1 /*
2 * Copyright (c) 2003, 2012, 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
18 * 2 along with this work; if not, write to the Free Software Foundation,
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
22 * or visit www.oracle.com if you need additional information or have any
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 * <ul>
264 * <pre>
265 * SyncProvider p = new MySyncProvider();
266 * InitialContext ic = new InitialContext();
267 * ic.bind ("jdbc/rowset/MySyncProvider", p);
268 * </pre>
269 * </ul>
270 * Furthermore, an initial JNDI context should be set with the
271 * <code>SyncFactory</code> using the <code>setJNDIContext</code> method.
272 * The <code>SyncFactory</code> leverages this context to search for
273 * available <code>SyncProvider</code> objects bound to the JNDI
274 * context and its child nodes.
275 *
276 * @param providerID A <code>String</code> object with the unique ID of the
277 * synchronization provider being registered
278 * @throws SyncFactoryException if an attempt is made to supply an empty
279 * or null provider name
280 * @see #setJNDIContext
281 */
282 public static synchronized void registerProvider(String providerID)
283 throws SyncFactoryException {
284
285 ProviderImpl impl = new ProviderImpl();
286 impl.setClassname(providerID);
287 initMapIfNecessary();
288 implementations.put(providerID, impl);
289
290 }
291
292 /**
293 * Returns the <code>SyncFactory</code> singleton.
294 *
295 * @return the <code>SyncFactory</code> instance
296 */
297 public static SyncFactory getSyncFactory() {
298 /*
299 * Using Initialization on Demand Holder idiom as
300 * Effective Java 2nd Edition,ITEM 71, indicates it is more performant
301 * than the Double-Check Locking idiom.
302 */
303 return SyncFactoryHolder.factory;
304 }
305
306 /**
307 * Removes the designated currently registered synchronization provider from the
308 * Factory SPI register.
309 *
310 * @param providerID The unique-id of the synchronization provider
311 * @throws SyncFactoryException If an attempt is made to
312 * unregister a SyncProvider implementation that was not registered.
313 */
314 public static synchronized void unregisterProvider(String providerID)
315 throws SyncFactoryException {
316 initMapIfNecessary();
317 if (implementations.containsKey(providerID)) {
318 implementations.remove(providerID);
319 }
320 }
321 private static String colon = ":";
322 private static String strFileSep = "/";
323
324 private static synchronized void initMapIfNecessary() throws SyncFactoryException {
325
326 // Local implementation class names and keys from Properties
327 // file, translate names into Class objects using Class.forName
328 // and store mappings
329 Properties properties = new Properties();
330
331 if (implementations == null) {
332 implementations = new Hashtable<>();
333
334 try {
335
336 // check if user is supplying his Synchronisation Provider
337 // Implementation if not using Oracle's implementation.
338 // properties.load(new FileInputStream(ROWSET_PROPERTIES));
339
340 // The rowset.properties needs to be in jdk/jre/lib when
341 // integrated with jdk.
342 // else it should be picked from -D option from command line.
343
344 // -Drowset.properties will add to standard properties. Similar
345 // keys will over-write
346
347 /*
348 * Dependent on application
349 */
350 String strRowsetProperties = System.getProperty("rowset.properties");
351 if (strRowsetProperties != null) {
352 // Load user's implementation of SyncProvider
353 // here. -Drowset.properties=/abc/def/pqr.txt
354 ROWSET_PROPERTIES = strRowsetProperties;
355 try (FileInputStream fis = new FileInputStream(ROWSET_PROPERTIES)) {
356 properties.load(fis);
357 }
358 parseProperties(properties);
359 }
360
361 /*
362 * Always available
363 */
364 ROWSET_PROPERTIES = "javax" + strFileSep + "sql" +
365 strFileSep + "rowset" + strFileSep +
366 "rowset.properties";
367
368 ClassLoader cl = Thread.currentThread().getContextClassLoader();
369
370 try (InputStream stream =
371 (cl == null) ? ClassLoader.getSystemResourceAsStream(ROWSET_PROPERTIES)
372 : cl.getResourceAsStream(ROWSET_PROPERTIES)) {
373 if (stream == null) {
374 throw new SyncFactoryException(
375 "Resource " + ROWSET_PROPERTIES + " not found");
376 }
377 properties.load(stream);
378 }
379
380 parseProperties(properties);
381
382 // removed else, has properties should sum together
383
384 } catch (FileNotFoundException e) {
385 throw new SyncFactoryException("Cannot locate properties file: " + e);
386 } catch (IOException e) {
387 throw new SyncFactoryException("IOException: " + e);
388 }
389
390 /*
391 * Now deal with -Drowset.provider.classname
392 * load additional properties from -D command line
393 */
394 properties.clear();
395 String providerImpls = System.getProperty(ROWSET_SYNC_PROVIDER);
396
397 if (providerImpls != null) {
398 int i = 0;
399 if (providerImpls.indexOf(colon) > 0) {
400 StringTokenizer tokenizer = new StringTokenizer(providerImpls, colon);
401 while (tokenizer.hasMoreElements()) {
402 properties.put(ROWSET_SYNC_PROVIDER + "." + i, tokenizer.nextToken());
403 i++;
404 }
405 } else {
406 properties.put(ROWSET_SYNC_PROVIDER, providerImpls);
407 }
408 parseProperties(properties);
409 }
410 }
411 }
412
413 /**
414 * The internal debug switch.
