1 /* 2 * Copyright (c) 2000, 2010, 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 27 package java.util.logging; 28 29 import java.io.*; 30 import java.util.*; 31 import java.security.*; 32 import java.lang.ref.ReferenceQueue; 33 import java.lang.ref.WeakReference; 34 import java.beans.PropertyChangeListener; 35 import java.beans.PropertyChangeSupport; 36 import java.net.URL; 37 import sun.security.action.GetPropertyAction; 38 39 /** 40 * There is a single global LogManager object that is used to 41 * maintain a set of shared state about Loggers and log services. 42 * <p> 43 * This LogManager object: 44 * <ul> 45 * <li> Manages a hierarchical namespace of Logger objects. All 46 * named Loggers are stored in this namespace. 47 * <li> Manages a set of logging control properties. These are 48 * simple key-value pairs that can be used by Handlers and 49 * other logging objects to configure themselves. 50 * </ul> 51 * <p> 52 * The global LogManager object can be retrieved using LogManager.getLogManager(). 53 * The LogManager object is created during class initialization and 54 * cannot subsequently be changed. 55 * <p> 56 * At startup the LogManager class is located using the 57 * java.util.logging.manager system property. 58 * <p> 59 * By default, the LogManager reads its initial configuration from 60 * a properties file "lib/logging.properties" in the JRE directory. 61 * If you edit that property file you can change the default logging 62 * configuration for all uses of that JRE. 63 * <p> 64 * In addition, the LogManager uses two optional system properties that 65 * allow more control over reading the initial configuration: 66 * <ul> 67 * <li>"java.util.logging.config.class" 68 * <li>"java.util.logging.config.file" 69 * </ul> 70 * These two properties may be set via the Preferences API, or as 71 * command line property definitions to the "java" command, or as 72 * system property definitions passed to JNI_CreateJavaVM. 73 * <p> 74 * If the "java.util.logging.config.class" property is set, then the 75 * property value is treated as a class name. The given class will be 76 * loaded, an object will be instantiated, and that object's constructor 77 * is responsible for reading in the initial configuration. (That object 78 * may use other system properties to control its configuration.) The 79 * alternate configuration class can use <tt>readConfiguration(InputStream)</tt> 80 * to define properties in the LogManager. 81 * <p> 82 * If "java.util.logging.config.class" property is <b>not</b> set, 83 * then the "java.util.logging.config.file" system property can be used 84 * to specify a properties file (in java.util.Properties format). The 85 * initial logging configuration will be read from this file. 86 * <p> 87 * If neither of these properties is defined then, as described 88 * above, the LogManager will read its initial configuration from 89 * a properties file "lib/logging.properties" in the JRE directory. 90 * <p> 91 * The properties for loggers and Handlers will have names starting 92 * with the dot-separated name for the handler or logger. 93 * <p> 94 * The global logging properties may include: 95 * <ul> 96 * <li>A property "handlers". This defines a whitespace or comma separated 97 * list of class names for handler classes to load and register as 98 * handlers on the root Logger (the Logger named ""). Each class 99 * name must be for a Handler class which has a default constructor. 100 * Note that these Handlers may be created lazily, when they are 101 * first used. 102 * 103 * <li>A property "<logger>.handlers". This defines a whitespace or 104 * comma separated list of class names for handlers classes to 105 * load and register as handlers to the specified logger. Each class 106 * name must be for a Handler class which has a default constructor. 107 * Note that these Handlers may be created lazily, when they are 108 * first used. 109 * 110 * <li>A property "<logger>.useParentHandlers". This defines a boolean 111 * value. By default every logger calls its parent in addition to 112 * handling the logging message itself, this often result in messages 113 * being handled by the root logger as well. When setting this property 114 * to false a Handler needs to be configured for this logger otherwise 115 * no logging messages are delivered. 116 * 117 * <li>A property "config". This property is intended to allow 118 * arbitrary configuration code to be run. The property defines a 119 * whitespace or comma separated list of class names. A new instance will be 120 * created for each named class. The default constructor of each class 121 * may execute arbitrary code to update the logging configuration, such as 122 * setting logger levels, adding handlers, adding filters, etc. 123 * </ul> 124 * <p> 125 * Note that all classes loaded during LogManager configuration are 126 * first searched on the system class path before any user class path. 127 * That includes the LogManager class, any config classes, and any 128 * handler classes. 