CApplication.php 27.3 KB
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889
<?php
/**
 * CApplication class file.
 *
 * @author Qiang Xue <qiang.xue@gmail.com>
 * @link http://www.yiiframework.com/
 * @copyright Copyright &copy; 2008-2011 Yii Software LLC
 * @license http://www.yiiframework.com/license/
 */

/**
 * CApplication is the base class for all application classes.
 *
 * An application serves as the global context that the user request
 * is being processed. It manages a set of application components that
 * provide specific functionalities to the whole application.
 *
 * The core application components provided by CApplication are the following:
 * <ul>
 * <li>{@link getErrorHandler errorHandler}: handles PHP errors and
 *   uncaught exceptions. This application component is dynamically loaded when needed.</li>
 * <li>{@link getSecurityManager securityManager}: provides security-related
 *   services, such as hashing, encryption. This application component is dynamically
 *   loaded when needed.</li>
 * <li>{@link getStatePersister statePersister}: provides global state
 *   persistence method. This application component is dynamically loaded when needed.</li>
 * <li>{@link getCache cache}: provides caching feature. This application component is
 *   disabled by default.</li>
 * <li>{@link getMessages messages}: provides the message source for translating
 *   application messages. This application component is dynamically loaded when needed.</li>
 * <li>{@link getCoreMessages coreMessages}: provides the message source for translating
 *   Yii framework messages. This application component is dynamically loaded when needed.</li>
 * </ul>
 *
 * CApplication will undergo the following lifecycles when processing a user request:
 * <ol>
 * <li>load application configuration;</li>
 * <li>set up class autoloader and error handling;</li>
 * <li>load static application components;</li>
 * <li>{@link onBeginRequest}: preprocess the user request;</li>
 * <li>{@link processRequest}: process the user request;</li>
 * <li>{@link onEndRequest}: postprocess the user request;</li>
 * </ol>
 *
 * Starting from lifecycle 3, if a PHP error or an uncaught exception occurs,
 * the application will switch to its error handling logic and jump to step 6 afterwards.
 *
 * @author Qiang Xue <qiang.xue@gmail.com>
 * @version $Id: CApplication.php 2799 2011-01-01 19:31:13Z qiang.xue $
 * @package system.base
 * @since 1.0
 *
 * @property string $basePath Returns the root path of the application.
 * @property CCache $cache Returns the cache component.
 * @property CPhpMessageSource $coreMessages Returns the core message translations.
 * @property CDateFormatter $dateFormatter Returns the locale-dependent date formatter.
 * @property CDbConnection $db Returns the database connection component.
 * @property CErrorHandler $errorHandler Returns the error handler component.
 * @property string $extensionPath Returns the root directory that holds all third-party extensions.
 * @property string $id Returns the unique identifier for the application.
 * @property string $language Returns the language that the user is using and the application should be targeted to.
 * @property CLocale $locale Returns the locale instance.
 * @property string $localeDataPath Returns the directory that contains the locale data.
 * @property CMessageSource $messages Returns the application message translations component.
 * @property CNumberFormatter $numberFormatter The locale-dependent number formatter.
 * @property CHttpRequest $request Returns the request component.
 * @property string $runtimePath Returns the directory that stores runtime files.
 * @property CSecurityManager $securityManager Returns the security manager component.
 * @property CStatePersister $statePersister Returns the state persister component.
 * @property string $timeZone Returns the time zone used by this application.
 * @property CUrlManager $urlManager Returns the URL manager component.
 */
abstract class CApplication extends CModule
{
	/**
	 * @var string the application name. Defaults to 'My Application'.
	 */
	public $name='My Application';
	/**
	 * @var string the charset currently used for the application. Defaults to 'UTF-8'.
	 */
	public $charset='UTF-8';
	/**
	 * @var string the language that the application is written in. This mainly refers to
	 * the language that the messages and view files are in. Defaults to 'en_us' (US English).
	 */
	public $sourceLanguage='en_us';

	private $_id;
	private $_basePath;
	private $_runtimePath;
	private $_extensionPath;
	private $_globalState;
	private $_stateChanged;
	private $_ended=false;
	private $_language;

