diff --git a/framework/YiiBase.php b/framework/YiiBase.php
index 9d3698b..1230053 100644
--- a/framework/YiiBase.php
+++ b/framework/YiiBase.php
@@ -121,8 +121,8 @@ class YiiBase
 	 *
 	 * To import a class or a directory, one can use either path alias or class name (can be namespaced):
 	 *
-	 *  - `@app/components/GoogleMap`: importing the `GoogleMap` class with a path alias;
-	 *  - `@app/components/*`: importing the whole `components` directory with a path alias;
+	 *  - `@application/components/GoogleMap`: importing the `GoogleMap` class with a path alias;
+	 *  - `@application/components/*`: importing the whole `components` directory with a path alias;
 	 *  - `GoogleMap`: importing the `GoogleMap` class with a class name. [[autoload()]] will be used
 	 *  when this class is used for the first time.
 	 *
@@ -322,12 +322,12 @@ class YiiBase
 	 * the class. For example,
 	 *
 	 * - `\app\components\GoogleMap`: fully-qualified namespaced class.
-	 * - `@app/components/GoogleMap`: an alias
+	 * - `@application/components/GoogleMap`: an alias
 	 *
 	 * Below are some usage examples:
 	 *
 	 * ~~~
-	 * $object = \Yii::createObject('@app/components/GoogleMap');
+	 * $object = \Yii::createObject('@application/components/GoogleMap');
 	 * $object = \Yii::createObject(array(
 	 *     'class' => '\app\components\GoogleMap',
 	 *     'apiKey' => 'xyz',
diff --git a/framework/base/Application.php b/framework/base/Application.php
index c618faa..6203d11 100644
--- a/framework/base/Application.php
+++ b/framework/base/Application.php
@@ -10,8 +10,8 @@
 namespace yii\base;
 
 use Yii;
+use yii\util\FileHelper;
 use yii\base\InvalidCallException;
-use yii\util\StringHelper;
 
 /**
  * Application is the base class for all application classes.
@@ -37,7 +37,7 @@ use yii\util\StringHelper;
  *   Yii framework messages. This application component is dynamically loaded when needed.</li>
  * </ul>
  *
- * Application will undergo the following lifecycles when processing a user request:
+ * Application will undergo the following life cycles when processing a user request:
  * <ol>
  * <li>load application configuration;</li>
  * <li>set up class autoloader and error handling;</li>
@@ -50,28 +50,6 @@ use yii\util\StringHelper;
  * 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.
  *
- * @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 \yii\db\Connection $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 UrlManager $urlManager Returns the URL manager component.
- * @property string $baseUrl Returns the relative URL for the application
- * @property string $homeUrl the homepage URL
- *
  * @author Qiang Xue <qiang.xue@gmail.com>
  * @since 2.0
  */
@@ -134,7 +112,7 @@ class Application extends Module
 		$this->setBasePath($basePath);
 		$this->registerDefaultAliases();
 		$this->registerCoreComponents();
-		parent::__construct($id, $this, $config);
+		Component::__construct($config);
 	}
 
 	/**
@@ -204,27 +182,6 @@ class Application extends Module
 	}
 
 	/**
-	 * Runs a controller with the given route and parameters.
-	 * @param string $route the route (e.g. `post/create`)
-	 * @param array $params the parameters to be passed to the controller action
-	 * @return integer the exit status (0 means normal, non-zero values mean abnormal)
-	 * @throws InvalidRequestException if the route cannot be resolved into a controller
-	 */
-	public function runController($route, $params = array())
-	{
-		$result = $this->createController($route);
-		if ($result === false) {
-			throw new InvalidRequestException(Yii::t('yii', 'Unable to resolve the request.'));
-		}
-
-		$priorController = $this->controller;
-		$this->controller = $controllerObject;
-		$status = $controllerObject->run($action, $params);
-		$this->controller = $priorController;
-		return $status;
-	}
-
-	/**
 	 * Returns the directory that stores runtime files.
 	 * @return string the directory that stores runtime files. Defaults to 'protected/runtime'.
 	 */
@@ -239,15 +196,15 @@ class Application extends Module
 	/**
 	 * Sets the directory that stores runtime files.
 	 * @param string $path the directory that stores runtime files.
-	 * @throws InvalidCallException if the directory does not exist or is not writable
+	 * @throws InvalidConfigException if the directory does not exist or is not writable
 	 */
 	public function setRuntimePath($path)
 	{
-		$p = Yii::getAlias($path);
-		if ($p === false || !is_dir($p) || !is_writable($path)) {
-			throw new InvalidCallException("Application runtime path \"$path\" is invalid. Please make sure it is a directory writable by the Web server process.");
-		} else {
+		$p = FileHelper::ensureDirectory($path);
+		if (is_writable($p)) {
 			$this->_runtimePath = $p;
+		} else {
+			throw new InvalidConfigException("Runtime path must be writable by the Web server process: $path");
 		}
 	}
 
@@ -296,34 +253,61 @@ class Application extends Module
 		date_default_timezone_set($value);
 	}
 
-	/**
-	 * 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);
-	}
-
-	/**
-	 * @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 security manager component.
+//	 * @return SecurityManager the security manager application component.
+//	 */
+//	public function getSecurityManager()
+//	{
+//		return $this->getComponent('securityManager');
+//	}
+//
+//	/**
+//	 * 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);
+//	}
+//
+//	/**
+//	 * @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 core message translations component.
+//	 * @return \yii\i18n\MessageSource the core message translations
+//	 */
+//	public function getCoreMessages()
+//	{
+//		return $this->getComponent('coreMessages');
+//	}
+//
+//	/**
+//	 * Returns the application message translations component.
+//	 * @return \yii\i18n\MessageSource the application message translations
+//	 */
+//	public function getMessages()
+//	{
+//		return $this->getComponent('messages');
+//	}
 
 	/**
 	 * Returns the database connection component.
@@ -353,15 +337,6 @@ class Application extends Module
 	}
 
 	/**
-	 * Returns the security manager component.
-	 * @return SecurityManager the security manager application component.
-	 */
-	public function getSecurityManager()
-	{
-		return $this->getComponent('securityManager');
-	}
-
-	/**
 	 * Returns the cache component.
 	 * @return \yii\caching\Cache the cache application component. Null if the component is not enabled.
 	 */
@@ -371,24 +346,6 @@ class Application extends Module
 	}
 
 	/**
-	 * Returns the core message translations component.
-	 * @return \yii\i18n\MessageSource the core message translations