129 * <p> 130 * Loggers are organized into a naming hierarchy based on their 131 * dot separated names. Thus "a.b.c" is a child of "a.b", but 132 * "a.b1" and a.b2" are peers. 133 * <p> 134 * All properties whose names end with ".level" are assumed to define 135 * log levels for Loggers. Thus "foo.level" defines a log level for 136 * the logger called "foo" and (recursively) for any of its children 137 * in the naming hierarchy. Log Levels are applied in the order they 138 * are defined in the properties file. Thus level settings for child 139 * nodes in the tree should come after settings for their parents. 140 * The property name ".level" can be used to set the level for the 141 * root of the tree. 142 * <p> 143 * All methods on the LogManager object are multi-thread safe. 144 * 145 * @since 1.4 146 */ 147 148 public class LogManager { 149 // The global LogManager object 150 private static LogManager manager; 151 152 private final static Handler[] emptyHandlers = { }; 153 private Properties props = new Properties(); 154 private PropertyChangeSupport changes 155 = new PropertyChangeSupport(LogManager.class); 156 private final static Level defaultLevel = Level.INFO; 157 158 // Table of named Loggers that maps names to Loggers. 159 private Hashtable<String,LoggerWeakRef> namedLoggers = new Hashtable<>(); 160 // Tree of named Loggers 161 private LogNode root = new LogNode(null); 162 private Logger rootLogger; 163 164 // Have we done the primordial reading of the configuration file? 165 // (Must be done after a suitable amount of java.lang.System 166 // initialization has been done) 167 private volatile boolean readPrimordialConfiguration; 168 // Have we initialized global (root) handlers yet? 169 // This gets set to false in readConfiguration 170 private boolean initializedGlobalHandlers = true; 171 // True if JVM death is imminent and the exit hook has been called. 172 private boolean deathImminent; 173 174 static { 175 AccessController.doPrivileged(new PrivilegedAction<Object>() { 176 public Object run() { 177 String cname = null; 178 try { 179 cname = System.getProperty("java.util.logging.manager"); 180 if (cname != null) { 181 try { 182 Class clz = ClassLoader.getSystemClassLoader().loadClass(cname); 183 manager = (LogManager) clz.newInstance(); 184 } catch (ClassNotFoundException ex) { 185 Class clz = Thread.currentThread().getContextClassLoader().loadClass(cname); 186 manager = (LogManager) clz.newInstance(); 187 } 188 } 189 } catch (Exception ex) { 190 System.err.println("Could not load Logmanager \"" + cname + "\""); 191 ex.printStackTrace(); 192 } 193 if (manager == null) { 194 manager = new LogManager(); 195 } 196 197 // Create and retain Logger for the root of the namespace. 198 manager.rootLogger = manager.new RootLogger(); 199 manager.addLogger(manager.rootLogger); 200 201 // Adding the global Logger. Doing so in the Logger.<clinit> 202 // would deadlock with the LogManager.<clinit>. 203 Logger.global.setLogManager(manager); 204 manager.addLogger(Logger.global); 205 206 // We don't call readConfiguration() here, as we may be running 207 // very early in the JVM startup sequence. Instead readConfiguration 208 // will be called lazily in getLogManager(). 209 return null; 210 } 211 }); 212 } 213 214 215 // This private class is used as a shutdown hook. 216 // It does a "reset" to close all open handlers. 217 private class Cleaner extends Thread { 218 219 private Cleaner() { 220 /* Set context class loader to null in order to avoid 221 * keeping a strong reference to an application classloader. 222 */ 223 this.setContextClassLoader(null); 224 } 225 226 public void run() { 227 // This is to ensure the LogManager.<clinit> is completed 228 // before synchronized block. Otherwise deadlocks are possible. 229 LogManager mgr = manager; 230 231 // If the global handlers haven't been initialized yet, we 232 // don't want to initialize them just so we can close them! 233 synchronized (LogManager.this) { 234 // Note that death is imminent. 235 deathImminent = true; 236 initializedGlobalHandlers = true; 237 } 238 239 // Do a reset to close all active handlers. 240 reset(); 241 } 242 } 243 244 245 /** 246 * Protected constructor. This is protected so that container applications 247 * (such as J2EE containers) can subclass the object. It is non-public as 248 * it is intended that there only be one LogManager object, whose value is 249 * retrieved by calling Logmanager.getLogManager. 250 */ 251 protected LogManager() { 252 // Add a shutdown hook to close the global handlers. 253 try { 254 Runtime.getRuntime().addShutdownHook(new Cleaner()); 255 } catch (IllegalStateException e) { 256 // If the VM is already shutting down, 257 // We do not need to register shutdownHook. 258 } 259 } 260 261 /** 262 * Return the global LogManager object. 