	/**
	 * Processes the request.
	 * This is the place where the actual request processing work is done.
	 * Derived classes should override this method.
	 */
	abstract public function processRequest();

	/**
	 * Constructor.
	 * @param mixed $config application configuration.
	 * If a string, it is treated as the path of the file that contains the configuration;
	 * If an array, it is the actual configuration information.
	 * Please make sure you specify the {@link getBasePath basePath} property in the configuration,
	 * which should point to the directory containing all application logic, template and data.
	 * If not, the directory will be defaulted to 'protected'.
	 */
	public function __construct($config=null)
	{
		Yii::setApplication($this);

		// set basePath at early as possible to avoid trouble
		if(is_string($config))
			$config=require($config);
		if(isset($config['basePath']))
		{
			$this->setBasePath($config['basePath']);
			unset($config['basePath']);
		}
		else
			$this->setBasePath('protected');
		Yii::setPathOfAlias('application',$this->getBasePath());
		Yii::setPathOfAlias('webroot',dirname($_SERVER['SCRIPT_FILENAME']));
		Yii::setPathOfAlias('ext',$this->getBasePath().DIRECTORY_SEPARATOR.'extensions');

		$this->preinit();

		$this->initSystemHandlers();
		$this->registerCoreComponents();

		$this->configure($config);
		$this->attachBehaviors($this->behaviors);
		$this->preloadComponents();

		$this->init();
	}


	/**
	 * Runs the application.
	 * This method loads static application components. Derived classes usually overrides this
	 * method to do more application-specific tasks.
	 * Remember to call the parent implementation so that static application components are loaded.
	 */
	public function run()
	{
		if($this->hasEventHandler('onBeginRequest'))
			$this->onBeginRequest(new CEvent($this));
		$this->processRequest();
		if($this->hasEventHandler('onEndRequest'))
			$this->onEndRequest(new CEvent($this));
	}

	/**
	 * Terminates the application.
	 * This method replaces PHP's exit() function by calling
	 * {@link onEndRequest} before exiting.
	 * @param integer $status exit status (value 0 means normal exit while other values mean abnormal exit).
	 * @param boolean $exit whether to exit the current request. This parameter has been available since version 1.1.5.
	 * It defaults to true, meaning the PHP's exit() function will be called at the end of this method.
	 */
	public function end($status=0, $exit=true)
	{
		if($this->hasEventHandler('onEndRequest'))
			$this->onEndRequest(new CEvent($this));
		if($exit)
			exit($status);
	}

	/**
	 * Raised right BEFORE the application processes the request.
	 * @param CEvent $event the event parameter
	 */
	public function onBeginRequest($event)
	{
		$this->raiseEvent('onBeginRequest',$event);
	}

	/**
	 * Raised right AFTER the application processes the request.
	 * @param CEvent $event the event parameter
	 */
	public function onEndRequest($event)
	{
		if(!$this->_ended)
		{
			$this->_ended=true;
			$this->raiseEvent('onEndRequest',$event);
		}
	}

	/**
	 * Returns the unique identifier for the application.
	 * @return string the unique identifier for the application.
	 */
	public function getId()
	{
		if($this->_id!==null)
			return $this->_id;
		else
			return $this->_id=sprintf('%x',crc32($this->getBasePath().$this->name));
	}

	/**
	 * Sets the unique identifier for the application.
	 * @param string $id the unique identifier for the application.
	 */
	public function setId($id)
	{
		$this->_id=$id;
	}

	/**
	 * Returns the root path of the application.
	 * @return string the root directory of the application. Defaults to 'protected'.
	 */
	public function getBasePath()
	{
		return $this->_basePath;
	}