-	 */
-	public function getCoreMessages()
-	{
-		return $this->getComponent('coreMessages');
-	}
-
-	/**
-	 * Returns the application message translations component.
-	 * @return \yii\i18n\MessageSource the application message translations
-	 */
-	public function getMessages()
-	{
-		return $this->getComponent('messages');
-	}
-
-	/**
 	 * Returns the request component.
 	 * @return Request the request component
 	 */
@@ -417,15 +374,6 @@ class Application extends Module
 			'errorHandler' => array(
 				'class' => 'yii\base\ErrorHandler',
 			),
-			'request' => array(
-				'class' => 'yii\base\Request',
-			),
-			'response' => array(
-				'class' => 'yii\base\Response',
-			),
-			'format' => array(
-				'class' => 'yii\base\Formatter',
-			),
 			'coreMessages' => array(
 				'class' => 'yii\i18n\PhpMessageSource',
 				'language' => 'en_us',
@@ -442,117 +390,4 @@ class Application extends Module
 			),
 		));
 	}
-
-	/**
-	 * Performs a controller action specified by a route.
-	 * This method parses the specified route and creates the corresponding controller and action
-	 * instances under the context of the specified module. It then runs the created action
-	 * with the given parameters.
-	 * @param string $route the route that specifies the action.
-	 * @param array $params the parameters to be passed to the action
-	 * @param Module $module the module which serves as the context of the route
-	 * @return integer the action
-	 * @throws InvalidConfigException if the module's defaultRoute is empty or the controller's defaultAction is empty
-	 * @throws InvalidRequestException if the requested route cannot be resolved into an action successfully
-	 */
-	public function runAction($route, $params = array(), $module = null)
-	{
-		if ($module === null) {
-			$module = $this;
-		}
-		$route = trim($route, '/');
-		if ($route === '') {
-			$route = trim($module->defaultRoute, '/');
-			if ($route == '') {
-				throw new InvalidConfigException(get_class($module) . '::defaultRoute cannot be empty.');
-			}
-		}
-		if (($pos = strpos($route, '/')) !== false) {
-			$id = substr($route, 0, $pos);
-			$route = substr($route, $pos + 1);
-		} else {
-			$id = $route;
-			$route = '';
-		}
-
-		$childModule = $module->getModule($id);
-		if ($childModule !== null) {
-			return $this->runAction($route, $params, $childModule);
-		}
-
-		$controller = $this->createController($id, $module);
-		if ($controller !== null) {
-			if ($route === '') {
-				$route = $controller->defaultAction;
-				if ($route == '') {
-					throw new InvalidConfigException(get_class($controller) . '::defaultAction cannot be empty.');
-				}
-			}
-
-			$action = $this->createAction($route, $controller);
-			if ($action !== null) {
-				return $action->runWithParams($params);
-			}
-		}
-
-		throw new InvalidRequestException("Unable to resolve the request: $route");
-	}
-
-
-	/**
-	 * Creates a controller instance based on the controller ID.
-	 *
-	 * The controller is created within the given module. The method first attempts to
-	 * create the controller based on the [[controllerMap]] of the module. If not available,
-	 * it will look for the controller class under the [[controllerPath]] and create an
-	 * instance of it.
-	 *
-	 * @param string $id the controller ID
-	 * @param Module $module the module that owns the controller
-	 * @return Controller the newly created controller instance
-	 */
-	public function createController($id, $module)
-	{
-		if (isset($module->controllerMap[$id])) {
-			return Yii::createObject($module->controllerMap[$id], $id, $module);
-		} elseif (preg_match('/^[a-z0-9\\-_]+$/', $id)) {
-			$className = StringHelper::id2camel($id) . 'Controller';
-			$classFile = $module->controllerPath . DIRECTORY_SEPARATOR . $className . '.php';
-			if (is_file($classFile)) {
-				$className = $module->controllerNamespace . '\\' . $className;
-				if (!class_exists($className, false)) {
-					require($classFile);
-				}
-				if (class_exists($className, false) && is_subclass_of($className, '\yii\base\Controller')) {
-					return new $className($id, $module);
-				}
-			}
-		}
-		return null;
-	}
-
-	/**
-	 * Creates an action based on the given action ID.
-	 * The action is created within the given controller. The method first attempts to
-	 * create the action based on [[Controller::actions()]]. If not available,
-	 * it will look for the inline action method within the controller.
-	 * @param string $id the action ID
-	 * @param Controller $controller the controller that owns the action
-	 * @return Action the newly created action instance
-	 */
-	public function createAction($id, $controller)
-	{
-		if (isset($controller->actionMap[$id])) {
-			return Yii::createObject($controller->actionMap[$id], $id, $controller);
-		} elseif (preg_match('/^[a-z0-9\\-_]+$/', $id)) {
-			$methodName = 'action' . StringHelper::id2camel($id);
-			if (method_exists($controller, $methodName)) {
-				$method = new \ReflectionMethod($controller, $methodName);
-				if ($method->getName() === $methodName) {
-					return new InlineAction($id, $controller);
-				}
-			}
-		}
-		return null;
-	}
 }
diff --git a/framework/base/Controller.php b/framework/base/Controller.php
index d62cc35..79ad574 100644
--- a/framework/base/Controller.php
+++ b/framework/base/Controller.php
@@ -9,6 +9,9 @@
 
 namespace yii\base;
 
+use Yii;
+use yii\util\StringHelper;
+
 /**
  * Controller is the base class for classes containing controller logic.
  *
@@ -27,6 +30,10 @@ namespace yii\base;
  */
 class Controller extends Component
 {
+	const EVENT_AUTHORIZE = 'authorize';
+	const EVENT_BEFORE_ACTION = 'beforeAction';
+	const EVENT_AFTER_ACTION = 'afterAction';
+
 	/**
 	 * @var string the ID of this controller
 	 */
@@ -91,65 +98,138 @@ class Controller extends Component
 	}
 
 	/**
-	 * Runs the controller with the specified action and parameters.
-	 * @param Action|string $action the action to be executed. This can be either an action object
-	 * or the ID of the action.
+	 * Runs an action with the specified action ID and parameters.
+	 * If the action ID is empty, the method will use [[defaultAction]].
+	 * @param string $id the ID of the action to be executed.
 	 * @param array $params the parameters (name-value pairs) to be passed to the action.
-	 * If null, the result of [[getActionParams()]] will be used as action parameters.
-	 * @return integer the exit status of the action. 0 means normal, other values mean abnormal.
-	 * @see missingAction
+	 * @return integer the status of the action execution. 0 means normal, other values mean abnormal.
