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1
7
8 package java.util;
9
10 import java.io.*;
11 import org.xml.sax.*;
12 import org.xml.sax.helpers.*;
13 import org.w3c.dom.*;
14 import javax.xml.parsers.*;
15 import javax.xml.transform.*;
16 import javax.xml.transform.dom.*;
17 import javax.xml.transform.stream.*;
18
19
28 class XMLUtils {
29
30
32 private static final String  PROPS_DTD_URI =
34 "http://java.sun.com/dtd/properties.dtd";
35
36 private static final String PROPS_DTD =
37 "<?xml version=\"1.0\" encoding=\"UTF-8\"?>" +
38 "<!-- DTD for properties -->" +
39 "<!ELEMENT properties ( comment?, entry* ) >"+
40 "<!ATTLIST properties" +
41 " version CDATA #FIXED \"1.0\">" +
42 "<!ELEMENT comment (#PCDATA) >" +
43 "<!ELEMENT entry (#PCDATA) >" +
44 "<!ATTLIST entry " +
45 " key CDATA #REQUIRED>";
46
47
50 private static final String EXTERNAL_XML_VERSION = "1.0";
51
52 static void load(Properties props, InputStream in)
53 throws IOException, InvalidPropertiesFormatException
54 {
55 Document doc = null;
56 try {
57 doc = getLoadingDoc(in);
58 } catch (SAXException saxe) {
59 throw new InvalidPropertiesFormatException (saxe);
60 }
61 Element propertiesElement = (Element)doc.getChildNodes().item(1);
62 String xmlVersion = propertiesElement.getAttribute("version");
63 if (xmlVersion.compareTo(EXTERNAL_XML_VERSION) > 0)
64 throw new InvalidPropertiesFormatException (
65 "Exported Properties file format version " + xmlVersion +
66 " is not supported. This java installation can read" +
67 " versions " + EXTERNAL_XML_VERSION + " or older. You" +
68 " may need to install a newer version of JDK.");
69 importProperties(props, propertiesElement);
70 }
71
72 static Document getLoadingDoc(InputStream in)
73 throws SAXException, IOException
74 {
75 DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
76 dbf.setIgnoringElementContentWhitespace(true);
77 dbf.setValidating(true);
78 dbf.setCoalescing(true);
79 dbf.setIgnoringComments(true);
80 try {
81 DocumentBuilder db = dbf.newDocumentBuilder();
82 db.setEntityResolver(new Resolver());
83 db.setErrorHandler(new EH());
84 InputSource is = new InputSource(in);
85 return db.parse(is);
86 } catch (ParserConfigurationException x) {
87 throw new Error (x);
88 }
89 }
90
91 static void importProperties(Properties props, Element propertiesElement) {
92 NodeList entries = propertiesElement.getChildNodes();
93 int numEntries = entries.getLength();
94 int start = numEntries > 0 &&
95 entries.item(0).getNodeName().equals("comment") ? 1 : 0;
96 for (int i=start; i<numEntries; i++) {
97 Element entry = (Element)entries.item(i);
98 if (entry.hasAttribute("key")) {
99 Node n = entry.getFirstChild();
100 String val = (n == null) ? "" : n.getNodeValue();
101 props.setProperty(entry.getAttribute("key"), val);
102 }
103 }
104 }
105
106 static void save(Properties props, OutputStream os, String comment,
107 String encoding)
108 throws IOException
109 {
110 DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
111 DocumentBuilder db = null;
112 try {
113 db = dbf.newDocumentBuilder();
114 } catch (ParserConfigurationException pce) {
115 assert(false);
116 }
117 Document doc = db.newDocument();
118 Element properties = (Element)
119 doc.appendChild(doc.createElement("properties"));
120
121 if (comment != null) {
122 Element comments = (Element)properties.appendChild(
123 doc.createElement("comment"));
124 comments.appendChild(doc.createTextNode(comment));
125 }
126
127 Set keys = props.keySet();
128 Iterator i = keys.iterator();
129 while(i.hasNext()) {
130 String key = (String )i.next();
131 Element entry = (Element)properties.appendChild(
132 doc.createElement("entry"));
133 entry.setAttribute("key", key);
134 entry.appendChild(doc.createTextNode(props.getProperty(key)));
135 }
136 emitDocument(doc, os, encoding);
137 }
138
139 static void emitDocument(Document doc, OutputStream os, String encoding)
140 throws IOException
141 {
142 TransformerFactory tf = TransformerFactory.newInstance();
143 Transformer t = null;
144 try {
145 t = tf.newTransformer();
146 t.setOutputProperty(OutputKeys.DOCTYPE_SYSTEM, PROPS_DTD_URI);
147 t.setOutputProperty(OutputKeys.INDENT, "yes");
148 t.setOutputProperty(OutputKeys.METHOD, "xml");
149 t.setOutputProperty(OutputKeys.ENCODING, encoding);
150 } catch (TransformerConfigurationException tce) {
151 assert(false);
152 }
153 DOMSource doms = new DOMSource(doc);
154 StreamResult sr = new StreamResult(os);
155 try {
156 t.transform(doms, sr);
157 } catch (TransformerException te) {
158 IOException ioe = new IOException();
159 ioe.initCause(te);
160 throw ioe;
161 }
162 }
163
164 private static class Resolver implements EntityResolver {
165 public InputSource resolveEntity(String pid, String sid)
166 throws SAXException
167 {
168 if (sid.equals(PROPS_DTD_URI)) {
169 InputSource is;
170 is = new InputSource(new StringReader(PROPS_DTD));
171 is.setSystemId(PROPS_DTD_URI);
172 return is;
173 }
174 throw new SAXException("Invalid system identifier: " + sid);
175 }
176 }
177
178 private static class EH implements ErrorHandler {
179 public void error(SAXParseException x) throws SAXException {
180 throw x;
181 }
182 public void fatalError(SAXParseException x) throws SAXException {
183 throw x;
184 }
185 public void warning(SAXParseException x) throws SAXException {
186 throw x;
187 }
188 }
189
190 }
191 |
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