263 */ 264 public static LogManager getLogManager() { 265 if (manager != null) { 266 manager.readPrimordialConfiguration(); 267 } 268 return manager; 269 } 270 271 private void readPrimordialConfiguration() { 272 if (!readPrimordialConfiguration) { 273 synchronized (this) { 274 if (!readPrimordialConfiguration) { 275 // If System.in/out/err are null, it's a good 276 // indication that we're still in the 277 // bootstrapping phase 278 if (System.out == null) { 279 return; 280 } 281 readPrimordialConfiguration = true; 282 try { 283 AccessController.doPrivileged(new PrivilegedExceptionAction<Object>() { 284 public Object run() throws Exception { 285 readConfiguration(); 286 287 // Platform loggers begin to delegate to java.util.logging.Logger 288 sun.util.logging.PlatformLogger.redirectPlatformLoggers(); 289 290 return null; 291 } 292 }); 293 } catch (Exception ex) { 294 // System.err.println("Can't read logging configuration:"); 295 // ex.printStackTrace(); 296 } 297 } 298 } 299 } 300 } 301 302 /** 303 * Adds an event listener to be invoked when the logging 304 * properties are re-read. Adding multiple instances of 305 * the same event Listener results in multiple entries 306 * in the property event listener table. 307 * 308 * @param l event listener 309 * @exception SecurityException if a security manager exists and if 310 * the caller does not have LoggingPermission("control"). 311 * @exception NullPointerException if the PropertyChangeListener is null. 312 */ 313 public void addPropertyChangeListener(PropertyChangeListener l) throws SecurityException { 314 if (l == null) { 315 throw new NullPointerException(); 316 } 317 checkAccess(); 318 changes.addPropertyChangeListener(l); 319 } 320 321 /** 322 * Removes an event listener for property change events. 323 * If the same listener instance has been added to the listener table 324 * through multiple invocations of <CODE>addPropertyChangeListener</CODE>, 325 * then an equivalent number of 326 * <CODE>removePropertyChangeListener</CODE> invocations are required to remove 327 * all instances of that listener from the listener table. 328 * <P> 329 * Returns silently if the given listener is not found. 330 * 331 * @param l event listener (can be null) 332 * @exception SecurityException if a security manager exists and if 333 * the caller does not have LoggingPermission("control"). 334 */ 335 public void removePropertyChangeListener(PropertyChangeListener l) throws SecurityException { 336 checkAccess(); 337 changes.removePropertyChangeListener(l); 338 } 339 340 // Package-level method. 341 // Find or create a specified logger instance. If a logger has 342 // already been created with the given name it is returned. 343 // Otherwise a new logger instance is created and registered 344 // in the LogManager global namespace. 345 Logger demandLogger(String name) { 346 Logger result = getLogger(name); 347 if (result == null) { 348 result = new Logger(name, null); 349 addLogger(result); 350 result = getLogger(name); 351 } 352 return result; 353 } 354 355 // If logger.getUseParentHandlers() returns 'true' and any of the logger's 356 // parents have levels or handlers defined, make sure they are instantiated. 357 private void processParentHandlers(Logger logger, String name) { 358 int ix = 1; 359 for (;;) { 360 int ix2 = name.indexOf(".", ix); 361 if (ix2 < 0) { 362 break; 363 } 364 String pname = name.substring(0,ix2); 365 366 if (getProperty(pname+".level") != null || 367 getProperty(pname+".handlers") != null) { 368 // This pname has a level/handlers definition. 369 // Make sure it exists. 370 demandLogger(pname); 371 } 372 ix = ix2+1; 373 } 374 } 375 376 // Add new per logger handlers. 377 // We need to raise privilege here. All our decisions will 378 // be made based on the logging configuration, which can 379 // only be modified by trusted code. 380 private void loadLoggerHandlers(final Logger logger, final String name, 381 final String handlersPropertyName) { 382 AccessController.doPrivileged(new PrivilegedAction<Object>() { 383 public Object run() { 384 if (logger != rootLogger) { 385 boolean useParent = getBooleanProperty(name + ".useParentHandlers", true); 386 if (!useParent) { 387 logger.setUseParentHandlers(false); 388 } 389 } 390 391 String names[] = parseClassNames(handlersPropertyName); 392 for (int i = 0; i < names.length; i++) { 393 String word = names[i]; 394 try { 395 Class clz = ClassLoader.getSystemClassLoader().loadClass(word); 396 Handler hdl = (Handler) clz.newInstance(); 397 try { 398 // Check if there is a property defining the 399 // this handler's level. 400 String levs = getProperty(word + ".level"); 401 if (levs != null) { 402 hdl.setLevel(Level.parse(levs)); 403 } 404 } catch (Exception ex) { 405 System.err.println("Can't set level for " + word); 406 // Probably a bad level. Drop through. 407 } 408 // Add this Handler to the logger 409 logger.addHandler(hdl); 410 } catch (Exception ex) { 411 System.err.println("Can't load log handler \"" + word + "\""); 412 System.err.println("" + ex); 413 ex.printStackTrace(); 414 } 415 } 416 return null; 417 }}); 418 } 419 420 421 // loggerRefQueue holds LoggerWeakRef objects for Logger objects 422 // that have been GC'ed. 423 private final ReferenceQueue<Logger> loggerRefQueue 424 = new ReferenceQueue<>(); 425 426 // Package-level inner class. 