+	 * @throws InvalidRouteException if the requested action ID cannot be resolved into an action successfully.
 	 * @see createAction
 	 */
-	public function run($action, $params = null)
+	public function runAction($id, $params = array())
 	{
-		if (is_string($action)) {
-			if (($a = $this->createAction($action)) !== null) {
-				$action = $a;
-			} else {
-				$this->missingAction($action);
-				return 1;
-			}
+		if ($id === '') {
+			$id = $this->defaultAction;
 		}
 
-		$priorAction = $this->action;
-		$this->action = $action;
+		$action = $this->createAction($id);
+		if ($action !== null) {
+			$oldAction = $this->action;
+			$this->action = $action;
 
-		if ($this->authorize($action) && $this->beforeAction($action)) {
-			if ($params === null) {
-				$params = $this->getActionParams();
+			if ($this->authorize($action) && $this->beforeAction($action)) {
+				$status = $action->runWithParams($params);
+				$this->afterAction($action);
+			} else {
+				$status = 1;
 			}
-			$status = $action->runWithParams($params);
-			$this->afterAction($action);
+
+			$this->action = $oldAction;
+
+			return $status;
 		} else {
-			$status = 1;
+			throw new InvalidRouteException('Unable to resolve the request: ' . $this->getUniqueId() . '/' . $id);
 		}
+	}
 
-		$this->action = $priorAction;
+	/**
+	 * Runs a request specified in terms of a route.
+	 * The route can be either an ID of an action within this controller or a complete route consisting
+	 * of module IDs, controller ID and action ID. If the route starts with a slash '/', the parsing of
+	 * the route will start from the application; otherwise, it will start from the parent module of this controller.
+	 * @param string $route the route to be handled, e.g., 'view', 'comment/view', '/admin/comment/view'.
+	 * @param array $params the parameters to be passed to the action.
+	 * @return integer the status code returned by the action execution. 0 means normal, and other values mean abnormal.
+	 * @see runAction
+	 * @see forward
+	 */
+	public function run($route, $params = array())
+	{
+		$pos = strpos($route, '/');
+		if ($pos === false) {
+			return $this->runAction($route, $params);
+		} elseif ($pos > 0) {
+			return $this->module->runAction($route, $params);
+		} else {
+			return \Yii::$application->runAction($route, $params);
+		}
+	}
 
-		return $status;
+	/**
+	 * Forwards the current execution flow to handle a new request specified by a route.
+	 * The only difference between this method and [[run()]] is that after calling this method,
+	 * the application will exit.
+	 * @param string $route the route to be handled, e.g., 'view', 'comment/view', '/admin/comment/view'.
+	 * @param array $params the parameters to be passed to the action.
+	 * @return integer the status code returned by the action execution. 0 means normal, and other values mean abnormal.
+	 * @see run
+	 */
+	public function forward($route, $params = array())
+	{
+		$status = $this->run($route, $params);
+		exit($status);
 	}
 
 	/**
-	 * Creates the action instance based on the action ID.
-	 * The action can be either an inline action or an object.
-	 * The latter is created by looking up the action map specified in [[actions]].
-	 * @param string $actionID ID of the action. If empty, it will take the value of [[defaultAction]].
-	 * @return Action the action instance, null if the action does not exist.
-	 * @see actions
+	 * Creates an action based on the given action ID.
+	 * The method first checks if the action ID has been declared in [[actions()]]. If so,
+	 * it will use the configuration declared there to create the action object.
+	 * If not, it will look for a controller method whose name is in the format of `actionXyz`
+	 * where `Xyz` stands for the action ID. If found, an [[InlineAction]] representing that
+	 * method will be created and returned.
+	 * @param string $id the action ID
+	 * @return Action the newly created action instance. Null if the ID doesn't resolve into any action.
 	 */
-	public function createAction($actionID)
+	public function createAction($id)
 	{
-		if ($actionID === '') {
-			$actionID = $this->defaultAction;
-		}
-		$actions = $this->actions();
-		if (isset($actions[$actionID])) {
-			return \Yii::createObject($actions[$actionID], $actionID, $this);
-		} elseif (method_exists($this, 'action' . $actionID)) {
-			return new InlineAction($actionID, $this);
-		} else {
-			return null;
+		$actionMap = $this->actions();
+		if (isset($actionMap[$id])) {
+			return Yii::createObject($actionMap[$id], $id, $this);
+		} elseif (preg_match('/^[a-z0-9\\-_]+$/', $id)) {
+			$methodName = 'action' . StringHelper::id2camel($id);
+			if (method_exists($this, $methodName)) {
+				$method = new \ReflectionMethod($this, $methodName);
+				if ($method->getName() === $methodName) {
+					return new InlineAction($id, $this);
+				}
+			}
 		}
+		return null;
+	}
+
+	/**
+	 * This method is invoked when checking the access for the action to be executed.
+	 * @param Action $action the action to be executed.
+	 * @return boolean whether the action is allowed to be executed.
+	 */
+	public function authorize($action)
+	{
+		$event = new ActionEvent($action);
+		$this->trigger(self::EVENT_AUTHORIZE, $event);
+		return $event->isValid;
+	}
+
+	/**
+	 * This method is invoked right before an action is to be executed (after all possible filters.)
+	 * You may override this method to do last-minute preparation for the action.
+	 * @param Action $action the action to be executed.
+	 * @return boolean whether the action should continue to be executed.
+	 */
+	public function beforeAction($action)
+	{
+		$event = new ActionEvent($action);
+		$this->trigger(self::EVENT_BEFORE_ACTION, $event);
+		return $event->isValid;
+	}
+
+	/**
+	 * This method is invoked right after an action is executed.
+	 * You may override this method to do some postprocessing for the action.
+	 * @param Action $action the action just executed.
+	 */
+	public function afterAction($action)
+	{
+		$this->trigger(self::EVENT_AFTER_ACTION, new ActionEvent($action));
 	}
 
 	/**
@@ -217,67 +297,6 @@ class Controller extends Component
 		return $this->action !== null ? $this->getUniqueId() . '/' . $this->action->id : $this->getUniqueId();
 	}
 
-	/**
-	 * Processes the request using another controller action.
-	 * @param string $route the route of the new controller action. This can be an action ID, or a complete route
-	 * with module ID (optional in the current module), controller ID and action ID. If the former,
-	 * the action is assumed to be located within the current controller.
