1 /*
2 * Copyright (c) 2003, 2013, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
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19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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23 * questions.
24 */
25
26 package javax.sql.rowset.spi;
27
28 import java.util.logging.*;
29 import java.util.*;
30
31 import java.sql.*;
32 import javax.sql.*;
33
34 import java.io.FileInputStream;
35 import java.io.InputStream;
36 import java.io.IOException;
37 import java.io.FileNotFoundException;
38
39 import javax.naming.*;
40
41 /**
42 * The Service Provider Interface (SPI) mechanism that generates <code>SyncProvider</code>
43 * instances to be used by disconnected <code>RowSet</code> objects.
44 * The <code>SyncProvider</code> instances in turn provide the
45 * <code>javax.sql.RowSetReader</code> object the <code>RowSet</code> object
46 * needs to populate itself with data and the
47 * <code>javax.sql.RowSetWriter</code> object it needs to
48 * propagate changes to its
49 * data back to the underlying data source.
50 * <P>
51 * Because the methods in the <code>SyncFactory</code> class are all static,
52 * there is only one <code>SyncFactory</code> object
53 * per Java VM at any one time. This ensures that there is a single source from which a
54 * <code>RowSet</code> implementation can obtain its <code>SyncProvider</code>
55 * implementation.
56 * <p>
57 * <h3>1.0 Overview</h3>
58 * The <code>SyncFactory</code> class provides an internal registry of available
59 * synchronization provider implementations (<code>SyncProvider</code> objects).
60 * This registry may be queried to determine which
61 * synchronization providers are available.
62 * The following line of code gets an enumeration of the providers currently registered.
63 * <PRE>
64 * java.util.Enumeration e = SyncFactory.getRegisteredProviders();
65 * </PRE>
66 * All standard <code>RowSet</code> implementations must provide at least two providers:
67 * <UL>
68 * <LI>an optimistic provider for use with a <code>CachedRowSet</code> implementation
69 * or an implementation derived from it
70 * <LI>an XML provider, which is used for reading and writing XML, such as with
71 * <code>WebRowSet</code> objects
72 * </UL>
73 * Note that the JDBC RowSet Implementations include the <code>SyncProvider</code>
74 * implemtations <code>RIOptimisticProvider</code> and <code>RIXmlProvider</code>,
75 * which satisfy this requirement.
76 * <P>
77 * The <code>SyncFactory</code> class provides accessor methods to assist
78 * applications in determining which synchronization providers are currently
79 * registered with the <code>SyncFactory</code>.
80 * <p>
81 * Other methods let <code>RowSet</code> persistence providers be
82 * registered or de-registered with the factory mechanism. This
83 * allows additional synchronization provider implementations to be made
84 * available to <code>RowSet</code> objects at run time.
85 * <p>
86 * Applications can apply a degree of filtering to determine the level of
87 * synchronization that a <code>SyncProvider</code> implementation offers.
88 * The following criteria determine whether a provider is
89 * made available to a <code>RowSet</code> object:
90 * <ol>
91 * <li>If a particular provider is specified by a <code>RowSet</code> object, and
92 * the <code>SyncFactory</code> does not contain a reference to this provider,
93 * a <code>SyncFactoryException</code> is thrown stating that the synchronization
94 * provider could not be found.
95 * <p>
96 * <li>If a <code>RowSet</code> implementation is instantiated with a specified
97 * provider and the specified provider has been properly registered, the
98 * requested provider is supplied. Otherwise a <code>SyncFactoryException</code>
99 * is thrown.
100 * <p>
101 * <li>If a <code>RowSet</code> object does not specify a
102 * <code>SyncProvider</code> implementation and no additional
103 * <code>SyncProvider</code> implementations are available, the reference
104 * implementation providers are supplied.
105 * </ol>
106 * <h3>2.0 Registering <code>SyncProvider</code> Implementations</h3>
107 * <p>
108 * Both vendors and developers can register <code>SyncProvider</code>
109 * implementations using one of the following mechanisms.