	/**
	 * Sets the root directory of the application.
	 * This method can only be invoked at the begin of the constructor.
	 * @param string $path the root directory of the application.
	 * @throws CException if the directory does not exist.
	 */
	public function setBasePath($path)
	{
		if(($this->_basePath=realpath($path))===false || !is_dir($this->_basePath))
			throw new CException(Yii::t('yii','Application base path "{path}" is not a valid directory.',
				array('{path}'=>$path)));
	}

	/**
	 * Returns the directory that stores runtime files.
	 * @return string the directory that stores runtime files. Defaults to 'protected/runtime'.
	 */
	public function getRuntimePath()
	{
		if($this->_runtimePath!==null)
			return $this->_runtimePath;
		else
		{
			$this->setRuntimePath($this->getBasePath().DIRECTORY_SEPARATOR.'runtime');
			return $this->_runtimePath;
		}
	}

	/**
	 * Sets the directory that stores runtime files.
	 * @param string $path the directory that stores runtime files.
	 * @throws CException if the directory does not exist or is not writable
	 */
	public function setRuntimePath($path)
	{
		if(($runtimePath=realpath($path))===false || !is_dir($runtimePath) || !is_writable($runtimePath))
			throw new CException(Yii::t('yii','Application runtime path "{path}" is not valid. Please make sure it is a directory writable by the Web server process.',
				array('{path}'=>$path)));
		$this->_runtimePath=$runtimePath;
	}

	/**
	 * Returns the root directory that holds all third-party extensions.
	 * @return string the directory that contains all extensions. Defaults to the 'extensions' directory under 'protected'.
	 */
	public function getExtensionPath()
	{
		return Yii::getPathOfAlias('ext');
	}

	/**
	 * Sets the root directory that holds all third-party extensions.
	 * @param string $path the directory that contains all third-party extensions.
	 */
	public function setExtensionPath($path)
	{
		if(($extensionPath=realpath($path))===false || !is_dir($extensionPath))
			throw new CException(Yii::t('yii','Extension path "{path}" does not exist.',
				array('{path}'=>$path)));
		Yii::setPathOfAlias('ext',$extensionPath);
	}

	/**
	 * Returns the language that the user is using and the application should be targeted to.
	 * @return string the language that the user is using and the application should be targeted to.
	 * Defaults to the {@link sourceLanguage source language}.
	 */
	public function getLanguage()
	{
		return $this->_language===null ? $this->sourceLanguage : $this->_language;
	}

	/**
	 * Specifies which language the application is targeted to.
	 *
	 * This is the language that the application displays to end users.
	 * If set null, it uses the {@link sourceLanguage source language}.
	 *
	 * Unless your application needs to support multiple languages, you should always
	 * set this language to null to maximize the application's performance.
	 * @param string $language the user language (e.g. 'en_US', 'zh_CN').
	 * If it is null, the {@link sourceLanguage} will be used.
	 */
	public function setLanguage($language)
	{
		$this->_language=$language;
	}

	/**
	 * Returns the time zone used by this application.
	 * This is a simple wrapper of PHP function date_default_timezone_get().
	 * @return string the time zone used by this application.
	 * @see http://php.net/manual/en/function.date-default-timezone-get.php
	 * @since 1.0.9
	 */
	public function getTimeZone()
	{
		return date_default_timezone_get();
	}

	/**
	 * Sets the time zone used by this application.
	 * This is a simple wrapper of PHP function date_default_timezone_set().
	 * @param string $value the time zone used by this application.
	 * @see http://php.net/manual/en/function.date-default-timezone-set.php
	 * @since 1.0.9
	 */
	public function setTimeZone($value)
	{
		date_default_timezone_set($value);
	}

