static final Object DTD_KEY = new Object(); /** * Sets the default DTD. */ protected static void setDefaultDTD() { getDefaultDTD(); } private static synchronized DTD getDefaultDTD() { AppContext appContext = AppContext.getAppContext(); DTD dtd = (DTD) appContext.get(DTD_KEY); if (dtd == null) { DTD _dtd = null; // (PENDING) Hate having to hard code! String nm = "html32"; try { _dtd = DTD.getDTD(nm); } catch (IOException e) { // (PENDING) UGLY! System.out.println("Throw an exception: could not get default dtd: " + nm); } dtd = createDTD(_dtd, nm); appContext.put(DTD_KEY, dtd); } return dtd; } /** * Recreates a DTD from an archived format with the specified {@code name}. * * @param dtd a DTD * @param name the name of the resource, relative to the ParserDelegator class. * @return the DTD with the specified {@code name}. */ protected static DTD createDTD(DTD dtd, String name) { InputStream in = null; boolean debug = true; try { String path = name + ".bdtd"; in = getResourceAsStream(path); if (in != null) { dtd.read(new DataInputStream(new BufferedInputStream(in))); DTD.putDTDHash(name, dtd); } } catch (Exception e) { System.out.println(e); } return dtd; } /** * Creates {@code ParserDelegator} with default DTD. */ public ParserDelegator() { setDefaultDTD(); } public void parse(Reader r, HTMLEditorKit.ParserCallback cb, boolean ignoreCharSet) throws IOException { new DocumentParser(getDefaultDTD()).parse(r, cb, ignoreCharSet); } /** * Fetch a resource relative to the ParserDelegator classfile. * If this is called on 1.2 the loading will occur under the * protection of a doPrivileged call to allow the ParserDelegator * to function when used in an applet. * * @param name the name of the resource, relative to the * ParserDelegator class. * @return a stream representing the resource */ static InputStream getResourceAsStream(final String name) { return AccessController.doPrivileged(new PrivilegedAction<InputStream>() { public InputStream run() { return ParserDelegator.class.getResourceAsStream(name); } }); } private void readObject(ObjectInputStream s) throws ClassNotFoundException, IOException { s.defaultReadObject(); setDefaultDTD(); } }