110 * <ul>
111 * <LI><B>Using the command line</B><BR>
112 * The name of the provider is supplied on the command line, which will add
113 * the provider to the system properties.
114 * For example:
115 * <PRE>
116 * -Drowset.provider.classname=com.fred.providers.HighAvailabilityProvider
117 * </PRE>
118 * <li><b>Using the Standard Properties File</b><BR>
119 * The reference implementation is targeted
120 * to ship with J2SE 1.5, which will include an additional resource file
121 * that may be edited by hand. Here is an example of the properties file
122 * included in the reference implementation:
123 * <PRE>
124 * #Default JDBC RowSet sync providers listing
125 * #
126 *
127 * # Optimistic synchronization provider
128 * rowset.provider.classname.0=com.sun.rowset.providers.RIOptimisticProvider
129 * rowset.provider.vendor.0=Oracle Corporation
130 * rowset.provider.version.0=1.0
131 *
132 * # XML Provider using standard XML schema
133 * rowset.provider.classname.1=com.sun.rowset.providers.RIXMLProvider
134 * rowset.provider.vendor.1=Oracle Corporation
135 * rowset.provider.version.1=1.0
136 * </PRE>
137 * The <code>SyncFactory</code> checks this file and registers the
138 * <code>SyncProvider</code> implementations that it contains. A
139 * developer or vendor can add other implementations to this file.
140 * For example, here is a possible addition:
141 * <PRE>
142 * rowset.provider.classname.2=com.fred.providers.HighAvailabilityProvider
143 * rowset.provider.vendor.2=Fred, Inc.
144 * rowset.provider.version.2=1.0
145 * </PRE>
146 * <p>
147 * <li><b>Using a JNDI Context</b><BR>
148 * Available providers can be registered on a JNDI
149 * context, and the <code>SyncFactory</code> will attempt to load
150 * <code>SyncProvider</code> implementations from that JNDI context.
151 * For example, the following code fragment registers a provider implementation
152 * on a JNDI context. This is something a deployer would normally do. In this
153 * example, <code>MyProvider</code> is being registered on a CosNaming
154 * namespace, which is the namespace used by J2EE resources.
155 * <PRE>
156 * import javax.naming.*;
157 *
158 * Hashtable svrEnv = new Hashtable();
159 * srvEnv.put(Context.INITIAL_CONTEXT_FACTORY, "CosNaming");
160 *
161 * Context ctx = new InitialContext(svrEnv);
162 * com.fred.providers.MyProvider = new MyProvider();
163 * ctx.rebind("providers/MyProvider", syncProvider);
164 * </PRE>
165 * </ul>
166 * Next, an application will register the JNDI context with the
167 * <code>SyncFactory</code> instance. This allows the <code>SyncFactory</code>
168 * to browse within the JNDI context looking for <code>SyncProvider</code>
169 * implementations.
170 * <PRE>
171 * Hashtable appEnv = new Hashtable();
172 * appEnv.put(Context.INITIAL_CONTEXT_FACTORY, "CosNaming");
173 * appEnv.put(Context.PROVIDER_URL, "iiop://hostname/providers");
174 * Context ctx = new InitialContext(appEnv);
175 *
176 * SyncFactory.registerJNDIContext(ctx);
177 * </PRE>
178 * If a <code>RowSet</code> object attempts to obtain a <code>MyProvider</code>
179 * object, the <code>SyncFactory</code> will try to locate it. First it searches
180 * for it in the system properties, then it looks in the resource files, and
181 * finally it checks the JNDI context that has been set. The <code>SyncFactory</code>
182 * instance verifies that the requested provider is a valid extension of the
183 * <code>SyncProvider</code> abstract class and then gives it to the
184 * <code>RowSet</code> object. In the following code fragment, a new
185 * <code>CachedRowSet</code> object is created and initialized with
186 * <i>env</i>, which contains the binding to <code>MyProvider</code>.
