J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 1999-2001 Sun Microsystems, Inc. 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. Sun designates this |
| 8 | * particular file as subject to the "Classpath" exception as provided |
| 9 | * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
| 22 | * CA 95054 USA or visit www.sun.com if you need additional information or |
| 23 | * have any questions. |
| 24 | */ |
| 25 | |
| 26 | package com.sun.naming.internal; |
| 27 | |
| 28 | import java.applet.Applet; |
| 29 | import java.io.InputStream; |
| 30 | import java.io.IOException; |
| 31 | import java.net.URL; |
| 32 | import java.lang.ref.WeakReference; |
| 33 | import java.util.Enumeration; |
| 34 | import java.util.HashMap; |
| 35 | import java.util.Hashtable; |
| 36 | import java.util.Map; |
| 37 | import java.util.Properties; |
| 38 | import java.util.StringTokenizer; |
| 39 | import java.util.List; |
| 40 | import java.util.ArrayList; |
| 41 | import java.util.WeakHashMap; |
| 42 | |
| 43 | import javax.naming.*; |
| 44 | |
| 45 | /** |
| 46 | * The ResourceManager class facilitates the reading of JNDI resource files. |
| 47 | * |
| 48 | * @author Rosanna Lee |
| 49 | * @author Scott Seligman |
| 50 | */ |
| 51 | |
| 52 | public final class ResourceManager { |
| 53 | |
| 54 | /* |
| 55 | * Name of provider resource files (without the package-name prefix.) |
| 56 | */ |
| 57 | private static final String PROVIDER_RESOURCE_FILE_NAME = |
| 58 | "jndiprovider.properties"; |
| 59 | |
| 60 | /* |
| 61 | * Name of application resource files. |
| 62 | */ |
| 63 | private static final String APP_RESOURCE_FILE_NAME = "jndi.properties"; |
| 64 | |
| 65 | /* |
| 66 | * Name of properties file in <java.home>/lib. |
| 67 | */ |
| 68 | private static final String JRELIB_PROPERTY_FILE_NAME = "jndi.properties"; |
| 69 | |
| 70 | /* |
| 71 | * The standard JNDI properties that specify colon-separated lists. |
| 72 | */ |
| 73 | private static final String[] listProperties = { |
| 74 | Context.OBJECT_FACTORIES, |
| 75 | Context.URL_PKG_PREFIXES, |
| 76 | Context.STATE_FACTORIES, |
| 77 | // The following shouldn't create a runtime dependence on ldap package. |
| 78 | javax.naming.ldap.LdapContext.CONTROL_FACTORIES |
| 79 | }; |
| 80 | |
| 81 | private static final VersionHelper helper = |
| 82 | VersionHelper.getVersionHelper(); |
| 83 | |
| 84 | /* |
| 85 | * A cache of the properties that have been constructed by |
| 86 | * the ResourceManager. A Hashtable from a provider resource |
| 87 | * file is keyed on a class in the resource file's package. |
| 88 | * One from application resource files is keyed on the thread's |
| 89 | * context class loader. |
| 90 | */ |
| 91 | private static final WeakHashMap propertiesCache = new WeakHashMap(11); |
| 92 | |
| 93 | /* |
| 94 | * A cache of factory objects (ObjectFactory, StateFactory, ControlFactory). |
| 95 | * |
| 96 | * A two-level cache keyed first on context class loader and then |
| 97 | * on propValue. Value is a list of class or factory objects, |
| 98 | * weakly referenced so as not to prevent GC of the class loader. |
| 99 | * Used in getFactories(). |
| 100 | */ |
| 101 | private static final WeakHashMap factoryCache = new WeakHashMap(11); |
| 102 | |
| 103 | /* |
| 104 | * A cache of URL factory objects (ObjectFactory). |
| 105 | * |
| 106 | * A two-level cache keyed first on context class loader and then |
| 107 | * on classSuffix+propValue. Value is the factory itself (weakly |
| 108 | * referenced so as not to prevent GC of the class loader) or |
| 109 | * NO_FACTORY if a previous search revealed no factory. Used in |
| 110 | * getFactory(). |