	/**
	 * Returns the localized version of a specified file.
	 *
	 * The searching is based on the specified language code. In particular,
	 * a file with the same name will be looked for under the subdirectory
	 * named as the locale ID. For example, given the file "path/to/view.php"
	 * and locale ID "zh_cn", the localized file will be looked for as
	 * "path/to/zh_cn/view.php". If the file is not found, the original file
	 * will be returned.
	 *
	 * For consistency, it is recommended that the locale ID is given
	 * in lower case and in the format of LanguageID_RegionID (e.g. "en_us").
	 *
	 * @param string $srcFile the original file
	 * @param string $srcLanguage the language that the original file is in. If null, the application {@link sourceLanguage source language} is used.
	 * @param string $language the desired language that the file should be localized to. If null, the {@link getLanguage application language} will be used.
	 * @return string the matching localized file. The original file is returned if no localized version is found
	 * or if source language is the same as the desired language.
	 */
	public function findLocalizedFile($srcFile,$srcLanguage=null,$language=null)
	{
		if($srcLanguage===null)
			$srcLanguage=$this->sourceLanguage;
		if($language===null)
			$language=$this->getLanguage();
		if($language===$srcLanguage)
			return $srcFile;
		$desiredFile=dirname($srcFile).DIRECTORY_SEPARATOR.$language.DIRECTORY_SEPARATOR.basename($srcFile);
		return is_file($desiredFile) ? $desiredFile : $srcFile;
	}

	/**
	 * Returns the locale instance.
	 * @param string $localeID the locale ID (e.g. en_US). If null, the {@link getLanguage application language ID} will be used.
	 * @return CLocale the locale instance
	 */
	public function getLocale($localeID=null)
	{
		return CLocale::getInstance($localeID===null?$this->getLanguage():$localeID);
	}

	/**
	 * Returns the directory that contains the locale data.
	 * @return string the directory that contains the locale data. It defaults to 'framework/i18n/data'.
	 * @since 1.1.0
	 */
	public function getLocaleDataPath()
	{
		return CLocale::$dataPath===null ? Yii::getPathOfAlias('system.i18n.data') : CLocale::$dataPath;
	}

	/**
	 * Sets the directory that contains the locale data.
	 * @param string $value the directory that contains the locale data.
	 * @since 1.1.0
	 */
	public function setLocaleDataPath($value)
	{
		CLocale::$dataPath=$value;
	}

	/**
	 * @return CNumberFormatter the locale-dependent number formatter.
	 * The current {@link getLocale application locale} will be used.
	 */
	public function getNumberFormatter()
	{
		return $this->getLocale()->getNumberFormatter();
	}

	/**
	 * Returns the locale-dependent date formatter.
	 * @return CDateFormatter the locale-dependent date formatter.
	 * The current {@link getLocale application locale} will be used.
	 */
	public function getDateFormatter()
	{
		return $this->getLocale()->getDateFormatter();
	}

	/**
	 * Returns the database connection component.
	 * @return CDbConnection the database connection
	 */
	public function getDb()
	{
		return $this->getComponent('db');
	}

	/**
	 * Returns the error handler component.
	 * @return CErrorHandler the error handler application component.
	 */
	public function getErrorHandler()
	{
		return $this->getComponent('errorHandler');
	}

	/**
	 * Returns the security manager component.
	 * @return CSecurityManager the security manager application component.
	 */
	public function getSecurityManager()
	{
		return $this->getComponent('securityManager');
	}

	/**
	 * Returns the state persister component.
	 * @return CStatePersister the state persister application component.
	 */
	public function getStatePersister()
	{
		return $this->getComponent('statePersister');
	}

	/**
	 * Returns the cache component.
	 * @return CCache the cache application component. Null if the component is not enabled.
	 */
	public function getCache()
	{
		return $this->getComponent('cache');
	}

	/**
	 * Returns the core message translations component.
	 * @return CPhpMessageSource the core message translations
	 */
	public function getCoreMessages()
	{
		return $this->getComponent('coreMessages');
	}

	/**
	 * Returns the application message translations component.
	 * @return CMessageSource the application message translations
	 */
	public function getMessages()
	{
		return $this->getComponent('messages');
	}

	/**
	 * Returns the request component.
	 * @return CHttpRequest the request component
	 */
	public function getRequest()
	{
		return $this->getComponent('request');
	}