187 * <PRE>
188 * Hashtable env = new Hashtable();
189 * env.put(SyncFactory.ROWSET_SYNC_PROVIDER, "com.fred.providers.MyProvider");
190 * CachedRowSet crs = new com.sun.rowset.CachedRowSetImpl(env);
191 * </PRE>
192 * Further details on these mechanisms are available in the
193 * <code>javax.sql.rowset.spi</code> package specification.
194 *
195 * @author Jonathan Bruce
196 * @see javax.sql.rowset.spi.SyncProvider
197 * @see javax.sql.rowset.spi.SyncFactoryException
198 */
199 public class SyncFactory {
200
201 /**
202 * Creates a new <code>SyncFactory</code> object, which is the singleton
203 * instance.
204 * Having a private constructor guarantees that no more than
205 * one <code>SyncProvider</code> object can exist at a time.
206 */
207 private SyncFactory() {
208 }
209
210 /**
211 * The standard property-id for a synchronization provider implementation
212 * name.
213 */
214 public static final String ROWSET_SYNC_PROVIDER =
215 "rowset.provider.classname";
216 /**
217 * The standard property-id for a synchronization provider implementation
218 * vendor name.
219 */
220 public static final String ROWSET_SYNC_VENDOR =
221 "rowset.provider.vendor";
222 /**
223 * The standard property-id for a synchronization provider implementation
224 * version tag.
225 */
226 public static final String ROWSET_SYNC_PROVIDER_VERSION =
227 "rowset.provider.version";
228 /**
229 * The standard resource file name.
230 */
231 private static String ROWSET_PROPERTIES = "rowset.properties";
232
233 /**
234 * Permission required to invoke setJNDIContext and setLogger
235 */
236 private static final SQLPermission SET_SYNCFACTORY_PERMISSION =
237 new SQLPermission("setSyncFactory");
238 /**
239 * The initial JNDI context where <code>SyncProvider</code> implementations can
240 * be stored and from which they can be invoked.
241 */
242 private static Context ic;
243 /**
244 * The <code>Logger</code> object to be used by the <code>SyncFactory</code>.
245 */
246 private static volatile Logger rsLogger;
247
248 /**
249 * The registry of available <code>SyncProvider</code> implementations.
250 * See section 2.0 of the class comment for <code>SyncFactory</code> for an
251 * explanation of how a provider can be added to this registry.
252 */
253 private static Hashtable<String, SyncProvider> implementations;
254
255 /**
256 * Adds the the given synchronization provider to the factory register. Guidelines
257 * are provided in the <code>SyncProvider</code> specification for the
258 * required naming conventions for <code>SyncProvider</code>
259 * implementations.
260 * <p>
261 * Synchronization providers bound to a JNDI context can be
262 * registered by binding a SyncProvider instance to a JNDI namespace.
263 *
264 * <pre>
265 * {@code
266 * SyncProvider p = new MySyncProvider();
267 * InitialContext ic = new InitialContext();
268 * ic.bind ("jdbc/rowset/MySyncProvider", p);
269 * } </pre>
270 *
271 * Furthermore, an initial JNDI context should be set with the
272 * <code>SyncFactory</code> using the <code>setJNDIContext</code> method.
273 * The <code>SyncFactory</code> leverages this context to search for
274 * available <code>SyncProvider</code> objects bound to the JNDI
275 * context and its child nodes.
276 *
277 * @param providerID A <code>String</code> object with the unique ID of the
278 * synchronization provider being registered
279 * @throws SyncFactoryException if an attempt is made to supply an empty
280 * or null provider name
281 * @see #setJNDIContext
282 */
283 public static synchronized void registerProvider(String providerID)
284 throws SyncFactoryException {
285
286 ProviderImpl impl = new ProviderImpl();
287 impl.setClassname(providerID);
288 initMapIfNecessary();
289 implementations.put(providerID, impl);
290
291 }
292
293 /**
294 * Returns the <code>SyncFactory</code> singleton.
295 *
296 * @return the <code>SyncFactory</code> instance
297 */
298 public static SyncFactory getSyncFactory() {
299 /*
300 * Using Initialization on Demand Holder idiom as
301 * Effective Java 2nd Edition,ITEM 71, indicates it is more performant
302 * than the Double-Check Locking idiom.