-	 * @param array $params the parameters to be passed to the action.
-	 * If null, the result of [[getActionParams()]] will be used as action parameters.
-	 * Note that the parameters must be name-value pairs with the names corresponding to
-	 * the parameter names as declared by the action.
-	 * @param boolean $exit whether to end the application after this call. Defaults to true.
-	 */
-	public function forward($route, $params = array(), $exit = true)
-	{
-		if (strpos($route, '/') === false) {
-			$status = $this->run($route, $params);
-		} else {
-			if ($route[0] !== '/' && !$this->module instanceof Application) {
-				$route = '/' . $this->module->getUniqueId() . '/' . $route;
-			}
-			$status = \Yii::$application->runController($route, $params);
-		}
-		if ($exit) {
-			\Yii::$application->end($status);
-		}
-	}
-
-	/**
-	 * This method is invoked when checking the access for the action to be executed.
-	 * @param Action $action the action to be executed.
-	 * @return boolean whether the action is allowed to be executed.
-	 */
-	public function authorize($action)
-	{
-		$event = new ActionEvent($action);
-		$this->trigger(__METHOD__, $event);
-		return $event->isValid;
-	}
-
-	/**
-	 * This method is invoked right before an action is to be executed (after all possible filters.)
-	 * You may override this method to do last-minute preparation for the action.
-	 * @param Action $action the action to be executed.
-	 * @return boolean whether the action should continue to be executed.
-	 */
-	public function beforeAction($action)
-	{
-		$event = new ActionEvent($action);
-		$this->trigger(__METHOD__, $event);
-		return $event->isValid;
-	}
-
-	/**
-	 * This method is invoked right after an action is executed.
-	 * You may override this method to do some postprocessing for the action.
-	 * @param Action $action the action just executed.
-	 */
-	public function afterAction($action)
-	{
-		$this->trigger(__METHOD__, new ActionEvent($action));
-	}
-
 	public function render($view, $params = array())
 	{
 		return $this->createView()->render($view, $params);
diff --git a/framework/base/InvalidRouteException.php b/framework/base/InvalidRouteException.php
new file mode 100644
index 0000000..8e82b40
--- /dev/null
+++ b/framework/base/InvalidRouteException.php
@@ -0,0 +1,21 @@
+<?php
+/**
+ * InvalidRouteException class file.
+ *
+ * @link http://www.yiiframework.com/
+ * @copyright Copyright &copy; 2008 Yii Software LLC
+ * @license http://www.yiiframework.com/license/
+ */
+
+namespace yii\base;
+
+/**
+ * InvalidRouteException represents an exception caused by an invalid route.
+ *
+ * @author Qiang Xue <qiang.xue@gmail.com>
+ * @since 2.0
+ */
+class InvalidRouteException extends \Exception
+{
+}
+
diff --git a/framework/base/Module.php b/framework/base/Module.php
index 0539cdc..23bd577 100644
--- a/framework/base/Module.php
+++ b/framework/base/Module.php
@@ -16,13 +16,19 @@ use yii\util\FileHelper;
 /**
  * Module is the base class for module and application classes.
  *
- * Module mainly manages application components and sub-modules that belongs to a module.
+ * A module represents a sub-application which contains MVC elements by itself, such as
+ * models, views, controllers, etc.
+ *
+ * A module may consist of [[modules|sub-modules]].
+ *
+ * [[components|Components]] may be registered with the module so that they are globally
+ * accessible within the module.
  *
  * @property string $uniqueId An ID that uniquely identifies this module among all modules within
  * the current application.
  * @property string $basePath The root directory of the module. Defaults to the directory containing the module class.
  * @property array $modules The configuration of the currently installed modules (module ID => configuration).
- * @property array $components The application components (indexed by their IDs).
+ * @property array $components The components (indexed by their IDs) registered within this module.
  * @property array $import List of aliases to be imported. This property is write-only.
  * @property array $aliases List of aliases to be defined. This property is write-only.
  *
@@ -36,7 +42,7 @@ abstract class Module extends Component
 	 */
 	public $params = array();
 	/**
-	 * @var array the IDs of the application components that should be preloaded when this module is created.
+	 * @var array the IDs of the components that should be preloaded when this module is created.
 	 */
 	public $preload = array();
 	/**
@@ -88,27 +94,27 @@ abstract class Module extends Component
 	/**
 	 * @var string the root directory of the module.
 	 */
-	protected $_basePath;
+	private $_basePath;
 	/**
 	 * @var string the root directory that contains view files for this module
 	 */
-	protected $_viewPath;
+	private $_viewPath;
 	/**
 	 * @var string the root directory that contains layout view files for this module.
 	 */
-	protected $_layoutPath;
+	private $_layoutPath;
 	/**
 	 * @var string the directory containing controller classes in the module.
 	 */
-	protected $_controllerPath;
+	private $_controllerPath;
 	/**
 	 * @var array child modules of this module
 	 */
-	protected $_modules = array();
+	private $_modules = array();
 	/**
-	 * @var array application components of this module
+	 * @var array components registered under this module
 	 */
-	protected $_components = array();
+	private $_components = array();
 
 	/**
 	 * Constructor.
@@ -125,9 +131,9 @@ abstract class Module extends Component
 
 	/**
 	 * Getter magic method.
-	 * This method is overridden to support accessing application components
+	 * This method is overridden to support accessing components
 	 * like reading module properties.
-	 * @param string $name application component or property name
+	 * @param string $name component or property name
 	 * @return mixed the named property value
 	 */
 	public function __get($name)
@@ -142,7 +148,7 @@ abstract class Module extends Component
 	/**
 	 * Checks if a property value is null.
 	 * This method overrides the parent implementation by checking
-	 * if the named application component is loaded.
+	 * if the named component is loaded.
 	 * @param string $name the property name or the event name
 	 * @return boolean whether the property value is null
 	 */
@@ -163,7 +169,7 @@ abstract class Module extends Component
 	 */
 	public function init()
 	{
-		\Yii::setAlias('@' . $this->id, $this->getBasePath());
+		Yii::setAlias('@' . $this->id, $this->getBasePath());
 		$this->preloadComponents();
 	}
 
@@ -282,19 +288,19 @@ abstract class Module extends Component
 	/**
 	 * Imports the specified path aliases.