415 */
416 private static boolean debug = false;
417 /**
418 * Internal registry count for the number of providers contained in the
419 * registry.
420 */
421 private static int providerImplIndex = 0;
422
423 /**
424 * Internal handler for all standard property parsing. Parses standard
425 * ROWSET properties and stores lazy references into the the internal registry.
426 */
427 private static void parseProperties(Properties p) {
428
429 ProviderImpl impl = null;
430 String key = null;
431 String[] propertyNames = null;
432
433 for (Enumeration<?> e = p.propertyNames(); e.hasMoreElements();) {
434
435 String str = (String) e.nextElement();
436
437 int w = str.length();
438
439 if (str.startsWith(SyncFactory.ROWSET_SYNC_PROVIDER)) {
440
441 impl = new ProviderImpl();
442 impl.setIndex(providerImplIndex++);
443
444 if (w == (SyncFactory.ROWSET_SYNC_PROVIDER).length()) {
445 // no property index has been set.
446 propertyNames = getPropertyNames(false);
447 } else {
448 // property index has been set.
449 propertyNames = getPropertyNames(true, str.substring(w - 1));
450 }
451
452 key = p.getProperty(propertyNames[0]);
453 impl.setClassname(key);
454 impl.setVendor(p.getProperty(propertyNames[1]));
455 impl.setVersion(p.getProperty(propertyNames[2]));
456 implementations.put(key, impl);
457 }
458 }
459 }
460
461 /**
462 * Used by the parseProperties methods to disassemble each property tuple.
463 */
464 private static String[] getPropertyNames(boolean append) {
465 return getPropertyNames(append, null);
466 }
467
468 /**
469 * Disassembles each property and its associated value. Also handles
470 * overloaded property names that contain indexes.
471 */
472 private static String[] getPropertyNames(boolean append,
473 String propertyIndex) {
474 String dot = ".";
475 String[] propertyNames =
476 new String[]{SyncFactory.ROWSET_SYNC_PROVIDER,
477 SyncFactory.ROWSET_SYNC_VENDOR,
478 SyncFactory.ROWSET_SYNC_PROVIDER_VERSION};
479 if (append) {
480 for (int i = 0; i < propertyNames.length; i++) {
481 propertyNames[i] = propertyNames[i] +
482 dot +
483 propertyIndex;
484 }
485 return propertyNames;
486 } else {
487 return propertyNames;
488 }
489 }
490
491 /**
492 * Internal debug method that outputs the registry contents.
493 */
494 private static void showImpl(ProviderImpl impl) {
495 System.out.println("Provider implementation:");
496 System.out.println("Classname: " + impl.getClassname());
497 System.out.println("Vendor: " + impl.getVendor());
498 System.out.println("Version: " + impl.getVersion());
499 System.out.println("Impl index: " + impl.getIndex());
500 }
501
502 /**
503 * Returns the <code>SyncProvider</code> instance identified by <i>providerID</i>.
504 *
505 * @param providerID the unique identifier of the provider
506 * @return a <code>SyncProvider</code> implementation
507 * @throws SyncFactoryException If the SyncProvider cannot be found,
508 * the providerID is {@code null}, or
509 * some error was encountered when trying to invoke this provider.