427 // Helper class for managing WeakReferences to Logger objects. 428 // 429 // LogManager.namedLoggers 430 // - has weak references to all named Loggers 431 // - namedLoggers keeps the LoggerWeakRef objects for the named 432 // Loggers around until we can deal with the book keeping for 433 // the named Logger that is being GC'ed. 434 // LogManager.LogNode.loggerRef 435 // - has a weak reference to a named Logger 436 // - the LogNode will also keep the LoggerWeakRef objects for 437 // the named Loggers around; currently LogNodes never go away. 438 // Logger.kids 439 // - has a weak reference to each direct child Logger; this 440 // includes anonymous and named Loggers 441 // - anonymous Loggers are always children of the rootLogger 442 // which is a strong reference; rootLogger.kids keeps the 443 // LoggerWeakRef objects for the anonymous Loggers around 444 // until we can deal with the book keeping. 445 // 446 final class LoggerWeakRef extends WeakReference<Logger> { 447 private String name; // for namedLoggers cleanup 448 private LogNode node; // for loggerRef cleanup 449 private WeakReference<Logger> parentRef; // for kids cleanup 450 451 LoggerWeakRef(Logger logger) { 452 super(logger, loggerRefQueue); 453 454 name = logger.getName(); // save for namedLoggers cleanup 455 } 456 457 // dispose of this LoggerWeakRef object 458 void dispose() { 459 if (node != null) { 460 // if we have a LogNode, then we were a named Logger 461 // so clear namedLoggers weak ref to us 462 manager.namedLoggers.remove(name); 463 name = null; // clear our ref to the Logger's name 464 465 node.loggerRef = null; // clear LogNode's weak ref to us 466 node = null; // clear our ref to LogNode 467 } 468 469 if (parentRef != null) { 470 // this LoggerWeakRef has or had a parent Logger 471 Logger parent = parentRef.get(); 472 if (parent != null) { 473 // the parent Logger is still there so clear the 474 // parent Logger's weak ref to us 475 parent.removeChildLogger(this); 476 } 477 parentRef = null; // clear our weak ref to the parent Logger 478 } 479 } 480 481 // set the node field to the specified value 482 void setNode(LogNode node) { 483 this.node = node; 484 } 485 486 // set the parentRef field to the specified value 487 void setParentRef(WeakReference<Logger> parentRef) { 488 this.parentRef = parentRef; 489 } 490 } 491 492 // Package-level method. 493 // Drain some Logger objects that have been GC'ed. 494 // 495 // drainLoggerRefQueueBounded() is called by addLogger() below 496 // and by Logger.getAnonymousLogger(String) so we'll drain up to 497 // MAX_ITERATIONS GC'ed Loggers for every Logger we add. 498 // 499 // On a WinXP VMware client, a MAX_ITERATIONS value of 400 gives 500 // us about a 50/50 mix in increased weak ref counts versus 501 // decreased weak ref counts in the AnonLoggerWeakRefLeak test. 502 // Here are stats for cleaning up sets of 400 anonymous Loggers: 503 // - test duration 1 minute 504 // - sample size of 125 sets of 400 505 // - average: 1.99 ms 506 // - minimum: 0.57 ms 507 // - maximum: 25.3 ms 508 // 509 // The same config gives us a better decreased weak ref count 510 // than increased weak ref count in the LoggerWeakRefLeak test. 511 // Here are stats for cleaning up sets of 400 named Loggers: 512 // - test duration 2 minutes 513 // - sample size of 506 sets of 400 514 // - average: 0.57 ms 515 // - minimum: 0.02 ms 516 // - maximum: 10.9 ms 517 // 518 private final static int MAX_ITERATIONS = 400; 519 final synchronized void drainLoggerRefQueueBounded() { 520 for (int i = 0; i < MAX_ITERATIONS; i++) { 521 if (loggerRefQueue == null) { 522 // haven't finished loading LogManager yet 523 break; 524 } 525 526 LoggerWeakRef ref = (LoggerWeakRef) loggerRefQueue.poll(); 527 if (ref == null) { 528 break; 529 } 530 // a Logger object has been GC'ed so clean it up 531 ref.dispose(); 532 } 533 } 534 535 /** 536 * Add a named logger. This does nothing and returns false if a logger 537 * with the same name is already registered. 538 * <p> 539 * The Logger factory methods call this method to register each 540 * newly created Logger. 541 * <p> 542 * The application should retain its own reference to the Logger 543 * object to avoid it being garbage collected. The LogManager 544 * may only retain a weak reference. 545 * 546 * @param logger the new logger. 547 * @return true if the argument logger was registered successfully, 548 * false if a logger of that name already exists. 549 * @exception NullPointerException if the logger name is null. 550 */ 551 public synchronized boolean addLogger(Logger logger) { 552 final String name = logger.getName(); 553 if (name == null) { 554 throw new NullPointerException(); 555 } 556 557 // cleanup some Loggers that have been GC'ed 558 drainLoggerRefQueueBounded(); 559 560 LoggerWeakRef ref = namedLoggers.get(name); 561 if (ref != null) { 562 if (ref.get() == null) { 563 // It's possible that the Logger was GC'ed after the 564 // drainLoggerRefQueueBounded() call above so allow 565 // a new one to be registered. 