| 111 | */ |
| 112 | private static final WeakHashMap urlFactoryCache = new WeakHashMap(11); |
| 113 | private static final WeakReference NO_FACTORY = new WeakReference(null); |
| 114 | |
| 115 | |
| 116 | // There should be no instances of this class. |
| 117 | private ResourceManager() { |
| 118 | } |
| 119 | |
| 120 | |
| 121 | // ---------- Public methods ---------- |
| 122 | |
| 123 | /* |
| 124 | * Given the environment parameter passed to the initial context |
| 125 | * constructor, returns the full environment for that initial |
| 126 | * context (never null). This is based on the environment |
| 127 | * parameter, the applet parameters (where appropriate), the |
| 128 | * system properties, and all application resource files. |
| 129 | * |
| 130 | * <p> This method will modify <tt>env</tt> and save |
| 131 | * a reference to it. The caller may no longer modify it. |
| 132 | * |
| 133 | * @param env environment passed to initial context constructor. |
| 134 | * Null indicates an empty environment. |
| 135 | * |
| 136 | * @throws NamingException if an error occurs while reading a |
| 137 | * resource file |
| 138 | */ |
| 139 | public static Hashtable getInitialEnvironment(Hashtable env) |
| 140 | throws NamingException |
| 141 | { |
| 142 | String[] props = VersionHelper.PROPS; // system/applet properties |
| 143 | if (env == null) { |
| 144 | env = new Hashtable(11); |
| 145 | } |
| 146 | Applet applet = (Applet)env.get(Context.APPLET); |
| 147 | |
| 148 | // Merge property values from env param, applet params, and system |
| 149 | // properties. The first value wins: there's no concatenation of |
| 150 | // colon-separated lists. |
| 151 | // Read system properties by first trying System.getProperties(), |
| 152 | // and then trying System.getProperty() if that fails. The former |
| 153 | // is more efficient due to fewer permission checks. |
| 154 | // |
| 155 | String[] jndiSysProps = helper.getJndiProperties(); |
| 156 | for (int i = 0; i < props.length; i++) { |
| 157 | Object val = env.get(props[i]); |
| 158 | if (val == null) { |
| 159 | if (applet != null) { |
| 160 | val = applet.getParameter(props[i]); |
| 161 | } |
| 162 | if (val == null) { |
| 163 | // Read system property. |
| 164 | val = (jndiSysProps != null) |
| 165 | ? jndiSysProps[i] |
| 166 | : helper.getJndiProperty(i); |
| 167 | } |
| 168 | if (val != null) { |
| 169 | env.put(props[i], val); |
| 170 | } |
| 171 | } |
| 172 | } |
| 173 | |
| 174 | // Merge the above with the values read from all application |
| 175 | // resource files. Colon-separated lists are concatenated. |
| 176 | mergeTables(env, getApplicationResources()); |
| 177 | return env; |
| 178 | } |
| 179 | |
| 180 | /** |
| 181 | * Retrieves the property from the environment, or from the provider |
| 182 | * resource file associated with the given context. The environment |
| 183 | * may in turn contain values that come from applet parameters, |
| 184 | * system properties, or application resource files. |
| 185 | * |
| 186 | * If <tt>concat</tt> is true and both the environment and the provider |
| 187 | * resource file contain the property, the two values are concatenated |
| 188 | * (with a ':' separator). |
| 189 | * |
| 190 | * Returns null if no value is found. |
| 191 | * |
| 192 | * @param propName The non-null property name |
| 193 | * @param env The possibly null environment properties |
| 194 | * @param ctx The possibly null context |
| 195 | * @param concat True if multiple values should be concatenated |
| 196 | * @return the property value, or null is there is none. |
| 197 | * @throws NamingException if an error occurs while reading the provider |