510 */
511 public static SyncProvider getInstance(String providerID)
512 throws SyncFactoryException {
513
514 if(providerID == null) {
515 throw new SyncFactoryException("The providerID cannot be null");
516 }
517
518 initMapIfNecessary(); // populate HashTable
519 initJNDIContext(); // check JNDI context for any additional bindings
520
521 ProviderImpl impl = (ProviderImpl) implementations.get(providerID);
522
523 if (impl == null) {
524 // Requested SyncProvider is unavailable. Return default provider.
525 return new com.sun.rowset.providers.RIOptimisticProvider();
526 }
527
528 // Attempt to invoke classname from registered SyncProvider list
529 Class<?> c = null;
530 try {
531 ClassLoader cl = Thread.currentThread().getContextClassLoader();
532
533 /**
534 * The SyncProvider implementation of the user will be in
535 * the classpath. We need to find the ClassLoader which loads
536 * this SyncFactory and try to laod the SyncProvider class from
537 * there.
538 **/
539 c = Class.forName(providerID, true, cl);
540
541 if (c != null) {
542 return (SyncProvider) c.newInstance();
543 } else {
544 return new com.sun.rowset.providers.RIOptimisticProvider();
545 }
546
547 } catch (IllegalAccessException e) {
548 throw new SyncFactoryException("IllegalAccessException: " + e.getMessage());
549 } catch (InstantiationException e) {
550 throw new SyncFactoryException("InstantiationException: " + e.getMessage());
551 } catch (ClassNotFoundException e) {
552 throw new SyncFactoryException("ClassNotFoundException: " + e.getMessage());
553 }
554 }
555
556 /**
557 * Returns an Enumeration of currently registered synchronization
558 * providers. A <code>RowSet</code> implementation may use any provider in
559 * the enumeration as its <code>SyncProvider</code> object.
560 * <p>
561 * At a minimum, the reference synchronization provider allowing
562 * RowSet content data to be stored using a JDBC driver should be
563 * possible.
564 *
565 * @return Enumeration A enumeration of available synchronization
566 * providers that are registered with this Factory
567 */
568 public static Enumeration<SyncProvider> getRegisteredProviders()
569 throws SyncFactoryException {
570 initMapIfNecessary();
571 // return a collection of classnames
572 // of type SyncProvider
573 return implementations.elements();
574 }
575
576 /**
577 * Sets the logging object to be used by the <code>SyncProvider</code>
578 * implementation provided by the <code>SyncFactory</code>. All
579 * <code>SyncProvider</code> implementations can log their events to
580 * this object and the application can retrieve a handle to this
581 * object using the <code>getLogger</code> method.
582 * <p>
583 * This method checks to see that there is an {@code SQLPermission}
584 * object which grants the permission {@code setSyncFactory}
585 * before allowing the method to succeed. If a
586 * {@code SecurityManager} exists and its
587 * {@code checkPermission} method denies calling {@code setLogger},
588 * this method throws a
589 * {@code java.lang.SecurityException}.
590 *
591 * @param logger A Logger object instance
592 * @throws java.lang.SecurityException if a security manager exists and its
593 * {@code checkPermission} method denies calling {@code setLogger}
594 * @throws NullPointerException if the logger is null
595 * @see SecurityManager#checkPermission
596 */
597 public static void setLogger(Logger logger) {
598
599 SecurityManager sec = System.getSecurityManager();
600 if (sec != null) {
601 sec.checkPermission(SET_SYNCFACTORY_PERMISSION);
602 }
603
604 if(logger == null){
605 throw new NullPointerException("You must provide a Logger");
606 }
607 rsLogger = logger;
608 }
609
610 /**
611 * Sets the logging object that is used by <code>SyncProvider</code>
612 * implementations provided by the <code>SyncFactory</code> SPI. All
613 * <code>SyncProvider</code> implementations can log their events
614 * to this object and the application can retrieve a handle to this
615 * object using the <code>getLogger</code> method.
616 * <p>
617 * This method checks to see that there is an {@code SQLPermission}
618 * object which grants the permission {@code setSyncFactory}
619 * before allowing the method to succeed. If a
620 * {@code SecurityManager} exists and its
621 * {@code checkPermission} method denies calling {@code setLogger},
622 * this method throws a
623 * {@code java.lang.SecurityException}.