 	 * This method is provided so that you can import a set of path aliases when configuring a module.
-	 * The path aliases will be imported by calling [[\Yii::import()]].
+	 * The path aliases will be imported by calling [[Yii::import()]].
 	 * @param array $aliases list of path aliases to be imported
 	 */
 	public function setImport($aliases)
 	{
 		foreach ($aliases as $alias) {
-			\Yii::import($alias);
+			Yii::import($alias);
 		}
 	}
 
 	/**
 	 * Defines path aliases.
-	 * This method calls [[\Yii::setAlias()]] to register the path aliases.
+	 * This method calls [[Yii::setAlias()]] to register the path aliases.
 	 * This method is provided so that you can define path aliases when configuring a module.
 	 * @param array $aliases list of path aliases to be defined. The array keys are alias names
 	 * (must start with '@') and the array values are the corresponding paths or aliases.
@@ -302,7 +308,7 @@ abstract class Module extends Component
 	 *
 	 * ~~~
 	 * array(
-	 *	'@models' => '@app/models', // an existing alias
+	 *	'@models' => '@application/models', // an existing alias
 	 *	'@backend' => __DIR__ . '/../backend',  // a directory
 	 * )
 	 * ~~~
@@ -310,7 +316,7 @@ abstract class Module extends Component
 	public function setAliases($aliases)
 	{
 		foreach ($aliases as $name => $alias) {
-			\Yii::setAlias($name, $alias);
+			Yii::setAlias($name, $alias);
 		}
 	}
 
@@ -339,8 +345,8 @@ abstract class Module extends Component
 			if ($this->_modules[$id] instanceof Module) {
 				return $this->_modules[$id];
 			} elseif ($load) {
-				\Yii::trace("Loading \"$id\" module", __CLASS__);
-				return $this->_modules[$id] = \Yii::createObject($this->_modules[$id], $id, $this);
+				Yii::trace("Loading module: $id", __CLASS__);
+				return $this->_modules[$id] = Yii::createObject($this->_modules[$id], $id, $this);
 			}
 		}
 		return null;
@@ -393,7 +399,7 @@ abstract class Module extends Component
 	 *
 	 * Each sub-module should be specified as a name-value pair, where
 	 * name refers to the ID of the module and value the module or a configuration
-	 * array that can be used to create the module. In the latter case, [[\Yii::createObject()]]
+	 * array that can be used to create the module. In the latter case, [[Yii::createObject()]]
 	 * will be used to create the module.
 	 *
 	 * If a new sub-module has the same ID as an existing one, the existing one will be overwritten silently.
@@ -423,8 +429,8 @@ abstract class Module extends Component
 
 	/**
 	 * Checks whether the named component exists.
-	 * @param string $id application component ID
-	 * @return boolean whether the named application component exists. Both loaded and unloaded components
+	 * @param string $id component ID
+	 * @return boolean whether the named component exists. Both loaded and unloaded components
 	 * are considered.
 	 */
 	public function hasComponent($id)
@@ -433,11 +439,10 @@ abstract class Module extends Component
 	}
 
 	/**
-	 * Retrieves the named application component.
-	 * @param string $id application component ID (case-sensitive)
+	 * Retrieves the named component.
+	 * @param string $id component ID (case-sensitive)
 	 * @param boolean $load whether to load the component if it is not yet loaded.
-	 * @return Component|null the application component instance, null if the application component
-	 * does not exist.
+	 * @return Component|null the component instance, null if the component does not exist.
 	 * @see hasComponent()
 	 */
 	public function getComponent($id, $load = true)
@@ -446,22 +451,22 @@ abstract class Module extends Component
 			if ($this->_components[$id] instanceof Component) {
 				return $this->_components[$id];
 			} elseif ($load) {
-				\Yii::trace("Loading \"$id\" application component", __CLASS__);
-				return $this->_components[$id] = \Yii::createObject($this->_components[$id]);
+				Yii::trace("Loading component: $id", __CLASS__);
+				return $this->_components[$id] = Yii::createObject($this->_components[$id]);
 			}
 		}
 		return null;
 	}
 
 	/**
-	 * Registers an application component in this module.
+	 * Registers a component with this module.
 	 * @param string $id component ID
-	 * @param Component|array|null $component the component to be added to the module. This can
+	 * @param Component|array|null $component the component to be registered with the module. This can
 	 * be one of the followings:
 	 *
 	 * - a [[Component]] object
 	 * - a configuration array: when [[getComponent()]] is called initially for this component, the array
-	 *   will be used to instantiate the component
+	 *   will be used to instantiate the component via [[Yii::createObject()]].
 	 * - null: the named component will be removed from the module
 	 */
 	public function setComponent($id, $component)
@@ -474,11 +479,11 @@ abstract class Module extends Component
 	}
 
 	/**
-	 * Returns the application components.
+	 * Returns the registered components.
 	 * @param boolean $loadedOnly whether to return the loaded components only. If this is set false,
 	 * then all components specified in the configuration will be returned, whether they are loaded or not.
 	 * Loaded components will be returned as objects, while unloaded components as configuration arrays.
-	 * @return array the application components (indexed by their IDs)
+	 * @return array the components (indexed by their IDs)
 	 */
 	public function getComponents($loadedOnly = false)
 	{
@@ -496,11 +501,11 @@ abstract class Module extends Component
 	}
 
 	/**
-	 * Registers a set of application components in this module.
+	 * Registers a set of components in this module.
 	 *
-	 * Each application component should be specified as a name-value pair, where
+	 * Each component should be specified as a name-value pair, where
 	 * name refers to the ID of the component and value the component or a configuration
-	 * array that can be used to create the component. In the latter case, [[\Yii::createObject()]]
+	 * array that can be used to create the component. In the latter case, [[Yii::createObject()]]
 	 * will be used to create the component.
 	 *
 	 * If a new component has the same ID as an existing one, the existing one will be overwritten silently.
@@ -520,7 +525,7 @@ abstract class Module extends Component
 	 * )
 	 * ~~~
 	 *
-	 * @param array $components application components (id => component configuration or instance)
+	 * @param array $components components (id => component configuration or instance)
 	 */
 	public function setComponents($components)
 	{
@@ -530,7 +535,7 @@ abstract class Module extends Component
 	}
 