303 */
304 return SyncFactoryHolder.factory;
305 }
306
307 /**
308 * Removes the designated currently registered synchronization provider from the
309 * Factory SPI register.
310 *
311 * @param providerID The unique-id of the synchronization provider
312 * @throws SyncFactoryException If an attempt is made to
313 * unregister a SyncProvider implementation that was not registered.
314 */
315 public static synchronized void unregisterProvider(String providerID)
316 throws SyncFactoryException {
317 initMapIfNecessary();
318 if (implementations.containsKey(providerID)) {
319 implementations.remove(providerID);
320 }
321 }
322 private static String colon = ":";
323 private static String strFileSep = "/";
324
325 private static synchronized void initMapIfNecessary() throws SyncFactoryException {
326
327 // Local implementation class names and keys from Properties
328 // file, translate names into Class objects using Class.forName
329 // and store mappings
330 Properties properties = new Properties();
331
332 if (implementations == null) {
333 implementations = new Hashtable<>();
334
335 try {
336
337 // check if user is supplying his Synchronisation Provider
338 // Implementation if not using Oracle's implementation.
339 // properties.load(new FileInputStream(ROWSET_PROPERTIES));
340
341 // The rowset.properties needs to be in jdk/jre/lib when
342 // integrated with jdk.
343 // else it should be picked from -D option from command line.
344
345 // -Drowset.properties will add to standard properties. Similar
346 // keys will over-write
347
348 /*
349 * Dependent on application
350 */
351 String strRowsetProperties = System.getProperty("rowset.properties");
352 if (strRowsetProperties != null) {
353 // Load user's implementation of SyncProvider
354 // here. -Drowset.properties=/abc/def/pqr.txt
355 ROWSET_PROPERTIES = strRowsetProperties;
356 try (FileInputStream fis = new FileInputStream(ROWSET_PROPERTIES)) {
357 properties.load(fis);
358 }
359 parseProperties(properties);
360 }
361
362 /*
363 * Always available
364 */
365 ROWSET_PROPERTIES = "javax" + strFileSep + "sql" +
366 strFileSep + "rowset" + strFileSep +
367 "rowset.properties";
368
369 ClassLoader cl = Thread.currentThread().getContextClassLoader();
370
371 try (InputStream stream =
372 (cl == null) ? ClassLoader.getSystemResourceAsStream(ROWSET_PROPERTIES)
373 : cl.getResourceAsStream(ROWSET_PROPERTIES)) {
374 if (stream == null) {
375 throw new SyncFactoryException(
376 "Resource " + ROWSET_PROPERTIES + " not found");
377 }
378 properties.load(stream);
379 }
380
381 parseProperties(properties);
382
383 // removed else, has properties should sum together
384
385 } catch (FileNotFoundException e) {
386 throw new SyncFactoryException("Cannot locate properties file: " + e);
387 } catch (IOException e) {
388 throw new SyncFactoryException("IOException: " + e);
389 }
390
391 /*
392 * Now deal with -Drowset.provider.classname
393 * load additional properties from -D command line
394 */
395 properties.clear();
396 String providerImpls = System.getProperty(ROWSET_SYNC_PROVIDER);
397
398 if (providerImpls != null) {
399 int i = 0;
400 if (providerImpls.indexOf(colon) > 0) {
401 StringTokenizer tokenizer = new StringTokenizer(providerImpls, colon);
402 while (tokenizer.hasMoreElements()) {
403 properties.put(ROWSET_SYNC_PROVIDER + "." + i, tokenizer.nextToken());
404 i++;
405 }
406 } else {
407 properties.put(ROWSET_SYNC_PROVIDER, providerImpls);
408 }
409 parseProperties(properties);
410 }
411 }
412 }
413
414 /**
415 * The internal debug switch.
416 */
417 private static boolean debug = false;
418 /**
419 * Internal registry count for the number of providers contained in the
420 * registry.