624 *
625 * @param logger a Logger object instance
626 * @param level a Level object instance indicating the degree of logging
627 * required
628 * @throws java.lang.SecurityException if a security manager exists and its
629 * {@code checkPermission} method denies calling {@code setLogger}
630 * @throws java.util.logging.LoggingPermission if a security manager exists and its
631 * {@code checkPermission} method denies calling {@code setLevel}
632 * @throws NullPointerException if the logger is null
633 * @see SecurityManager#checkPermission
634 * @see LoggingPermission
635 */
636 public static void setLogger(Logger logger, Level level) {
637 // singleton
638 SecurityManager sec = System.getSecurityManager();
639 if (sec != null) {
640 sec.checkPermission(SET_SYNCFACTORY_PERMISSION);
641 }
642
643 if(logger == null){
644 throw new NullPointerException("You must provide a Logger");
645 }
646 logger.setLevel(level);
647 rsLogger = logger;
648 }
649
650 /**
651 * Returns the logging object for applications to retrieve
652 * synchronization events posted by SyncProvider implementations.
653 *
654 * @throws SyncFactoryException if no logging object has been set.
655 */
656 public static Logger getLogger() throws SyncFactoryException {
657
658 Logger result = rsLogger;
659 // only one logger per session
660 if (result == null) {
661 throw new SyncFactoryException("(SyncFactory) : No logger has been set");
662 }
663
664 return result;
665 }
666
667 /**
668 * Sets the initial JNDI context from which SyncProvider implementations
669 * can be retrieved from a JNDI namespace
670 * <p>
671 * This method checks to see that there is an {@code SQLPermission}
672 * object which grants the permission {@code setSyncFactory}
673 * before allowing the method to succeed. If a
674 * {@code SecurityManager} exists and its
675 * {@code checkPermission} method denies calling {@code setJNDIContext},
676 * this method throws a
677 * {@code java.lang.SecurityException}.
678 *
679 * @param ctx a valid JNDI context
680 * @throws SyncFactoryException if the supplied JNDI context is null
681 * @throws java.lang.SecurityException if a security manager exists and its
682 * {@code checkPermission} method denies calling {@code setJNDIContext}
683 * @see SecurityManager#checkPermission
684 */
685 public static synchronized void setJNDIContext(javax.naming.Context ctx)
686 throws SyncFactoryException {
687 SecurityManager sec = System.getSecurityManager();
688 if (sec != null) {
689 sec.checkPermission(SET_SYNCFACTORY_PERMISSION);
690 }
691 if (ctx == null) {
692 throw new SyncFactoryException("Invalid JNDI context supplied");
693 }
694 ic = ctx;
695 }
696
697 /**
698 * Controls JNDI context initialization.
699 *
700 * @throws SyncFactoryException if an error occurs parsing the JNDI context
701 */
702 private static synchronized void initJNDIContext() throws SyncFactoryException {
703
704 if ((ic != null) && (lazyJNDICtxRefresh == false)) {
705 try {
706 parseProperties(parseJNDIContext());
707 lazyJNDICtxRefresh = true; // touch JNDI namespace once.
708 } catch (NamingException e) {
709 e.printStackTrace();
710 throw new SyncFactoryException("SPI: NamingException: " + e.getExplanation());
711 } catch (Exception e) {
712 e.printStackTrace();
713 throw new SyncFactoryException("SPI: Exception: " + e.getMessage());
714 }
715 }
716 }
717 /**
718 * Internal switch indicating whether the JNDI namespace should be re-read.
719 */
720 private static boolean lazyJNDICtxRefresh = false;
721
722 /**
723 * Parses the set JNDI Context and passes bindings to the enumerateBindings
724 * method when complete.
725 */
726 private static Properties parseJNDIContext() throws NamingException {
727
728 NamingEnumeration<?> bindings = ic.listBindings("");
729 Properties properties = new Properties();
730
731 // Hunt one level below context for available SyncProvider objects
732 enumerateBindings(bindings, properties);
733
734 return properties;
735 }
736
737 /**
738 * Scans each binding on JNDI context and determines if any binding is an
739 * instance of SyncProvider, if so, add this to the registry and continue to
740 * scan the current context using a re-entrant call to this method until all
741 * bindings have been enumerated.