 	/**
-	 * Loads application components that are declared in [[preload]].
+	 * Loads components that are declared in [[preload]].
 	 */
 	public function preloadComponents()
 	{
@@ -540,54 +545,47 @@ abstract class Module extends Component
 	}
 
 	/**
-	 * Performs a controller action specified by a route.
-	 * This method parses the specified route and creates the corresponding controller and action
-	 * instances under the context of the specified module. It then runs the created action
-	 * with the given parameters.
+	 * Runs a controller action specified by a route.
+	 * This method parses the specified route and creates the corresponding child module(s), controller and action
+	 * instances. It then calls [[Controller::runAction()]] to run the action with the given parameters.
+	 * If the route is empty, the method will use [[defaultRoute]].
 	 * @param string $route the route that specifies the action.
 	 * @param array $params the parameters to be passed to the action
-	 * @return integer the action
-	 * @throws InvalidConfigException if the module's defaultRoute is empty or the controller's defaultAction is empty
-	 * @throws InvalidRequestException if the requested route cannot be resolved into an action successfully
+	 * @return integer the status code returned by the action execution. 0 means normal, and other values mean abnormal.
+	 * @throws InvalidRouteException if the requested route cannot be resolved into an action successfully
 	 */
 	public function runAction($route, $params = array())
 	{
 		$route = trim($route, '/');
 		if ($route === '') {
 			$route = trim($this->defaultRoute, '/');
-			if ($route == '') {
-				throw new InvalidConfigException(get_class($this) . '::defaultRoute cannot be empty.');
-			}
 		}
 		if (($pos = strpos($route, '/')) !== false) {
 			$id = substr($route, 0, $pos);
-			$route = substr($route, $pos + 1);
+			$route2 = substr($route, $pos + 1);
 		} else {
 			$id = $route;
-			$route = '';
+			$route2 = '';
 		}
 