421 */
422 private static int providerImplIndex = 0;
423
424 /**
425 * Internal handler for all standard property parsing. Parses standard
426 * ROWSET properties and stores lazy references into the the internal registry.
427 */
428 private static void parseProperties(Properties p) {
429
430 ProviderImpl impl = null;
431 String key = null;
432 String[] propertyNames = null;
433
434 for (Enumeration<?> e = p.propertyNames(); e.hasMoreElements();) {
435
436 String str = (String) e.nextElement();
437
438 int w = str.length();
439
440 if (str.startsWith(SyncFactory.ROWSET_SYNC_PROVIDER)) {
441
442 impl = new ProviderImpl();
443 impl.setIndex(providerImplIndex++);
444
445 if (w == (SyncFactory.ROWSET_SYNC_PROVIDER).length()) {
446 // no property index has been set.
447 propertyNames = getPropertyNames(false);
448 } else {
449 // property index has been set.
450 propertyNames = getPropertyNames(true, str.substring(w - 1));
451 }
452
453 key = p.getProperty(propertyNames[0]);
454 impl.setClassname(key);
455 impl.setVendor(p.getProperty(propertyNames[1]));
456 impl.setVersion(p.getProperty(propertyNames[2]));
457 implementations.put(key, impl);
458 }
459 }
460 }
461
462 /**
463 * Used by the parseProperties methods to disassemble each property tuple.
464 */
465 private static String[] getPropertyNames(boolean append) {
466 return getPropertyNames(append, null);
467 }
468
469 /**
470 * Disassembles each property and its associated value. Also handles
471 * overloaded property names that contain indexes.
472 */
473 private static String[] getPropertyNames(boolean append,
474 String propertyIndex) {
475 String dot = ".";
476 String[] propertyNames =
477 new String[]{SyncFactory.ROWSET_SYNC_PROVIDER,
478 SyncFactory.ROWSET_SYNC_VENDOR,
479 SyncFactory.ROWSET_SYNC_PROVIDER_VERSION};
480 if (append) {
481 for (int i = 0; i < propertyNames.length; i++) {
482 propertyNames[i] = propertyNames[i] +
483 dot +
484 propertyIndex;
485 }
486 return propertyNames;
487 } else {
488 return propertyNames;
489 }
490 }
491
492 /**
493 * Internal debug method that outputs the registry contents.
494 */
495 private static void showImpl(ProviderImpl impl) {
496 System.out.println("Provider implementation:");
497 System.out.println("Classname: " + impl.getClassname());
498 System.out.println("Vendor: " + impl.getVendor());
499 System.out.println("Version: " + impl.getVersion());
500 System.out.println("Impl index: " + impl.getIndex());
501 }
502
503 /**
504 * Returns the <code>SyncProvider</code> instance identified by <i>providerID</i>.
505 *
506 * @param providerID the unique identifier of the provider
507 * @return a <code>SyncProvider</code> implementation
508 * @throws SyncFactoryException If the SyncProvider cannot be found,
509 * the providerID is {@code null}, or
510 * some error was encountered when trying to invoke this provider.
511 */
512 public static SyncProvider getInstance(String providerID)
513 throws SyncFactoryException {
514
515 if(providerID == null) {
516 throw new SyncFactoryException("The providerID cannot be null");
517 }
518
519 initMapIfNecessary(); // populate HashTable
520 initJNDIContext(); // check JNDI context for any additional bindings
521
522 ProviderImpl impl = (ProviderImpl) implementations.get(providerID);
523
524 if (impl == null) {
525 // Requested SyncProvider is unavailable. Return default provider.
526 return new com.sun.rowset.providers.RIOptimisticProvider();
527 }
528
529 // Attempt to invoke classname from registered SyncProvider list
530 Class<?> c = null;
531 try {
532 ClassLoader cl = Thread.currentThread().getContextClassLoader();
533
534 /**
535 * The SyncProvider implementation of the user will be in
536 * the classpath. We need to find the ClassLoader which loads
537 * this SyncFactory and try to laod the SyncProvider class from
538 * there.