742 */
743 private static void enumerateBindings(NamingEnumeration<?> bindings,
744 Properties properties) throws NamingException {
745
746 boolean syncProviderObj = false; // move to parameters ?
747
748 try {
749 Binding bd = null;
750 Object elementObj = null;
751 String element = null;
752 while (bindings.hasMore()) {
753 bd = (Binding) bindings.next();
754 element = bd.getName();
755 elementObj = bd.getObject();
756
757 if (!(ic.lookup(element) instanceof Context)) {
758 // skip directories/sub-contexts
759 if (ic.lookup(element) instanceof SyncProvider) {
760 syncProviderObj = true;
761 }
762 }
763
764 if (syncProviderObj) {
765 SyncProvider sync = (SyncProvider) elementObj;
766 properties.put(SyncFactory.ROWSET_SYNC_PROVIDER,
767 sync.getProviderID());
768 syncProviderObj = false; // reset
769 }
770
771 }
772 } catch (javax.naming.NotContextException e) {
773 bindings.next();
774 // Re-entrant call into method
775 enumerateBindings(bindings, properties);
776 }
777 }
778
779 /**
780 * Lazy initialization Holder class used by {@code getSyncFactory}
781 */
782 private static class SyncFactoryHolder {
783 static final SyncFactory factory = new SyncFactory();
784 }
785 }
786
787 /**
788 * Internal class that defines the lazy reference construct for each registered
789 * SyncProvider implementation.
790 */
791 class ProviderImpl extends SyncProvider {
792
793 private String className = null;
794 private String vendorName = null;
795 private String ver = null;
796 private int index;
797
798 public void setClassname(String classname) {
799 className = classname;
800 }
801
802 public String getClassname() {
803 return className;
804 }
805
806 public void setVendor(String vendor) {
807 vendorName = vendor;
808 }
809
810 public String getVendor() {
811 return vendorName;
812 }
813
814 public void setVersion(String providerVer) {
815 ver = providerVer;
816 }
817
818 public String getVersion() {
819 return ver;
820 }
821
822 public void setIndex(int i) {
823 index = i;
824 }
825
826 public int getIndex() {
827 return index;
828 }
829
830 public int getDataSourceLock() throws SyncProviderException {
831
832 int dsLock = 0;
833 try {
834 dsLock = SyncFactory.getInstance(className).getDataSourceLock();
835 } catch (SyncFactoryException sfEx) {
836
837 throw new SyncProviderException(sfEx.getMessage());
838 }
839
840 return dsLock;
841 }
842
843 public int getProviderGrade() {
844
845 int grade = 0;
846
847 try {
848 grade = SyncFactory.getInstance(className).getProviderGrade();
849 } catch (SyncFactoryException sfEx) {
850 //
851 }
852
853 return grade;
854 }
855
856 public String getProviderID() {
857 return className;
858 }
859
860 /*
861 public javax.sql.RowSetInternal getRowSetInternal() {
862 try
863 {
864 return SyncFactory.getInstance(className).getRowSetInternal();
865 } catch(SyncFactoryException sfEx) {
866 //
867 }
868 }
869 */
870 public javax.sql.RowSetReader getRowSetReader() {
871
872 RowSetReader rsReader = null;
873
874 try {
875 rsReader = SyncFactory.getInstance(className).getRowSetReader();
876 } catch (SyncFactoryException sfEx) {
877 //
878 }
879
880 return rsReader;
881
882 }
883
884 public javax.sql.RowSetWriter getRowSetWriter() {
885
886 RowSetWriter rsWriter = null;
887 try {
888 rsWriter = SyncFactory.getInstance(className).getRowSetWriter();
889 } catch (SyncFactoryException sfEx) {
890 //
891 }
892
893 return rsWriter;
894 }
895
896 public void setDataSourceLock(int param)
897 throws SyncProviderException {
898
899 try {
900 SyncFactory.getInstance(className).setDataSourceLock(param);
901 } catch (SyncFactoryException sfEx) {
902
903 throw new SyncProviderException(sfEx.getMessage());
904 }
905 }
906
907 public int supportsUpdatableView() {
908
909 int view = 0;
910
911 try {
912 view = SyncFactory.getInstance(className).supportsUpdatableView();
913 } catch (SyncFactoryException sfEx) {
914 //
915 }
916
917 return view;
918 }
919 }