	/**
	 * Returns the URL manager component.
	 * @return CUrlManager the URL manager component
	 */
	public function getUrlManager()
	{
		return $this->getComponent('urlManager');
	}

	/**
	 * Returns a global value.
	 *
	 * A global value is one that is persistent across users sessions and requests.
	 * @param string $key the name of the value to be returned
	 * @param mixed $defaultValue the default value. If the named global value is not found, this will be returned instead.
	 * @return mixed the named global value
	 * @see setGlobalState
	 */
	public function getGlobalState($key,$defaultValue=null)
	{
		if($this->_globalState===null)
			$this->loadGlobalState();
		if(isset($this->_globalState[$key]))
			return $this->_globalState[$key];
		else
			return $defaultValue;
	}

	/**
	 * Sets a global value.
	 *
	 * A global value is one that is persistent across users sessions and requests.
	 * Make sure that the value is serializable and unserializable.
	 * @param string $key the name of the value to be saved
	 * @param mixed $value the global value to be saved. It must be serializable.
	 * @param mixed $defaultValue the default value. If the named global value is the same as this value, it will be cleared from the current storage.
	 * @see getGlobalState
	 */
	public function setGlobalState($key,$value,$defaultValue=null)
	{
		if($this->_globalState===null)
			$this->loadGlobalState();

		$changed=$this->_stateChanged;
		if($value===$defaultValue)
		{
			if(isset($this->_globalState[$key]))
			{
				unset($this->_globalState[$key]);
				$this->_stateChanged=true;
			}
		}
		else if(!isset($this->_globalState[$key]) || $this->_globalState[$key]!==$value)
		{
			$this->_globalState[$key]=$value;
			$this->_stateChanged=true;
		}

		if($this->_stateChanged!==$changed)
			$this->attachEventHandler('onEndRequest',array($this,'saveGlobalState'));
	}

	/**
	 * Clears a global value.
	 *
	 * The value cleared will no longer be available in this request and the following requests.
	 * @param string $key the name of the value to be cleared
	 */
	public function clearGlobalState($key)
	{
		$this->setGlobalState($key,true,true);
	}

	/**
	 * Loads the global state data from persistent storage.
	 * @see getStatePersister
	 * @throws CException if the state persister is not available
	 */
	public function loadGlobalState()
	{
		$persister=$this->getStatePersister();
		if(($this->_globalState=$persister->load())===null)
			$this->_globalState=array();
		$this->_stateChanged=false;
		$this->detachEventHandler('onEndRequest',array($this,'saveGlobalState'));
	}

	/**
	 * Saves the global state data into persistent storage.
	 * @see getStatePersister
	 * @throws CException if the state persister is not available
	 */
	public function saveGlobalState()
	{
		if($this->_stateChanged)
		{
			$this->_stateChanged=false;
			$this->detachEventHandler('onEndRequest',array($this,'saveGlobalState'));
			$this->getStatePersister()->save($this->_globalState);
		}
	}

	/**
	 * Handles uncaught PHP exceptions.
	 *
	 * This method is implemented as a PHP exception handler. It requires
	 * that constant YII_ENABLE_EXCEPTION_HANDLER be defined true.
	 *
	 * This method will first raise an {@link onException} event.
	 * If the exception is not handled by any event handler, it will call
	 * {@link getErrorHandler errorHandler} to process the exception.
	 *
	 * The application will be terminated by this method.
	 *
	 * @param Exception $exception exception that is not caught
	 */
	public function handleException($exception)
	{
		// disable error capturing to avoid recursive errors
		restore_error_handler();
		restore_exception_handler();

