jdk/src/share/classes/java/util/XMLUtils.java
changeset 2 90ce3da70b43
child 5506 202f599c92aa
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/src/share/classes/java/util/XMLUtils.java	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,207 @@
+/*
+ * Copyright 2003-2004 Sun Microsystems, Inc.  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.  Sun designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+package java.util;
+
+import java.io.*;
+import org.xml.sax.*;
+import org.xml.sax.helpers.*;
+import org.w3c.dom.*;
+import javax.xml.parsers.*;
+import javax.xml.transform.*;
+import javax.xml.transform.dom.*;
+import javax.xml.transform.stream.*;
+
+/**
+ * A class used to aid in Properties load and save in XML. Keeping this
+ * code outside of Properties helps reduce the number of classes loaded
+ * when Properties is loaded.
+ *
+ * @author  Michael McCloskey
+ * @since   1.3
+ */
+class XMLUtils {
+
+    // XML loading and saving methods for Properties
+
+    // The required DTD URI for exported properties
+    private static final String PROPS_DTD_URI =
+    "http://java.sun.com/dtd/properties.dtd";
+
+    private static final String PROPS_DTD =
+    "<?xml version=\"1.0\" encoding=\"UTF-8\"?>" +
+    "<!-- DTD for properties -->"                +
+    "<!ELEMENT properties ( comment?, entry* ) >"+
+    "<!ATTLIST properties"                       +
+        " version CDATA #FIXED \"1.0\">"         +
+    "<!ELEMENT comment (#PCDATA) >"              +
+    "<!ELEMENT entry (#PCDATA) >"                +
+    "<!ATTLIST entry "                           +
+        " key CDATA #REQUIRED>";
+
+    /**
+     * Version number for the format of exported properties files.
+     */
+    private static final String EXTERNAL_XML_VERSION = "1.0";
+
+    static void load(Properties props, InputStream in)
+        throws IOException, InvalidPropertiesFormatException
+    {
+        Document doc = null;
+        try {
+            doc = getLoadingDoc(in);
+        } catch (SAXException saxe) {
+            throw new InvalidPropertiesFormatException(saxe);
+        }
+        Element propertiesElement = (Element)doc.getChildNodes().item(1);
+        String xmlVersion = propertiesElement.getAttribute("version");
+        if (xmlVersion.compareTo(EXTERNAL_XML_VERSION) > 0)
+            throw new InvalidPropertiesFormatException(
+                "Exported Properties file format version " + xmlVersion +
+                " is not supported. This java installation can read" +
+                " versions " + EXTERNAL_XML_VERSION + " or older. You" +
+                " may need to install a newer version of JDK.");
+        importProperties(props, propertiesElement);
+    }
+
+    static Document getLoadingDoc(InputStream in)
+        throws SAXException, IOException
+    {
+        DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
+        dbf.setIgnoringElementContentWhitespace(true);
+        dbf.setValidating(true);
+        dbf.setCoalescing(true);
+        dbf.setIgnoringComments(true);
+        try {
+            DocumentBuilder db = dbf.newDocumentBuilder();
+            db.setEntityResolver(new Resolver());
+            db.setErrorHandler(new EH());
+            InputSource is = new InputSource(in);
+            return db.parse(is);
+        } catch (ParserConfigurationException x) {
+            throw new Error(x);
+        }
+    }
+
+    static void importProperties(Properties props, Element propertiesElement) {
+        NodeList entries = propertiesElement.getChildNodes();
+        int numEntries = entries.getLength();
+        int start = numEntries > 0 &&
+            entries.item(0).getNodeName().equals("comment") ? 1 : 0;
+        for (int i=start; i<numEntries; i++) {
+            Element entry = (Element)entries.item(i);
+            if (entry.hasAttribute("key")) {
+                Node n = entry.getFirstChild();
+                String val = (n == null) ? "" : n.getNodeValue();
+                props.setProperty(entry.getAttribute("key"), val);
+            }
+        }
+    }
+
+    static void save(Properties props, OutputStream os, String comment,
+                     String encoding)
+        throws IOException
+    {
+        DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
+        DocumentBuilder db = null;
+        try {
+            db = dbf.newDocumentBuilder();
+        } catch (ParserConfigurationException pce) {
+            assert(false);
+        }
+        Document doc = db.newDocument();
+        Element properties =  (Element)
+            doc.appendChild(doc.createElement("properties"));
+
+        if (comment != null) {
+            Element comments = (Element)properties.appendChild(
+                doc.createElement("comment"));
+            comments.appendChild(doc.createTextNode(comment));
+        }
+
+        Set keys = props.keySet();
+        Iterator i = keys.iterator();
+        while(i.hasNext()) {
+            String key = (String)i.next();
+            Element entry = (Element)properties.appendChild(
+                doc.createElement("entry"));
+            entry.setAttribute("key", key);
+            entry.appendChild(doc.createTextNode(props.getProperty(key)));
+        }
+        emitDocument(doc, os, encoding);
+    }
+
+    static void emitDocument(Document doc, OutputStream os, String encoding)
+        throws IOException
+    {
+        TransformerFactory tf = TransformerFactory.newInstance();
+        Transformer t = null;
+        try {
+            t = tf.newTransformer();
+            t.setOutputProperty(OutputKeys.DOCTYPE_SYSTEM, PROPS_DTD_URI);
+            t.setOutputProperty(OutputKeys.INDENT, "yes");
+            t.setOutputProperty(OutputKeys.METHOD, "xml");
+            t.setOutputProperty(OutputKeys.ENCODING, encoding);
+        } catch (TransformerConfigurationException tce) {
+            assert(false);
+        }
+        DOMSource doms = new DOMSource(doc);
+        StreamResult sr = new StreamResult(os);
+        try {
+            t.transform(doms, sr);
+        } catch (TransformerException te) {
+            IOException ioe = new IOException();
+            ioe.initCause(te);
+            throw ioe;
+        }
+    }
+
+    private static class Resolver implements EntityResolver {
+        public InputSource resolveEntity(String pid, String sid)
+            throws SAXException
+        {
+            if (sid.equals(PROPS_DTD_URI)) {
+                InputSource is;
+                is = new InputSource(new StringReader(PROPS_DTD));
+                is.setSystemId(PROPS_DTD_URI);
+                return is;
+            }
+            throw new SAXException("Invalid system identifier: " + sid);
+        }
+    }
+
+    private static class EH implements ErrorHandler {
+        public void error(SAXParseException x) throws SAXException {
+            throw x;
+        }
+        public void fatalError(SAXParseException x) throws SAXException {
+            throw x;
+        }
+        public void warning(SAXParseException x) throws SAXException {
+            throw x;
+        }
+    }
+
+}