| 198 | * resource file. |
| 199 | */ |
| 200 | public static String getProperty(String propName, Hashtable env, |
| 201 | Context ctx, boolean concat) |
| 202 | throws NamingException { |
| 203 | |
| 204 | String val1 = (env != null) ? (String)env.get(propName) : null; |
| 205 | if ((ctx == null) || |
| 206 | ((val1 != null) && !concat)) { |
| 207 | return val1; |
| 208 | } |
| 209 | String val2 = (String)getProviderResource(ctx).get(propName); |
| 210 | if (val1 == null) { |
| 211 | return val2; |
| 212 | } else if ((val2 == null) || !concat) { |
| 213 | return val1; |
| 214 | } else { |
| 215 | return (val1 + ":" + val2); |
| 216 | } |
| 217 | } |
| 218 | |
| 219 | /** |
| 220 | * Retrieves an enumeration of factory classes/object specified by a |
| 221 | * property. |
| 222 | * |
| 223 | * The property is gotten from the environment and the provider |
| 224 | * resource file associated with the given context and concantenated. |
| 225 | * See getProperty(). The resulting property value is a list of class names. |
| 226 | *<p> |
| 227 | * This method then loads each class using the current thread's context |
| 228 | * class loader and keeps them in a list. Any class that cannot be loaded |
| 229 | * is ignored. The resulting list is then cached in a two-level |
| 230 | * hash table, keyed first by the context class loader and then by |
| 231 | * the property's value. |
| 232 | * The next time threads of the same context class loader call this |
| 233 | * method, they can use the cached list. |
| 234 | *<p> |
| 235 | * After obtaining the list either from the cache or by creating one from |
| 236 | * the property value, this method then creates and returns a |
| 237 | * FactoryEnumeration using the list. As the FactoryEnumeration is |
| 238 | * traversed, the cached Class object in the list is instantiated and |
| 239 | * replaced by an instance of the factory object itself. Both class |
| 240 | * objects and factories are wrapped in weak references so as not to |
| 241 | * prevent GC of the class loader. |
| 242 | *<p> |
| 243 | * Note that multiple threads can be accessing the same cached list |
| 244 | * via FactoryEnumeration, which locks the list during each next(). |
| 245 | * The size of the list will not change, |
| 246 | * but a cached Class object might be replaced by an instantiated factory |
| 247 | * object. |
| 248 | * |
| 249 | * @param propName The non-null property name |
| 250 | * @param env The possibly null environment properties |
| 251 | * @param ctx The possibly null context |
| 252 | * @return An enumeration of factory classes/objects; null if none. |
| 253 | * @exception NamingException If encounter problem while reading the provider |
| 254 | * property file. |
| 255 | * @see javax.naming.spi.NamingManager#getObjectInstance |
| 256 | * @see javax.naming.spi.NamingManager#getStateToBind |
| 257 | * @see javax.naming.spi.DirectoryManager#getObjectInstance |
| 258 | * @see javax.naming.spi.DirectoryManager#getStateToBind |
| 259 | * @see javax.naming.ldap.ControlFactory#getControlInstance |
| 260 | */ |
| 261 | public static FactoryEnumeration getFactories(String propName, Hashtable env, |
| 262 | Context ctx) throws NamingException { |
| 263 | |
| 264 | String facProp = getProperty(propName, env, ctx, true); |
| 265 | if (facProp == null) |
| 266 | return null; // no classes specified; return null |
| 267 | |
| 268 | // Cache is based on context class loader and property val |
| 269 | ClassLoader loader = helper.getContextClassLoader(); |
| 270 | |
| 271 | Map perLoaderCache = null; |
| 272 | synchronized (factoryCache) { |
