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1
40
41 package com.sun.jmx.examples.scandir.config;
42
43 import java.io.ByteArrayInputStream  ;
44 import java.io.ByteArrayOutputStream ;
45 import java.io.File ;
46 import java.io.FileOutputStream ;
47 import java.io.IOException ;
48 import java.io.InputStream ;
49 import java.io.OutputStream ;
50 import java.util.logging.Logger ;
51 import javax.xml.bind.JAXBContext;
52 import javax.xml.bind.JAXBException;
53 import javax.xml.bind.Marshaller;
54 import javax.xml.bind.Unmarshaller;
55
56
62 public class XmlConfigUtils {
63
64
69 public static final String NAMESPACE =
70 "jmx:com.sun.jmx.examples.scandir.config";
71
74 private static final Logger LOG =
75 Logger.getLogger(XmlConfigUtils.class.getName());
76
77 private static JAXBContext context;
79
80 final String file;
83
84
89 public XmlConfigUtils(String file) {
90 this.file = file;
91 }
92
93
103 public synchronized void writeToFile(ScanManagerConfig bean)
104 throws IOException {
105
106 final File f = newXmlTmpFile(file);
108 try {
109 final FileOutputStream out = new FileOutputStream (f);
110 boolean failed = true;
111 try {
112 write(bean,out,false);
114
115 failed = false;
117 } finally {
118 out.close();
119 if (failed == true) f.delete();
121 }
122
123 commit(file,f);
125 } catch (JAXBException x) {
126 final IOException io =
127 new IOException ("Failed to write SessionConfigBean to " +
128 file+": "+x,x);
129 throw io;
130 }
131 }
132
133
139 public static String toString(Object bean) {
140 try {
141 final ByteArrayOutputStream baos = new ByteArrayOutputStream ();
142 final Marshaller m = createMarshaller();
143 m.setProperty(m.JAXB_FRAGMENT,Boolean.TRUE);
144 m.marshal(bean, baos);
145 return baos.toString();
146 } catch (JAXBException x) {
147 final IllegalArgumentException iae =
148 new IllegalArgumentException (
149 "Failed to write SessionConfigBean: "+x,x);
150 throw iae;
151 }
152 }
153
154
165 public static ScanManagerConfig xmlClone(ScanManagerConfig bean) {
166 final Object clone = copy(bean);
167 return (ScanManagerConfig)clone;
168 }
169
170
180 private static Object copy(Object bean) {
181 try {
182 final ByteArrayOutputStream baos = new ByteArrayOutputStream ();
183 final Marshaller m = createMarshaller();
184 m.marshal(bean, baos);
185 final ByteArrayInputStream bais =
186 new ByteArrayInputStream (baos.toByteArray());
187 return createUnmarshaller().unmarshal(bais);
188 } catch (JAXBException x) {
189 final IllegalArgumentException iae =
190 new IllegalArgumentException ("Failed to write SessionConfigBean: "+x,x);
191 throw iae;
192 }
193 }
194
195
206 public static DirectoryScannerConfig xmlClone(DirectoryScannerConfig bean) {
207 final Object clone = copy(bean);
208 return (DirectoryScannerConfig)clone;
209 }
210
211
217 public synchronized ScanManagerConfig readFromFile() throws IOException {
218 final File f = new File (file);
219 if (!f.exists())
220 throw new IOException ("No such file: "+file);
221 if (!f.canRead())
222 throw new IOException ("Can't read file: "+file);
223 try {
224 return read(f);
225 } catch (JAXBException x) {
226 final IOException io =
227 new IOException ("Failed to read SessionConfigBean from " +
228 file+": "+x,x);
229 throw io;
230 }
231 }
232
233
240 public static ScanManagerConfig read(File f)
241 throws JAXBException {
242 final Unmarshaller u = createUnmarshaller();
243 return (ScanManagerConfig) u.unmarshal(f);
244
245 }
246
247
256 public static void write(ScanManagerConfig bean, OutputStream os,
257 boolean fragment)
258 throws JAXBException {
259 writeXml((Object )bean,os,fragment);
260 }
261
262
271 public static void write(ResultRecord bean, OutputStream os, boolean fragment)
272 throws JAXBException {
273 writeXml((Object )bean,os,fragment);
274 }
275
276
285 private static void writeXml(Object bean, OutputStream os, boolean fragment)
286 throws JAXBException {
287 final Marshaller m = createMarshaller();
288 if (fragment) m.setProperty(m.JAXB_FRAGMENT,Boolean.TRUE);
289 m.marshal(bean,os);
290 }
291
292 private static Unmarshaller createUnmarshaller() throws JAXBException {
294 return getContext().createUnmarshaller();
295 }
296
297 private static Marshaller createMarshaller() throws JAXBException {
299 final Marshaller m = getContext().createMarshaller();
300 m.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT,Boolean.TRUE);
301 return m;
302 }
303
304 private static synchronized JAXBContext getContext() throws JAXBException {
310 if (context == null)
311 context = JAXBContext.newInstance(ScanManagerConfig.class,
312 ResultRecord.class);
313 return context;
314 }
315
316
317 private static File newXmlTmpFile(String basename) throws IOException {
335 final File f = new File (basename+".new");
336 if (!f.createNewFile())
337 throw new IOException ("file "+f.getName()+" already exists");
338
339 try {
340 final OutputStream newStream = new FileOutputStream (f);
341 try {
342 final String decl =
343 "<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"yes\"?>";
344 newStream.write(decl.getBytes("UTF-8"));
345 newStream.flush();
346 } finally {
347 newStream.close();
348 }
349 } catch (IOException x) {
350 f.delete();
351 throw x;
352 }
353 return f;
354 }
355
356 private static File commit(String basename, File tmpFile)
359 throws IOException {
360 try {
361 final String backupName = basename+"~";
362 final File desired = new File (basename);
363 final File backup = new File (backupName);
364 backup.delete();
365 if (desired.exists()) {
366 if (!desired.renameTo(new File (backupName)))
367 throw new IOException ("can't rename to "+backupName);
368 }
369 if (!tmpFile.renameTo(new File (basename)))
370 throw new IOException ("can't rename to "+basename);
371 } catch (IOException x) {
372 tmpFile.delete();
373 throw x;
374 }
375 return new File (basename);
376 }
377
378
389 public static File createNewXmlFile(String basename) throws IOException {
390 return commit(basename,newXmlTmpFile(basename));
391 }
392
393 }
394 |
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