539 **/
540 c = Class.forName(providerID, true, cl);
541
542 if (c != null) {
543 return (SyncProvider) c.newInstance();
544 } else {
545 return new com.sun.rowset.providers.RIOptimisticProvider();
546 }
547
548 } catch (IllegalAccessException e) {
549 throw new SyncFactoryException("IllegalAccessException: " + e.getMessage());
550 } catch (InstantiationException e) {
551 throw new SyncFactoryException("InstantiationException: " + e.getMessage());
552 } catch (ClassNotFoundException e) {
553 throw new SyncFactoryException("ClassNotFoundException: " + e.getMessage());
554 }
555 }
556
557 /**
558 * Returns an Enumeration of currently registered synchronization
559 * providers. A <code>RowSet</code> implementation may use any provider in
560 * the enumeration as its <code>SyncProvider</code> object.
561 * <p>
562 * At a minimum, the reference synchronization provider allowing
563 * RowSet content data to be stored using a JDBC driver should be
564 * possible.
565 *
566 * @return Enumeration A enumeration of available synchronization
567 * providers that are registered with this Factory
568 * @throws SyncFactoryException If an error occurs obtaining the registered
569 * providers
570 */
571 public static Enumeration<SyncProvider> getRegisteredProviders()
572 throws SyncFactoryException {
573 initMapIfNecessary();
574 // return a collection of classnames
575 // of type SyncProvider
576 return implementations.elements();
577 }
578
579 /**
580 * Sets the logging object to be used by the <code>SyncProvider</code>
581 * implementation provided by the <code>SyncFactory</code>. All
582 * <code>SyncProvider</code> implementations can log their events to
583 * this object and the application can retrieve a handle to this
584 * object using the <code>getLogger</code> method.
585 * <p>
586 * This method checks to see that there is an {@code SQLPermission}
587 * object which grants the permission {@code setSyncFactory}
588 * before allowing the method to succeed. If a
589 * {@code SecurityManager} exists and its
590 * {@code checkPermission} method denies calling {@code setLogger},
591 * this method throws a
592 * {@code java.lang.SecurityException}.
593 *
594 * @param logger A Logger object instance
595 * @throws java.lang.SecurityException if a security manager exists and its
596 * {@code checkPermission} method denies calling {@code setLogger}
597 * @throws NullPointerException if the logger is null
598 * @see SecurityManager#checkPermission
599 */
600 public static void setLogger(Logger logger) {
601
602 SecurityManager sec = System.getSecurityManager();
603 if (sec != null) {
604 sec.checkPermission(SET_SYNCFACTORY_PERMISSION);
605 }
606
607 if(logger == null){
608 throw new NullPointerException("You must provide a Logger");
609 }
610 rsLogger = logger;
611 }
612
613 /**
614 * Sets the logging object that is used by <code>SyncProvider</code>
615 * implementations provided by the <code>SyncFactory</code> SPI. All
616 * <code>SyncProvider</code> implementations can log their events
617 * to this object and the application can retrieve a handle to this
618 * object using the <code>getLogger</code> method.
619 * <p>
620 * This method checks to see that there is an {@code SQLPermission}
621 * object which grants the permission {@code setSyncFactory}
622 * before allowing the method to succeed. If a
623 * {@code SecurityManager} exists and its
624 * {@code checkPermission} method denies calling {@code setLogger},
625 * this method throws a
626 * {@code java.lang.SecurityException}.
627 *
628 * @param logger a Logger object instance
629 * @param level a Level object instance indicating the degree of logging
630 * required
631 * @throws java.lang.SecurityException if a security manager exists and its
632 * {@code checkPermission} method denies calling {@code setLogger}
633 * @throws NullPointerException if the logger is null
634 * @see SecurityManager#checkPermission
635 * @see LoggingPermission
636 */
637 public static void setLogger(Logger logger, Level level) {
638 // singleton
639 SecurityManager sec = System.getSecurityManager();
640 if (sec != null) {
641 sec.checkPermission(SET_SYNCFACTORY_PERMISSION);
642 }
643
644 if(logger == null){
645 throw new NullPointerException("You must provide a Logger");
646 }
647 logger.setLevel(level);
648 rsLogger = logger;
649 }
650
651 /**
652 * Returns the logging object for applications to retrieve
653 * synchronization events posted by SyncProvider implementations.