| 273 | perLoaderCache = (Map) factoryCache.get(loader); |
| 274 | if (perLoaderCache == null) { |
| 275 | perLoaderCache = new HashMap(11); |
| 276 | factoryCache.put(loader, perLoaderCache); |
| 277 | } |
| 278 | } |
| 279 | |
| 280 | synchronized (perLoaderCache) { |
| 281 | List factories = (List) perLoaderCache.get(facProp); |
| 282 | if (factories != null) { |
| 283 | // Cached list |
| 284 | return factories.size() == 0 ? null |
| 285 | : new FactoryEnumeration(factories, loader); |
| 286 | } else { |
| 287 | // Populate list with classes named in facProp; skipping |
| 288 | // those that we cannot load |
| 289 | StringTokenizer parser = new StringTokenizer(facProp, ":"); |
| 290 | factories = new ArrayList(5); |
| 291 | while (parser.hasMoreTokens()) { |
| 292 | try { |
| 293 | // System.out.println("loading"); |
| 294 | String className = parser.nextToken(); |
| 295 | Class c = helper.loadClass(className, loader); |
| 296 | factories.add(new NamedWeakReference(c, className)); |
| 297 | } catch (Exception e) { |
| 298 | // ignore ClassNotFoundException, IllegalArgumentException |
| 299 | } |
| 300 | } |
| 301 | // System.out.println("adding to cache: " + factories); |
| 302 | perLoaderCache.put(facProp, factories); |
| 303 | return new FactoryEnumeration(factories, loader); |
| 304 | } |
| 305 | } |
| 306 | } |
| 307 | |
| 308 | /** |
| 309 | * Retrieves a factory from a list of packages specified in a |
| 310 | * property. |
| 311 | * |
| 312 | * The property is gotten from the environment and the provider |
| 313 | * resource file associated with the given context and concatenated. |
| 314 | * classSuffix is added to the end of this list. |
| 315 | * See getProperty(). The resulting property value is a list of package |
| 316 | * prefixes. |
| 317 | *<p> |
| 318 | * This method then constructs a list of class names by concatenating |
| 319 | * each package prefix with classSuffix and attempts to load and |
| 320 | * instantiate the class until one succeeds. |
| 321 | * Any class that cannot be loaded is ignored. |
| 322 | * The resulting object is then cached in a two-level hash table, |
| 323 | * keyed first by the context class loader and then by the property's |
| 324 | * value and classSuffix. |
| 325 | * The next time threads of the same context class loader call this |
| 326 | * method, they use the cached factory. |
| 327 | * If no factory can be loaded, NO_FACTORY is recorded in the table |
| 328 | * so that next time it'll return quickly. |
| 329 | * |
| 330 | * @param propName The non-null property name |
| 331 | * @param env The possibly null environment properties |
| 332 | * @param ctx The possibly null context |
| 333 | * @param classSuffix The non-null class name |
| 334 | * (e.g. ".ldap.ldapURLContextFactory). |
| 335 | * @param defaultPkgPrefix The non-null default package prefix. |
| 336 | * (e.g., "com.sun.jndi.url"). |
| 337 | * @return An factory object; null if none. |
| 338 | * @exception NamingException If encounter problem while reading the provider |
| 339 | * property file, or problem instantiating the factory. |
| 340 | * |
| 341 | * @see javax.naming.spi.NamingManager#getURLContext |
| 342 | * @see javax.naming.spi.NamingManager#getURLObject |
| 343 | */ |
| 344 | public static Object getFactory(String propName, Hashtable env, Context ctx, |
| 345 | String classSuffix, String defaultPkgPrefix) throws NamingException { |
| 346 | |
| 347 | // Merge property with provider property and supplied default |
| 348 | String facProp = getProperty(propName, env, ctx, true); |
| 349 | if (facProp != null) |
| 350 | facProp += (":" + defaultPkgPrefix); |
| 351 | else |