		$category='exception.'.get_class($exception);
		if($exception instanceof CHttpException)
			$category.='.'.$exception->statusCode;
		// php <5.2 doesn't support string conversion auto-magically
		$message=$exception->__toString();
		if(isset($_SERVER['REQUEST_URI']))
			$message.=' REQUEST_URI='.$_SERVER['REQUEST_URI'];
		Yii::log($message,CLogger::LEVEL_ERROR,$category);

		try
		{
			$event=new CExceptionEvent($this,$exception);
			$this->onException($event);
			if(!$event->handled)
			{
				// try an error handler
				if(($handler=$this->getErrorHandler())!==null)
					$handler->handle($event);
				else
					$this->displayException($exception);
			}
		}
		catch(Exception $e)
		{
			$this->displayException($e);
		}

		try
		{
			$this->end(1);
		}
		catch(Exception $e)
		{
			// use the most primitive way to log error
			$msg = get_class($e).': '.$e->getMessage().' ('.$e->getFile().':'.$e->getLine().")\n";
			$msg .= $e->getTraceAsString()."\n";
			$msg .= "Previous exception:\n";
			$msg .= get_class($exception).': '.$exception->getMessage().' ('.$exception->getFile().':'.$exception->getLine().")\n";
			$msg .= $exception->getTraceAsString()."\n";
			$msg .= '$_SERVER='.var_export($_SERVER,true);
			error_log($msg);
			exit(1);
		}
	}

	/**
	 * Handles PHP execution errors such as warnings, notices.
	 *
	 * This method is implemented as a PHP error handler. It requires
	 * that constant YII_ENABLE_ERROR_HANDLER be defined true.
	 *
	 * This method will first raise an {@link onError} event.
	 * If the error is not handled by any event handler, it will call
	 * {@link getErrorHandler errorHandler} to process the error.
	 *
	 * The application will be terminated by this method.
	 *
	 * @param integer $code the level of the error raised
	 * @param string $message the error message
	 * @param string $file the filename that the error was raised in
	 * @param integer $line the line number the error was raised at
	 */
	public function handleError($code,$message,$file,$line)
	{
		if($code & error_reporting())
		{
			// disable error capturing to avoid recursive errors
			restore_error_handler();
			restore_exception_handler();

			$log="$message ($file:$line)\nStack trace:\n";
			$trace=debug_backtrace();
			// skip the first 3 stacks as they do not tell the error position
			if(count($trace)>3)
				$trace=array_slice($trace,3);
			foreach($trace as $i=>$t)
			{
				if(!isset($t['file']))
					$t['file']='unknown';
				if(!isset($t['line']))
					$t['line']=0;
				if(!isset($t['function']))
					$t['function']='unknown';
				$log.="#$i {$t['file']}({$t['line']}): ";
				if(isset($t['object']) && is_object($t['object']))
					$log.=get_class($t['object']).'->';
				$log.="{$t['function']}()\n";
			}
			if(isset($_SERVER['REQUEST_URI']))
				$log.='REQUEST_URI='.$_SERVER['REQUEST_URI'];
			Yii::log($log,CLogger::LEVEL_ERROR,'php');

			try
			{
				Yii::import('CErrorEvent',true);
				$event=new CErrorEvent($this,$code,$message,$file,$line);
				$this->onError($event);
				if(!$event->handled)
				{
					// try an error handler
					if(($handler=$this->getErrorHandler())!==null)
						$handler->handle($event);
					else
						$this->displayError($code,$message,$file,$line);
				}
			}
			catch(Exception $e)
			{
				$this->displayException($e);
			}

			try
			{
				$this->end(1);
			}
			catch(Exception $e)
			{
				// use the most primitive way to log error
				$msg = get_class($e).': '.$e->getMessage().' ('.$e->getFile().':'.$e->getLine().")\n";
				$msg .= $e->getTraceAsString()."\n";
				$msg .= "Previous error:\n";
				$msg .= $log."\n";
				$msg .= '$_SERVER='.var_export($_SERVER,true);
				error_log($msg);
				exit(1);
			}
		}
	}

	/**
	 * Raised when an uncaught PHP exception occurs.
	 *
	 * An event handler can set the {@link CExceptionEvent::handled handled}
	 * property of the event parameter to be true to indicate no further error
	 * handling is needed. Otherwise, the {@link getErrorHandler errorHandler}
	 * application component will continue processing the error.
	 *
	 * @param CExceptionEvent $event event parameter
	 */
	public function onException($event)
	{
		$this->raiseEvent('onException',$event);
	}