566 namedLoggers.remove(name); 567 } else { 568 // We already have a registered logger with the given name. 569 return false; 570 } 571 } 572 573 // We're adding a new logger. 574 // Note that we are creating a weak reference here. 575 ref = new LoggerWeakRef(logger); 576 namedLoggers.put(name, ref); 577 578 // Apply any initial level defined for the new logger. 579 Level level = getLevelProperty(name+".level", null); 580 if (level != null) { 581 doSetLevel(logger, level); 582 } 583 584 // Do we have a per logger handler too? 585 // Note: this will add a 200ms penalty 586 loadLoggerHandlers(logger, name, name+".handlers"); 587 processParentHandlers(logger, name); 588 589 // Find the new node and its parent. 590 LogNode node = findNode(name); 591 node.loggerRef = ref; 592 Logger parent = null; 593 LogNode nodep = node.parent; 594 while (nodep != null) { 595 LoggerWeakRef nodeRef = nodep.loggerRef; 596 if (nodeRef != null) { 597 parent = nodeRef.get(); 598 if (parent != null) { 599 break; 600 } 601 } 602 nodep = nodep.parent; 603 } 604 605 if (parent != null) { 606 doSetParent(logger, parent); 607 } 608 // Walk over the children and tell them we are their new parent. 609 node.walkAndSetParent(logger); 610 611 // new LogNode is ready so tell the LoggerWeakRef about it 612 ref.setNode(node); 613 614 return true; 615 } 616 617 618 // Private method to set a level on a logger. 619 // If necessary, we raise privilege before doing the call. 620 private static void doSetLevel(final Logger logger, final Level level) { 621 SecurityManager sm = System.getSecurityManager(); 622 if (sm == null) { 623 // There is no security manager, so things are easy. 624 logger.setLevel(level); 625 return; 626 } 627 // There is a security manager. Raise privilege before 628 // calling setLevel. 629 AccessController.doPrivileged(new PrivilegedAction<Object>() { 630 public Object run() { 631 logger.setLevel(level); 632 return null; 633 }}); 634 } 635 636 637 638 // Private method to set a parent on a logger. 639 // If necessary, we raise privilege before doing the setParent call. 640 private static void doSetParent(final Logger logger, final Logger parent) { 641 SecurityManager sm = System.getSecurityManager(); 642 if (sm == null) { 643 // There is no security manager, so things are easy. 644 logger.setParent(parent); 645 return; 646 } 647 // There is a security manager. Raise privilege before 648 // calling setParent. 649 AccessController.doPrivileged(new PrivilegedAction<Object>() { 650 public Object run() { 651 logger.setParent(parent); 652 return null; 653 }}); 654 } 655 656 // Find a node in our tree of logger nodes. 657 // If necessary, create it. 658 private LogNode findNode(String name) { 659 if (name == null || name.equals("")) { 660 return root; 661 } 662 LogNode node = root; 663 while (name.length() > 0) { 664 int ix = name.indexOf("."); 665 String head; 666 if (ix > 0) { 667 head = name.substring(0,ix); 668 name = name.substring(ix+1); 669 } else { 670 head = name; 671 name = ""; 672 } 673 if (node.children == null) { 674 node.children = new HashMap<>(); 675 } 676 LogNode child = node.children.get(head); 677 if (child == null) { 678 child = new LogNode(node); 679 node.children.put(head, child); 680 } 681 node = child; 682 } 683 return node; 684 } 685 686 /** 687 * Method to find a named logger. 688 * <p> 689 * Note that since untrusted code may create loggers with 690 * arbitrary names this method should not be relied on to 691 * find Loggers for security sensitive logging. 692 * It is also important to note that the Logger associated with the 693 * String {@code name} may be garbage collected at any time if there 694 * is no strong reference to the Logger. The caller of this method 695 * must check the return value for null in order to properly handle 696 * the case where the Logger has been garbage collected. 697 * <p> 698 * @param name name of the logger 699 * @return matching logger or null if none is found 700 */ 701 public synchronized Logger getLogger(String name) { 702 LoggerWeakRef ref = namedLoggers.get(name); 703 if (ref == null) { 704 return null; 705 } 706 Logger logger = ref.get(); 707 if (logger == null) { 708 // Hashtable holds stale weak reference 709 // to a logger which has been GC-ed. 710 namedLoggers.remove(name); 711 } 712 return logger; 713 } 714 715 /** 716 * Get an enumeration of known logger names. 717 * <p> 718 * Note: Loggers may be added dynamically as new classes are loaded. 719 * This method only reports on the loggers that are currently registered. 720 * It is also important to note that this method only returns the name 721 * of a Logger, not a strong reference to the Logger itself. 