| 352 | facProp = defaultPkgPrefix; |
| 353 | |
| 354 | // Cache factory based on context class loader, class name, and |
| 355 | // property val |
| 356 | ClassLoader loader = helper.getContextClassLoader(); |
| 357 | String key = classSuffix + " " + facProp; |
| 358 | |
| 359 | Map perLoaderCache = null; |
| 360 | synchronized (urlFactoryCache) { |
| 361 | perLoaderCache = (Map) urlFactoryCache.get(loader); |
| 362 | if (perLoaderCache == null) { |
| 363 | perLoaderCache = new HashMap(11); |
| 364 | urlFactoryCache.put(loader, perLoaderCache); |
| 365 | } |
| 366 | } |
| 367 | |
| 368 | synchronized (perLoaderCache) { |
| 369 | Object factory = null; |
| 370 | |
| 371 | WeakReference factoryRef = (WeakReference) perLoaderCache.get(key); |
| 372 | if (factoryRef == NO_FACTORY) { |
| 373 | return null; |
| 374 | } else if (factoryRef != null) { |
| 375 | factory = factoryRef.get(); |
| 376 | if (factory != null) { // check if weak ref has been cleared |
| 377 | return factory; |
| 378 | } |
| 379 | } |
| 380 | |
| 381 | // Not cached; find first factory and cache |
| 382 | StringTokenizer parser = new StringTokenizer(facProp, ":"); |
| 383 | String className; |
| 384 | while (factory == null && parser.hasMoreTokens()) { |
| 385 | className = parser.nextToken() + classSuffix; |
| 386 | try { |
| 387 | // System.out.println("loading " + className); |
| 388 | factory = helper.loadClass(className, loader).newInstance(); |
| 389 | } catch (InstantiationException e) { |
| 390 | NamingException ne = |
| 391 | new NamingException("Cannot instantiate " + className); |
| 392 | ne.setRootCause(e); |
| 393 | throw ne; |
| 394 | } catch (IllegalAccessException e) { |
| 395 | NamingException ne = |
| 396 | new NamingException("Cannot access " + className); |
| 397 | ne.setRootCause(e); |
| 398 | throw ne; |
| 399 | } catch (Exception e) { |
| 400 | // ignore ClassNotFoundException, IllegalArgumentException, |
| 401 | // etc. |
| 402 | } |
| 403 | } |
| 404 | |
| 405 | // Cache it. |
| 406 | perLoaderCache.put(key, (factory != null) |
| 407 | ? new WeakReference(factory) |
| 408 | : NO_FACTORY); |
| 409 | return factory; |
| 410 | } |
| 411 | } |
| 412 | |
| 413 | |
| 414 | // ---------- Private methods ---------- |
| 415 | |
| 416 | /* |
| 417 | * Returns the properties contained in the provider resource file |
| 418 | * of an object's package. Returns an empty hash table if the |
| 419 | * object is null or the resource file cannot be found. The |
| 420 | * results are cached. |
| 421 | * |
| 422 | * @throws NamingException if an error occurs while reading the file. |
| 423 | */ |
| 424 | private static Hashtable getProviderResource(Object obj) |
| 425 | throws NamingException |
| 426 | { |
| 427 | if (obj == null) { |
| 428 | return (new Hashtable(1)); |
| 429 | } |
| 430 | synchronized (propertiesCache) { |
| 431 | Class c = obj.getClass(); |
| 432 | |
| 433 | Hashtable props = (Hashtable)propertiesCache.get(c); |
| 434 | if (props != null) { |
| 435 | return props; |
| 436 | } |
| 437 | props = new Properties(); |
| 438 | |
| 439 | InputStream istream = |
| 440 | helper.getResourceAsStream(c, PROVIDER_RESOURCE_FILE_NAME); |
| 441 | |
| 442 | if (istream != null) { |
| 443 | try { |
| 444 | ((Properties)props).load(istream); |
| 445 | } catch (IOException e) { |
| 446 | NamingException ne = new ConfigurationException( |
| 447 | "Error reading provider resource file for " + c); |
| 448 | ne.setRootCause(e); |
| 449 | throw ne; |
| 450 | } |
| 451 | } |
| 452 | propertiesCache.put(c, props); |
| 453 | return props; |
| 454 | } |
| 455 | } |
| 456 | |
| 457 | |
| 458 | /* |