 		$module = $this->getModule($id);
 		if ($module !== null) {
-			return $module->runAction($route, $params);
+			return $module->runAction($route2, $params);
 		}
 
 		$controller = $this->createController($id);
 		if ($controller !== null) {
-			if ($route === '') {
-				$route = $controller->defaultAction;
-				if ($route == '') {
-					throw new InvalidConfigException(get_class($controller) . '::defaultAction cannot be empty.');
-				}
-			}
+			$oldController = Yii::$application->controller;
+			Yii::$application->controller = $controller;
 
-			$action = $controller->createAction($route);
-			if ($action !== null) {
-				return $action->runWithParams($params);
-			}
-		}
+			$status = $controller->runAction($route2, $params);
 
-		throw new InvalidRequestException('Unable to resolve the request: ' . ltrim($this->getUniqueId() . '/' . $route, '/'));
+			Yii::$application->controller = $oldController;
+
+			return $status;
+		} else {
+			throw new InvalidRouteException('Unable to resolve the request: ' . $this->getUniqueId() . '/' . $route);
+		}
 	}
 
 	/**
diff --git a/framework/base/View.php b/framework/base/View.php
index db0741a..9657025 100644
--- a/framework/base/View.php
+++ b/framework/base/View.php
@@ -97,7 +97,7 @@ class View extends Component
 	 * To determine which view file should be rendered, the method calls [[findViewFile()]] which
 	 * will search in the directories as specified by [[basePath]].
 	 *
-	 * View name can be a path alias representing an absolute file path (e.g. `@app/views/layout/index`),
+	 * View name can be a path alias representing an absolute file path (e.g. `@application/views/layout/index`),
 	 * or a path relative to [[basePath]]. The file suffix is optional and defaults to `.php` if not given
 	 * in the view name.
 	 *
diff --git a/framework/base/Widget.php b/framework/base/Widget.php
index 3608205..686e58e 100644
--- a/framework/base/Widget.php
+++ b/framework/base/Widget.php
@@ -80,7 +80,7 @@ class Widget extends Component
 	 * To determine which view file should be rendered, the method calls [[findViewFile()]] which
 	 * will search in the directories as specified by [[basePath]].
 	 *
-	 * View name can be a path alias representing an absolute file path (e.g. `@app/views/layout/index`),
+	 * View name can be a path alias representing an absolute file path (e.g. `@application/views/layout/index`),
 	 * or a path relative to [[basePath]]. The file suffix is optional and defaults to `.php` if not given
 	 * in the view name.
 	 *
diff --git a/framework/logging/DbTarget.php b/framework/logging/DbTarget.php
index 004bf21..129e4d4 100644
--- a/framework/logging/DbTarget.php
+++ b/framework/logging/DbTarget.php
@@ -89,16 +89,17 @@ class DbTarget extends Target
 	}
 
 	/**
-	 * Stores log [[messages]] to DB.
-	 * @param boolean $final whether this method is called at the end of the current application
+	 * Stores log messages to DB.
+	 * @param array $messages the messages to be exported. See [[Logger::messages]] for the structure
+	 * of each message.
 	 */
-	public function exportMessages($final)
+	public function export($messages)
 	{
 		$db = $this->getDb();
 		$tableName = $db->quoteTableName($this->tableName);
 		$sql = "INSERT INTO $tableName (level, category, log_time, message) VALUES (:level, :category, :log_time, :message)";
 		$command = $db->createCommand($sql);
-		foreach ($this->messages as $message) {
+		foreach ($messages as $message) {
 			$command->bindValues(array(
 				':level' => $message[1],
 				':category' => $message[2],
diff --git a/framework/logging/EmailTarget.php b/framework/logging/EmailTarget.php
index 73fd3bb..e02e4da 100644
--- a/framework/logging/EmailTarget.php
+++ b/framework/logging/EmailTarget.php
@@ -39,13 +39,14 @@ class EmailTarget extends Target
 	public $headers = array();
 
 	/**
-	 * Sends log [[messages]] to specified email addresses.
-	 * @param boolean $final whether this method is called at the end of the current application
+	 * Sends log messages to specified email addresses.
+	 * @param array $messages the messages to be exported. See [[Logger::messages]] for the structure
+	 * of each message.
 	 */
-	public function exportMessages($final)
+	public function export($messages)
 	{
 		$body = '';
-		foreach ($this->messages as $message) {
+		foreach ($messages as $message) {
 			$body .= $this->formatMessage($message);
 		}
 		$body = wordwrap($body, 70);
diff --git a/framework/logging/FileTarget.php b/framework/logging/FileTarget.php
index f4ddf44..0eb897e 100644
--- a/framework/logging/FileTarget.php
+++ b/framework/logging/FileTarget.php
@@ -65,19 +65,28 @@ class FileTarget extends Target
 	}
 
 	/**
-	 * Sends log [[messages]] to specified email addresses.
-	 * @param boolean $final whether this method is called at the end of the current application
+	 * Sends log messages to specified email addresses.
+	 * @param array $messages the messages to be exported. See [[Logger::messages]] for the structure
+	 * of each message.
 	 */
-	public function exportMessages($final)
+	public function export($messages)
 	{
+		$text = '';
+		foreach ($messages as $message) {
+			$text .= $this->formatMessage($message);
+		}
+		$fp = @fopen($this->logFile, 'a');
+		@flock($fp, LOCK_EX);
 		if (@filesize($this->logFile) > $this->maxFileSize * 1024) {
 			$this->rotateFiles();
+			@flock($fp,LOCK_UN);
+			@fclose($fp);
+			@file_put_contents($this->logFile, $text, FILE_APPEND | LOCK_EX);
+		} else {
+			@fwrite($fp, $text);
+			@flock($fp,LOCK_UN);
+			@fclose($fp);
 		}
-		$messages = array();
-		foreach ($this->messages as $message) {
-			$messages[] = $this->formatMessage($message);
-		}
-		@file_put_contents($this->logFile, implode('', $messages), FILE_APPEND | LOCK_EX);
 	}
 
 	/**
diff --git a/framework/logging/Logger.php b/framework/logging/Logger.php
index c139193..a8ffb5e 100644
--- a/framework/logging/Logger.php
+++ b/framework/logging/Logger.php
@@ -8,16 +8,13 @@
  */
 
 namespace yii\logging;
-
-use yii\base\Event;
-use yii\base\Exception;
+use yii\base\InvalidConfigException;
 