722 * The returned String does nothing to prevent the Logger from being 723 * garbage collected. In particular, if the returned name is passed 724 * to {@code LogManager.getLogger()}, then the caller must check the 725 * return value from {@code LogManager.getLogger()} for null to properly 726 * handle the case where the Logger has been garbage collected in the 727 * time since its name was returned by this method. 728 * <p> 729 * @return enumeration of logger name strings 730 */ 731 public synchronized Enumeration<String> getLoggerNames() { 732 return namedLoggers.keys(); 733 } 734 735 /** 736 * Reinitialize the logging properties and reread the logging configuration. 737 * <p> 738 * The same rules are used for locating the configuration properties 739 * as are used at startup. So normally the logging properties will 740 * be re-read from the same file that was used at startup. 741 * <P> 742 * Any log level definitions in the new configuration file will be 743 * applied using Logger.setLevel(), if the target Logger exists. 744 * <p> 745 * A PropertyChangeEvent will be fired after the properties are read. 746 * 747 * @exception SecurityException if a security manager exists and if 748 * the caller does not have LoggingPermission("control"). 749 * @exception IOException if there are IO problems reading the configuration. 750 */ 751 public void readConfiguration() throws IOException, SecurityException { 752 checkAccess(); 753 754 // if a configuration class is specified, load it and use it. 755 String cname = System.getProperty("java.util.logging.config.class"); 756 if (cname != null) { 757 try { 758 // Instantiate the named class. It is its constructor's 759 // responsibility to initialize the logging configuration, by 760 // calling readConfiguration(InputStream) with a suitable stream. 761 try { 762 Class clz = ClassLoader.getSystemClassLoader().loadClass(cname); 763 clz.newInstance(); 764 return; 765 } catch (ClassNotFoundException ex) { 766 Class clz = Thread.currentThread().getContextClassLoader().loadClass(cname); 767 clz.newInstance(); 768 return; 769 } 770 } catch (Exception ex) { 771 System.err.println("Logging configuration class \"" + cname + "\" failed"); 772 System.err.println("" + ex); 773 // keep going and useful config file. 774 } 775 } 776 777 String fname = System.getProperty("java.util.logging.config.file"); 778 if (fname == null) { 779 fname = System.getProperty("java.home"); 780 if (fname == null) { 781 throw new Error("Can't find java.home ??"); 782 } 783 File f = new File(fname, "lib"); 784 f = new File(f, "logging.properties"); 785 fname = f.getCanonicalPath(); 786 } 787 InputStream in = new FileInputStream(fname); 788 BufferedInputStream bin = new BufferedInputStream(in); 789 try { 790 readConfiguration(bin); 791 } finally { 792 if (in != null) { 793 in.close(); 794 } 795 } 796 } 797 798 /** 799 * Reset the logging configuration. 800 * <p> 801 * For all named loggers, the reset operation removes and closes 802 * all Handlers and (except for the root logger) sets the level 803 * to null. The root logger's level is set to Level.INFO. 804 * 805 * @exception SecurityException if a security manager exists and if 806 * the caller does not have LoggingPermission("control"). 807 */ 808 809 public void reset() throws SecurityException { 810 checkAccess(); 811 synchronized (this) { 812 props = new Properties(); 813 // Since we are doing a reset we no longer want to initialize 814 // the global handlers, if they haven't been initialized yet. 815 initializedGlobalHandlers = true; 816 } 817 Enumeration enum_ = getLoggerNames(); 818 while (enum_.hasMoreElements()) { 819 String name = (String)enum_.nextElement(); 820 resetLogger(name); 821 } 822 } 823 824 825 // Private method to reset an individual target logger. 826 private void resetLogger(String name) { 827 Logger logger = getLogger(name); 828 if (logger == null) { 829 return; 830 } 831 // Close all the Logger's handlers. 832 Handler[] targets = logger.getHandlers(); 833 for (int i = 0; i < targets.length; i++) { 834 Handler h = targets[i]; 835 logger.removeHandler(h); 836 try { 837 h.close(); 838 } catch (Exception ex) { 839 // Problems closing a handler? Keep going... 840 } 841 } 842 if (name != null && name.equals("")) { 843 // This is the root logger. 844 logger.setLevel(defaultLevel); 845 } else { 846 logger.setLevel(null); 847 } 848 } 849 850 // get a list of whitespace separated classnames from a property. 851 private String[] parseClassNames(String propertyName) { 852 String hands = getProperty(propertyName); 853 if (hands == null) { 854 return new String[0]; 855 } 856 hands = hands.trim(); 857 int ix = 0; 858 Vector<String> result = new Vector<>(); 859 while (ix < hands.length()) { 860 int end = ix; 861 while (end < hands.length()) { 862 if (Character.isWhitespace(hands.charAt(end))) { 863 break; 864 } 865 if (hands.charAt(end) == ',') { 866 break; 867 } 868 end++; 869 } 870 String word = hands.substring(ix, end); 871 ix = end+1; 872 word = word.trim(); 873 if (word.length() == 0) { 874 continue; 875 } 876 result.add(word); 877 } 878 return result.toArray(new String[result.size()]); 879 } 880 881 /** 882 * Reinitialize the logging properties and reread the logging configuration 883 * from the given stream, which should be in java.util.Properties format. 