1 /*
2  * Copyright (C) 2014 The Android Open Source Project
3  * Copyright (c) 2003, 2011, Oracle and/or its affiliates. All rights reserved.
4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5  *
6  * This code is free software; you can redistribute it and/or modify it
7  * under the terms of the GNU General Public License version 2 only, as
8  * published by the Free Software Foundation.  Oracle designates this
9  * particular file as subject to the "Classpath" exception as provided
10  * by Oracle in the LICENSE file that accompanied this code.
11  *
12  * This code is distributed in the hope that it will be useful, but WITHOUT
13  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
15  * version 2 for more details (a copy is included in the LICENSE file that
16  * accompanied this code).
17  *
18  * You should have received a copy of the GNU General Public License version
19  * 2 along with this work; if not, write to the Free Software Foundation,
20  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
21  *
22  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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24  * questions.
25  */
26 
27 package java.util;
28 
29 import java.io.*;
30 import org.xml.sax.*;
31 import org.xml.sax.helpers.*;
32 import org.w3c.dom.*;
33 import javax.xml.parsers.*;
34 import javax.xml.transform.*;
35 import javax.xml.transform.dom.*;
36 import javax.xml.transform.stream.*;
37 
38 /**
39  * A class used to aid in Properties load and save in XML. Keeping this
40  * code outside of Properties helps reduce the number of classes loaded
41  * when Properties is loaded.
42  *
43  * @author  Michael McCloskey
44  * @since   1.3
45  */
46 class XMLUtils {
47 
48     // XML loading and saving methods for Properties
49 
50     // The required DTD URI for exported properties
51     private static final String PROPS_DTD_URI =
52     "http://java.sun.com/dtd/properties.dtd";
53 
54     private static final String PROPS_DTD =
55     "<?xml version=\"1.0\" encoding=\"UTF-8\"?>" +
56     "<!-- DTD for properties -->"                +
57     "<!ELEMENT properties ( comment?, entry* ) >"+
58     "<!ATTLIST properties"                       +
59         " version CDATA #FIXED \"1.0\">"         +
60     "<!ELEMENT comment (#PCDATA) >"              +
61     "<!ELEMENT entry (#PCDATA) >"                +
62     "<!ATTLIST entry "                           +
63         " key CDATA #REQUIRED>";
64 
65     /**
66      * Version number for the format of exported properties files.
67      */
68     private static final String EXTERNAL_XML_VERSION = "1.0";
69 
load(Properties props, InputStream in)70     static void load(Properties props, InputStream in)
71         throws IOException, InvalidPropertiesFormatException
72     {
73         Document doc = null;
74         try {
75             doc = getLoadingDoc(in);
76         } catch (SAXException saxe) {
77             throw new InvalidPropertiesFormatException(saxe);
78         }
79         Element propertiesElement = doc.getDocumentElement();
80         String xmlVersion = propertiesElement.getAttribute("version");
81         if (xmlVersion.compareTo(EXTERNAL_XML_VERSION) > 0)
82             throw new InvalidPropertiesFormatException(
83                 "Exported Properties file format version " + xmlVersion +
84                 " is not supported. This java installation can read" +
85                 " versions " + EXTERNAL_XML_VERSION + " or older. You" +
86                 " may need to install a newer version of JDK.");
87         importProperties(props, propertiesElement);
88     }
89 
getLoadingDoc(InputStream in)90     static Document getLoadingDoc(InputStream in)
91         throws SAXException, IOException
92     {
93         DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
94         dbf.setIgnoringElementContentWhitespace(true);
95         // Android-changed: We don't currently have a validating document builder.
96         // Revert this if the situation changes.