	/**
	 * Raised when a PHP execution error occurs.
	 *
	 * An event handler can set the {@link CErrorEvent::handled handled}
	 * property of the event parameter to be true to indicate no further error
	 * handling is needed. Otherwise, the {@link getErrorHandler errorHandler}
	 * application component will continue processing the error.
	 *
	 * @param CErrorEvent $event event parameter
	 */
	public function onError($event)
	{
		$this->raiseEvent('onError',$event);
	}

	/**
	 * Displays the captured PHP error.
	 * This method displays the error in HTML when there is
	 * no active error handler.
	 * @param integer $code error code
	 * @param string $message error message
	 * @param string $file error file
	 * @param string $line error line
	 */
	public function displayError($code,$message,$file,$line)
	{
		if(YII_DEBUG)
		{
			echo "<h1>PHP Error [$code]</h1>\n";
			echo "<p>$message ($file:$line)</p>\n";
			echo '<pre>';

			$trace=debug_backtrace();
			// skip the first 3 stacks as they do not tell the error position
			if(count($trace)>3)
				$trace=array_slice($trace,3);
			foreach($trace as $i=>$t)
			{
				if(!isset($t['file']))
					$t['file']='unknown';
				if(!isset($t['line']))
					$t['line']=0;
				if(!isset($t['function']))
					$t['function']='unknown';
				echo "#$i {$t['file']}({$t['line']}): ";
				if(isset($t['object']) && is_object($t['object']))
					echo get_class($t['object']).'->';
				echo "{$t['function']}()\n";
			}

			echo '</pre>';
		}
		else
		{
			echo "<h1>PHP Error [$code]</h1>\n";
			echo "<p>$message</p>\n";
		}
	}

	/**
	 * Displays the uncaught PHP exception.
	 * This method displays the exception in HTML when there is
	 * no active error handler.
	 * @param Exception $exception the uncaught exception
	 */
	public function displayException($exception)
	{
		if(YII_DEBUG)
		{
			echo '<h1>'.get_class($exception)."</h1>\n";
			echo '<p>'.$exception->getMessage().' ('.$exception->getFile().':'.$exception->getLine().')</p>';
			echo '<pre>'.$exception->getTraceAsString().'</pre>';
		}
		else
		{
			echo '<h1>'.get_class($exception)."</h1>\n";
			echo '<p>'.$exception->getMessage().'</p>';
		}
	}

	/**
	 * Initializes the class autoloader and error handlers.
	 */
	protected function initSystemHandlers()
	{
		if(YII_ENABLE_EXCEPTION_HANDLER)
			set_exception_handler(array($this,'handleException'));
		if(YII_ENABLE_ERROR_HANDLER)
			set_error_handler(array($this,'handleError'),error_reporting());
	}

	/**
	 * Registers the core application components.
	 * @see setComponents
	 */
	protected function registerCoreComponents()
	{
		$components=array(
			'coreMessages'=>array(
				'class'=>'CPhpMessageSource',
				'language'=>'en_us',
				'basePath'=>YII_PATH.DIRECTORY_SEPARATOR.'messages',
			),
			'db'=>array(
				'class'=>'CDbConnection',
			),
			'messages'=>array(
				'class'=>'CPhpMessageSource',
			),
			'errorHandler'=>array(
				'class'=>'CErrorHandler',
			),
			'securityManager'=>array(
				'class'=>'CSecurityManager',
			),
			'statePersister'=>array(
				'class'=>'CStatePersister',
			),
			'urlManager'=>array(
				'class'=>'CUrlManager',
			),
			'request'=>array(
				'class'=>'CHttpRequest',
			),
			'format'=>array(
				'class'=>'CFormatter',
			),
		);

		$this->setComponents($components);
	}
}