884 * A PropertyChangeEvent will be fired after the properties are read. 885 * <p> 886 * Any log level definitions in the new configuration file will be 887 * applied using Logger.setLevel(), if the target Logger exists. 888 * 889 * @param ins stream to read properties from 890 * @exception SecurityException if a security manager exists and if 891 * the caller does not have LoggingPermission("control"). 892 * @exception IOException if there are problems reading from the stream. 893 */ 894 public void readConfiguration(InputStream ins) throws IOException, SecurityException { 895 checkAccess(); 896 reset(); 897 898 // Load the properties 899 props.load(ins); 900 // Instantiate new configuration objects. 901 String names[] = parseClassNames("config"); 902 903 for (int i = 0; i < names.length; i++) { 904 String word = names[i]; 905 try { 906 Class clz = ClassLoader.getSystemClassLoader().loadClass(word); 907 clz.newInstance(); 908 } catch (Exception ex) { 909 System.err.println("Can't load config class \"" + word + "\""); 910 System.err.println("" + ex); 911 // ex.printStackTrace(); 912 } 913 } 914 915 // Set levels on any pre-existing loggers, based on the new properties. 916 setLevelsOnExistingLoggers(); 917 918 // Notify any interested parties that our properties have changed. 919 changes.firePropertyChange(null, null, null); 920 921 // Note that we need to reinitialize global handles when 922 // they are first referenced. 923 synchronized (this) { 924 initializedGlobalHandlers = false; 925 } 926 } 927 928 /** 929 * Get the value of a logging property. 930 * The method returns null if the property is not found. 931 * @param name property name 932 * @return property value 933 */ 934 public String getProperty(String name) { 935 return props.getProperty(name); 936 } 937 938 // Package private method to get a String property. 939 // If the property is not defined we return the given 940 // default value. 941 String getStringProperty(String name, String defaultValue) { 942 String val = getProperty(name); 943 if (val == null) { 944 return defaultValue; 945 } 946 return val.trim(); 947 } 948 949 // Package private method to get an integer property. 950 // If the property is not defined or cannot be parsed 951 // we return the given default value. 952 int getIntProperty(String name, int defaultValue) { 953 String val = getProperty(name); 954 if (val == null) { 955 return defaultValue; 956 } 957 try { 958 return Integer.parseInt(val.trim()); 959 } catch (Exception ex) { 960 return defaultValue; 961 } 962 } 963 964 // Package private method to get a boolean property. 965 // If the property is not defined or cannot be parsed 966 // we return the given default value. 967 boolean getBooleanProperty(String name, boolean defaultValue) { 968 String val = getProperty(name); 969 if (val == null) { 970 return defaultValue; 971 } 972 val = val.toLowerCase(); 973 if (val.equals("true") || val.equals("1")) { 974 return true; 975 } else if (val.equals("false") || val.equals("0")) { 976 return false; 977 } 978 return defaultValue; 979 } 980 981 // Package private method to get a Level property. 982 // If the property is not defined or cannot be parsed 983 // we return the given default value. 984 Level getLevelProperty(String name, Level defaultValue) { 985 String val = getProperty(name); 986 if (val == null) { 987 return defaultValue; 988 } 989 try { 990 return Level.parse(val.trim()); 991 } catch (Exception ex) { 992 return defaultValue; 993 } 994 } 995 996 // Package private method to get a filter property. 997 // We return an instance of the class named by the "name" 998 // property. If the property is not defined or has problems 999 // we return the defaultValue. 1000 Filter getFilterProperty(String name, Filter defaultValue) { 1001 String val = getProperty(name); 1002 try { 1003 if (val != null) { 1004 Class clz = ClassLoader.getSystemClassLoader().loadClass(val); 1005 return (Filter) clz.newInstance(); 1006 } 1007 } catch (Exception ex) { 1008 // We got one of a variety of exceptions in creating the 1009 // class or creating an instance. 1010 // Drop through. 1011 } 1012 // We got an exception. Return the defaultValue. 1013 return defaultValue; 1014 } 1015 1016 1017 // Package private method to get a formatter property. 1018 // We return an instance of the class named by the "name" 1019 // property. If the property is not defined or has problems 1020 // we return the defaultValue. 1021 Formatter getFormatterProperty(String name, Formatter defaultValue) { 1022 String val = getProperty(name); 1023 try { 1024 if (val != null) { 1025 Class clz = ClassLoader.getSystemClassLoader().loadClass(val); 1026 return (Formatter) clz.newInstance(); 1027 } 1028 } catch (Exception ex) { 1029 // We got one of a variety of exceptions in creating the 1030 // class or creating an instance. 1031 // Drop through. 