97         //
98         // dbf.setValidating(true);
99         dbf.setCoalescing(true);
100         dbf.setIgnoringComments(true);
101         try {
102             DocumentBuilder db = dbf.newDocumentBuilder();
103             db.setEntityResolver(new Resolver());
104             db.setErrorHandler(new EH());
105             InputSource is = new InputSource(in);
106             return db.parse(is);
107         } catch (ParserConfigurationException x) {
108             throw new Error(x);
109         }
110     }
111 
importProperties(Properties props, Element propertiesElement)112     static void importProperties(Properties props, Element propertiesElement) {
113         NodeList entries = propertiesElement.getChildNodes();
114         int numEntries = entries.getLength();
115         int start = numEntries > 0 &&
116             entries.item(0).getNodeName().equals("comment") ? 1 : 0;
117         for (int i=start; i<numEntries; i++) {
118             // Android-changed: Exclude CDATA nodes and the like.
119             if (!(entries.item(i) instanceof Element)) {
120                 continue;
121             }
122             Element entry = (Element)entries.item(i);
123             if (entry.hasAttribute("key")) {
124                 Node n = entry.getFirstChild();
125                 String val = (n == null) ? "" : n.getNodeValue();
126                 props.setProperty(entry.getAttribute("key"), val);
127             }
128         }
129     }
130 
save(Properties props, OutputStream os, String comment, String encoding)131     static void save(Properties props, OutputStream os, String comment,
132                      String encoding)
133         throws IOException
134     {
135         DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
136         DocumentBuilder db = null;
137         try {
138             db = dbf.newDocumentBuilder();
139         } catch (ParserConfigurationException pce) {
140             assert(false);
141         }
142         Document doc = db.newDocument();
143         Element properties =  (Element)
144             doc.appendChild(doc.createElement("properties"));
145 
146         if (comment != null) {
147             Element comments = (Element)properties.appendChild(
148                 doc.createElement("comment"));
149             comments.appendChild(doc.createTextNode(comment));
150         }
151 
152         synchronized (props) {
153             for (String key : props.stringPropertyNames()) {
154                 Element entry = (Element)properties.appendChild(
155                     doc.createElement("entry"));
156                 entry.setAttribute("key", key);
157                 entry.appendChild(doc.createTextNode(props.getProperty(key)));
158             }
159         }
160         emitDocument(doc, os, encoding);
161     }
162 
emitDocument(Document doc, OutputStream os, String encoding)163     static void emitDocument(Document doc, OutputStream os, String encoding)
164         throws IOException
165     {
166         TransformerFactory tf = TransformerFactory.newInstance();
167         Transformer t = null;
168         try {
169             t = tf.newTransformer();
170             t.setOutputProperty(OutputKeys.DOCTYPE_SYSTEM, PROPS_DTD_URI);
171             t.setOutputProperty(OutputKeys.INDENT, "yes");
172             t.setOutputProperty(OutputKeys.METHOD, "xml");
173             t.setOutputProperty(OutputKeys.ENCODING, encoding);
174         } catch (TransformerConfigurationException tce) {
175             assert(false);
176         }
177         DOMSource doms = new DOMSource(doc);
178         StreamResult sr = new StreamResult(os);
179         try {
180             t.transform(doms, sr);
181         } catch (TransformerException te) {
182             IOException ioe = new IOException();
183             ioe.initCause(te);
184             throw ioe;
185         }
186     }
187 
188     private static class Resolver implements EntityResolver {
resolveEntity(String pid, String sid)189         public InputSource resolveEntity(String pid, String sid)
190             throws SAXException
191         {
192             if (sid.equals(PROPS_DTD_URI)) {
193                 InputSource is;
194                 is = new InputSource(new StringReader(PROPS_DTD));
195                 is.setSystemId(PROPS_DTD_URI);
196                 return is;
197             }
198             throw new SAXException("Invalid system identifier: " + sid);
199         }
200     }
201 
202     private static class EH implements ErrorHandler {
error(SAXParseException x)203         public void error(SAXParseException x) throws SAXException {
204             throw x;
205         }
fatalError(SAXParseException x)206         public void fatalError(SAXParseException x) throws SAXException {
207             throw x;
208         }
warning(SAXParseException x)209         public void warning(SAXParseException x) throws SAXException {
210             throw x;
211         }
212     }
213 
214 }
215