654 * @return The {@code Logger} that has been specified for use by
655 * {@code SyncProvider} implementations
656 * @throws SyncFactoryException if no logging object has been set.
657 */
658 public static Logger getLogger() throws SyncFactoryException {
659
660 Logger result = rsLogger;
661 // only one logger per session
662 if (result == null) {
663 throw new SyncFactoryException("(SyncFactory) : No logger has been set");
664 }
665
666 return result;
667 }
668
669 /**
670 * Sets the initial JNDI context from which SyncProvider implementations
671 * can be retrieved from a JNDI namespace
672 * <p>
673 * This method checks to see that there is an {@code SQLPermission}
674 * object which grants the permission {@code setSyncFactory}
675 * before allowing the method to succeed. If a
676 * {@code SecurityManager} exists and its
677 * {@code checkPermission} method denies calling {@code setJNDIContext},
678 * this method throws a
679 * {@code java.lang.SecurityException}.
680 *
681 * @param ctx a valid JNDI context
682 * @throws SyncFactoryException if the supplied JNDI context is null
683 * @throws java.lang.SecurityException if a security manager exists and its
684 * {@code checkPermission} method denies calling {@code setJNDIContext}
685 * @see SecurityManager#checkPermission
686 */
687 public static synchronized void setJNDIContext(javax.naming.Context ctx)
688 throws SyncFactoryException {
689 SecurityManager sec = System.getSecurityManager();
690 if (sec != null) {
691 sec.checkPermission(SET_SYNCFACTORY_PERMISSION);
692 }
693 if (ctx == null) {
694 throw new SyncFactoryException("Invalid JNDI context supplied");
695 }
696 ic = ctx;
697 }
698
699 /**
700 * Controls JNDI context initialization.
701 *
702 * @throws SyncFactoryException if an error occurs parsing the JNDI context
703 */
704 private static synchronized void initJNDIContext() throws SyncFactoryException {
705
706 if ((ic != null) && (lazyJNDICtxRefresh == false)) {
707 try {
708 parseProperties(parseJNDIContext());
709 lazyJNDICtxRefresh = true; // touch JNDI namespace once.
710 } catch (NamingException e) {
711 e.printStackTrace();
712 throw new SyncFactoryException("SPI: NamingException: " + e.getExplanation());
713 } catch (Exception e) {
714 e.printStackTrace();
715 throw new SyncFactoryException("SPI: Exception: " + e.getMessage());
716 }
717 }
718 }
719 /**
720 * Internal switch indicating whether the JNDI namespace should be re-read.
721 */
722 private static boolean lazyJNDICtxRefresh = false;
723
724 /**
725 * Parses the set JNDI Context and passes bindings to the enumerateBindings
726 * method when complete.
727 */
728 private static Properties parseJNDIContext() throws NamingException {
729
730 NamingEnumeration<?> bindings = ic.listBindings("");
731 Properties properties = new Properties();
732
733 // Hunt one level below context for available SyncProvider objects
734 enumerateBindings(bindings, properties);
735
736 return properties;
737 }
738
739 /**
740 * Scans each binding on JNDI context and determines if any binding is an
741 * instance of SyncProvider, if so, add this to the registry and continue to
742 * scan the current context using a re-entrant call to this method until all
743 * bindings have been enumerated.
744 */
745 private static void enumerateBindings(NamingEnumeration<?> bindings,
746 Properties properties) throws NamingException {
747
748 boolean syncProviderObj = false; // move to parameters ?