1032 } 1033 // We got an exception. Return the defaultValue. 1034 return defaultValue; 1035 } 1036 1037 // Private method to load the global handlers. 1038 // We do the real work lazily, when the global handlers 1039 // are first used. 1040 private synchronized void initializeGlobalHandlers() { 1041 if (initializedGlobalHandlers) { 1042 return; 1043 } 1044 1045 initializedGlobalHandlers = true; 1046 1047 if (deathImminent) { 1048 // Aaargh... 1049 // The VM is shutting down and our exit hook has been called. 1050 // Avoid allocating global handlers. 1051 return; 1052 } 1053 loadLoggerHandlers(rootLogger, null, "handlers"); 1054 } 1055 1056 1057 private Permission ourPermission = new LoggingPermission("control", null); 1058 1059 /** 1060 * Check that the current context is trusted to modify the logging 1061 * configuration. This requires LoggingPermission("control"). 1062 * <p> 1063 * If the check fails we throw a SecurityException, otherwise 1064 * we return normally. 1065 * 1066 * @exception SecurityException if a security manager exists and if 1067 * the caller does not have LoggingPermission("control"). 1068 */ 1069 public void checkAccess() throws SecurityException { 1070 SecurityManager sm = System.getSecurityManager(); 1071 if (sm == null) { 1072 return; 1073 } 1074 sm.checkPermission(ourPermission); 1075 } 1076 1077 // Nested class to represent a node in our tree of named loggers. 1078 private static class LogNode { 1079 HashMap<String,LogNode> children; 1080 LoggerWeakRef loggerRef; 1081 LogNode parent; 1082 1083 LogNode(LogNode parent) { 1084 this.parent = parent; 1085 } 1086 1087 // Recursive method to walk the tree below a node and set 1088 // a new parent logger. 1089 void walkAndSetParent(Logger parent) { 1090 if (children == null) { 1091 return; 1092 } 1093 Iterator<LogNode> values = children.values().iterator(); 1094 while (values.hasNext()) { 1095 LogNode node = values.next(); 1096 LoggerWeakRef ref = node.loggerRef; 1097 Logger logger = (ref == null) ? null : ref.get(); 1098 if (logger == null) { 1099 node.walkAndSetParent(parent); 1100 } else { 1101 doSetParent(logger, parent); 1102 } 1103 } 1104 } 1105 } 1106 1107 // We use a subclass of Logger for the root logger, so 1108 // that we only instantiate the global handlers when they 1109 // are first needed. 1110 private class RootLogger extends Logger { 1111 1112 private RootLogger() { 1113 super("", null); 1114 setLevel(defaultLevel); 1115 } 1116 1117 public void log(LogRecord record) { 1118 // Make sure that the global handlers have been instantiated. 1119 initializeGlobalHandlers(); 1120 super.log(record); 1121 } 1122 1123 public void addHandler(Handler h) { 1124 initializeGlobalHandlers(); 1125 super.addHandler(h); 1126 } 1127 1128 public void removeHandler(Handler h) { 1129 initializeGlobalHandlers(); 1130 super.removeHandler(h); 1131 } 1132 1133 public Handler[] getHandlers() { 1134 initializeGlobalHandlers(); 1135 return super.getHandlers(); 1136 } 1137 } 1138 1139 1140 // Private method to be called when the configuration has 1141 // changed to apply any level settings to any pre-existing loggers. 1142 synchronized private void setLevelsOnExistingLoggers() { 1143 Enumeration enum_ = props.propertyNames(); 1144 while (enum_.hasMoreElements()) { 1145 String key = (String)enum_.nextElement(); 1146 if (!key.endsWith(".level")) { 1147 // Not a level definition. 1148 continue; 1149 } 1150 int ix = key.length() - 6; 1151 String name = key.substring(0, ix); 1152 Level level = getLevelProperty(key, null); 1153 if (level == null) { 1154 System.err.println("Bad level value for property: " + key); 1155 continue; 1156 } 1157 Logger l = getLogger(name); 1158 if (l == null) { 1159 continue; 1160 } 1161 l.setLevel(level); 1162 } 1163 } 1164 1165 // Management Support 1166 private static LoggingMXBean loggingMXBean = null; 1167 /** 1168 * String representation of the 1169 * {@link javax.management.ObjectName} for the management interface 1170 * for the logging facility. 1171 * 1172 * @see java.lang.management.PlatformLoggingMXBean 1173 * @see java.util.logging.LoggingMXBean 1174 * 1175 * @since 1.5 1176 */ 1177 public final static String LOGGING_MXBEAN_NAME 1178 = "java.util.logging:type=Logging"; 1179 1180 /** 1181 * Returns <tt>LoggingMXBean</tt> for managing loggers. 1182 * An alternative way to manage loggers is through the 1183 * {@link java.lang.management.PlatformLoggingMXBean} interface 1184 * that can be obtained by calling: 1185 * <pre> 1186 * PlatformLoggingMXBean logging = {@link java.lang.management.ManagementFactory#getPlatformMXBean(Class) 1187 * ManagementFactory.getPlatformMXBean}(PlatformLoggingMXBean.class); 1188 * </pre> 1189 * 1190 * @return a {@link LoggingMXBean} object. 1191 * 1192 * @see java.lang.management.PlatformLoggingMXBean 1193 * @since 1.5 1194 */ 1195 public static synchronized LoggingMXBean getLoggingMXBean() { 1196 if (loggingMXBean == null) { 1197 loggingMXBean = new Logging(); 1198 } 1199 return loggingMXBean; 1200 } 1201 1202 }