| 459 | * Returns the Hashtable (never null) that results from merging |
| 460 | * all application resource files available to this thread's |
| 461 | * context class loader. The properties file in <java.home>/lib |
| 462 | * is also merged in. The results are cached. |
| 463 | * |
| 464 | * SECURITY NOTES: |
| 465 | * 1. JNDI needs permission to read the application resource files. |
| 466 | * 2. Any class will be able to use JNDI to view the contents of |
| 467 | * the application resource files in its own classpath. Give |
| 468 | * careful consideration to this before storing sensitive |
| 469 | * information there. |
| 470 | * |
| 471 | * @throws NamingException if an error occurs while reading a resource |
| 472 | * file. |
| 473 | */ |
| 474 | private static Hashtable getApplicationResources() throws NamingException { |
| 475 | |
| 476 | ClassLoader cl = helper.getContextClassLoader(); |
| 477 | |
| 478 | synchronized (propertiesCache) { |
| 479 | Hashtable result = (Hashtable)propertiesCache.get(cl); |
| 480 | if (result != null) { |
| 481 | return result; |
| 482 | } |
| 483 | |
| 484 | try { |
| 485 | NamingEnumeration resources = |
| 486 | helper.getResources(cl, APP_RESOURCE_FILE_NAME); |
| 487 | while (resources.hasMore()) { |
| 488 | Properties props = new Properties(); |
| 489 | props.load((InputStream)resources.next()); |
| 490 | |
| 491 | if (result == null) { |
| 492 | result = props; |
| 493 | } else { |
| 494 | mergeTables(result, props); |
| 495 | } |
| 496 | } |
| 497 | |
| 498 | // Merge in properties from file in <java.home>/lib. |
| 499 | InputStream istream = |
| 500 | helper.getJavaHomeLibStream(JRELIB_PROPERTY_FILE_NAME); |
| 501 | if (istream != null) { |
| 502 | Properties props = new Properties(); |
| 503 | props.load(istream); |
| 504 | |
| 505 | if (result == null) { |
| 506 | result = props; |
| 507 | } else { |
| 508 | mergeTables(result, props); |
| 509 | } |
| 510 | } |
| 511 | |
| 512 | } catch (IOException e) { |
| 513 | NamingException ne = new ConfigurationException( |
| 514 | "Error reading application resource file"); |
| 515 | ne.setRootCause(e); |
| 516 | throw ne; |
| 517 | } |
| 518 | if (result == null) { |
| 519 | result = new Hashtable(11); |
| 520 | } |
| 521 | propertiesCache.put(cl, result); |
| 522 | return result; |
| 523 | } |
| 524 | } |
| 525 | |
| 526 | /* |
| 527 | * Merge the properties from one hash table into another. Each |
| 528 | * property in props2 that is not in props1 is added to props1. |
| 529 | * For each property in both hash tables that is one of the |
| 530 | * standard JNDI properties that specify colon-separated lists, |
| 531 | * the values are concatenated and stored in props1. |
| 532 | */ |
| 533 | private static void mergeTables(Hashtable props1, Hashtable props2) { |
| 534 | Enumeration keys = props2.keys(); |
| 535 | |
| 536 | while (keys.hasMoreElements()) { |
| 537 | String prop = (String)keys.nextElement(); |
| 538 | Object val1 = props1.get(prop); |
| 539 | if (val1 == null) { |
| 540 | props1.put(prop, props2.get(prop)); |
| 541 | } else if (isListProperty(prop)) { |
| 542 | String val2 = (String)props2.get(prop); |
| 543 | props1.put(prop, ((String)val1) + ":" + val2); |
| 544 | } |
| 545 | } |
| 546 | } |
| 547 | |
| 548 | /* |
| 549 | * Is a property one of the standard JNDI properties that specify |
| 550 | * colon-separated lists? |
| 551 | */ |
| 552 | private static boolean isListProperty(String prop) { |
| 553 | prop = prop.intern(); |
| 554 | for (int i = 0; i < listProperties.length; i++) { |
| 555 | if (prop == listProperties[i]) { |
| 556 | return true; |
| 557 | } |
| 558 | } |
| 559 | return false; |
| 560 | } |
| 561 | } |