749
750 try {
751 Binding bd = null;
752 Object elementObj = null;
753 String element = null;
754 while (bindings.hasMore()) {
755 bd = (Binding) bindings.next();
756 element = bd.getName();
757 elementObj = bd.getObject();
758
759 if (!(ic.lookup(element) instanceof Context)) {
760 // skip directories/sub-contexts
761 if (ic.lookup(element) instanceof SyncProvider) {
762 syncProviderObj = true;
763 }
764 }
765
766 if (syncProviderObj) {
767 SyncProvider sync = (SyncProvider) elementObj;
768 properties.put(SyncFactory.ROWSET_SYNC_PROVIDER,
769 sync.getProviderID());
770 syncProviderObj = false; // reset
771 }
772
773 }
774 } catch (javax.naming.NotContextException e) {
775 bindings.next();
776 // Re-entrant call into method
777 enumerateBindings(bindings, properties);
778 }
779 }
780
781 /**
782 * Lazy initialization Holder class used by {@code getSyncFactory}
783 */
784 private static class SyncFactoryHolder {
785 static final SyncFactory factory = new SyncFactory();
786 }
787 }
788
789 /**
790 * Internal class that defines the lazy reference construct for each registered
791 * SyncProvider implementation.
792 */
793 class ProviderImpl extends SyncProvider {
794
795 private String className = null;
796 private String vendorName = null;
797 private String ver = null;
798 private int index;
799
800 public void setClassname(String classname) {
801 className = classname;
802 }
803
804 public String getClassname() {
805 return className;
806 }
807
808 public void setVendor(String vendor) {
809 vendorName = vendor;
810 }
811
812 public String getVendor() {
813 return vendorName;
814 }
815
816 public void setVersion(String providerVer) {
817 ver = providerVer;
818 }
819
820 public String getVersion() {
821 return ver;
822 }
823
824 public void setIndex(int i) {
825 index = i;
826 }
827
828 public int getIndex() {
829 return index;
830 }
831
832 public int getDataSourceLock() throws SyncProviderException {
833
834 int dsLock = 0;
835 try {
836 dsLock = SyncFactory.getInstance(className).getDataSourceLock();
837 } catch (SyncFactoryException sfEx) {
838
839 throw new SyncProviderException(sfEx.getMessage());
840 }
841
842 return dsLock;
843 }
844
845 public int getProviderGrade() {
846
847 int grade = 0;
848
849 try {
850 grade = SyncFactory.getInstance(className).getProviderGrade();
851 } catch (SyncFactoryException sfEx) {
852 //
853 }
854
855 return grade;
856 }
857
858 public String getProviderID() {
859 return className;
860 }
861
862 /*
863 public javax.sql.RowSetInternal getRowSetInternal() {
864 try
865 {
866 return SyncFactory.getInstance(className).getRowSetInternal();
867 } catch(SyncFactoryException sfEx) {
868 //
869 }
870 }
871 */
872 public javax.sql.RowSetReader getRowSetReader() {
873
874 RowSetReader rsReader = null;
875
876 try {
877 rsReader = SyncFactory.getInstance(className).getRowSetReader();
878 } catch (SyncFactoryException sfEx) {
879 //
880 }
881
882 return rsReader;
883
884 }
885
886 public javax.sql.RowSetWriter getRowSetWriter() {
887
888 RowSetWriter rsWriter = null;
889 try {
890 rsWriter = SyncFactory.getInstance(className).getRowSetWriter();
891 } catch (SyncFactoryException sfEx) {
892 //
893 }
894
895 return rsWriter;
896 }
897
898 public void setDataSourceLock(int param)
899 throws SyncProviderException {
900
901 try {
902 SyncFactory.getInstance(className).setDataSourceLock(param);
903 } catch (SyncFactoryException sfEx) {
904
905 throw new SyncProviderException(sfEx.getMessage());
906 }
907 }
908
909 public int supportsUpdatableView() {
910
911 int view = 0;
912
913 try {
914 view = SyncFactory.getInstance(className).supportsUpdatableView();
915 } catch (SyncFactoryException sfEx) {
916 //
917 }
918
919 return view;
920 }
921 }