 /**
  * Logger records logged messages in memory.
  *
- * When [[flushInterval()]] is reached or when application terminates, it will
- * call [[flush()]] to send logged messages to different log targets, such as
- * file, email, Web.
+ * When the application ends or [[flushInterval]] is reached, Logger will call [[flush()]]
+ * to send logged messages to different log targets, such as file, email, Web.
  *
  * @author Qiang Xue <qiang.xue@gmail.com>
  * @since 2.0
@@ -25,15 +22,6 @@ use yii\base\Exception;
 class Logger extends \yii\base\Component
 {
 	/**
-	 * @event Event an event that is triggered when [[flush()]] is called.
-	 */
-	const EVENT_FLUSH = 'flush';
-	/**
-	 * @event Event an event that is triggered when [[flush()]] is called at the end of application.
-	 */
-	const EVENT_FINAL_FLUSH = 'finalFlush';
-
-	/**
 	 * Error message level. An error message is one that indicates the abnormal termination of the
 	 * application and may require developer's handling.
 	 */
@@ -82,7 +70,7 @@ class Logger extends \yii\base\Component
 	 *
 	 * ~~~
 	 * array(
-	 *   [0] => message (mixed)
+	 *   [0] => message (mixed, can be a string or some complex data, such as an exception object)
 	 *   [1] => level (integer)
 	 *   [2] => category (string)
 	 *   [3] => timestamp (float, obtained by microtime(true))
@@ -90,6 +78,10 @@ class Logger extends \yii\base\Component
 	 * ~~~
 	 */
 	public $messages = array();
+	/**
+	 * @var Router the log target router registered with this logger.
+	 */
+	public $router;
 
 	/**
 	 * Initializes the logger by registering [[flush()]] as a shutdown function.
@@ -138,7 +130,9 @@ class Logger extends \yii\base\Component
 	 */
 	public function flush($final = false)
 	{
-		$this->trigger($final ? self::EVENT_FINAL_FLUSH : self::EVENT_FLUSH);
+		if ($this->router) {
+			$this->router->dispatch($this->messages, $final);
+		}
 		$this->messages = array();
 	}
 
@@ -149,7 +143,7 @@ class Logger extends \yii\base\Component
 	 * of [[YiiBase]] class file.
 	 * @return float the total elapsed time in seconds for current request.
 	 */
-	public function getExecutionTime()
+	public function getElapsedTime()
 	{
 		return microtime(true) - YII_BEGIN_TIME;
 	}
@@ -218,7 +212,7 @@ class Logger extends \yii\base\Component
 				if (($last = array_pop($stack)) !== null && $last[0] === $token) {
 					$timings[] = array($token, $category, $timestamp - $last[3]);
 				} else {
-					throw new Exception("Unmatched profiling block: $token");
+					throw new InvalidConfigException("Unmatched profiling block: $token");
 				}
 			}
 		}
@@ -231,5 +225,4 @@ class Logger extends \yii\base\Component
 
 		return $timings;
 	}
-
 }
diff --git a/framework/logging/Router.php b/framework/logging/Router.php
index 75fbbc0..2e6a8dd 100644
--- a/framework/logging/Router.php
+++ b/framework/logging/Router.php
@@ -81,26 +81,21 @@ class Router extends Component
 				$this->targets[$name] = Yii::createObject($target);
 			}
 		}
-
-		Yii::getLogger()->on(Logger::EVENT_FLUSH, array($this, 'processMessages'));
-		Yii::getLogger()->on(Logger::EVENT_FINAL_FLUSH, array($this, 'processMessages'));
+		Yii::getLogger()->router = $this;
 	}
 
 	/**
-	 * Retrieves and processes log messages from the system logger.
-	 * This method mainly serves the event handler to the [[Logger::EVENT_FLUSH]] event
-	 * and the [[Logger::EVENT_FINAL_FLUSH]] event.
-	 * It will retrieve the available log messages from the [[Yii::getLogger()|system logger]]
-	 * and invoke the registered [[targets|log targets]] to do the actual processing.
-	 * @param \yii\base\Event $event event parameter
+	 * Dispatches log messages to [[targets]].
+	 * This method is called by [[Logger]] when its [[Logger::flush()]] method is called.
+	 * It will forward the messages to each log target registered in [[targets]].
+	 * @param array $messages the messages to be processed
+	 * @param boolean $final whether this is the final call during a request cycle
 	 */
-	public function processMessages($event)
+	public function dispatch($messages, $final = false)
 	{
-		$messages = Yii::getLogger()->messages;
-		$final = $event->name === Logger::EVENT_FINAL_FLUSH;
 		foreach ($this->targets as $target) {
 			if ($target->enabled) {
-				$target->processMessages($messages, $final);
+				$target->collect($messages, $final);
 			}
 		}
 	}
diff --git a/framework/logging/Target.php b/framework/logging/Target.php
index a4e7714..c9e175a 100644
--- a/framework/logging/Target.php
+++ b/framework/logging/Target.php
@@ -50,15 +50,6 @@ abstract class Target extends \yii\base\Component
 	 */
 	public $except = array();
 	/**
-	 * @var boolean whether to prefix each log message with the current session ID. Defaults to false.
-	 */
-	public $prefixSession = false;
-	/**
-	 * @var boolean whether to prefix each log message with the current user name and ID. Defaults to false.
-	 * @see \yii\web\User
-	 */
-	public $prefixUser = false;
-	/**
 	 * @var boolean whether to log a message containing the current user name and ID. Defaults to false.
 	 * @see \yii\web\User
 	 */
@@ -77,19 +68,18 @@ abstract class Target extends \yii\base\Component
 	public $exportInterval = 1000;
 	/**
 	 * @var array the messages that are retrieved from the logger so far by this log target.
-	 * @see autoExport
 	 */
-	public $messages = array();
+	private $_messages = array();
 
 	private $_levels = 0;
 
 	/**
 	 * Exports log messages to a specific destination.
-	 * Child classes must implement this method. Note that you may need
-	 * to clean up [[messages]] in this method to avoid re-exporting messages.
-	 * @param boolean $final whether this method is called at the end of the current application
+	 * Child classes must implement this method.
+	 * @param array $messages the messages to be exported. See [[Logger::messages]] for the structure
+	 * of each message.
 	 */
-	abstract public function exportMessages($final);
+	abstract public function export($messages);
 
 	/**
 	 * Processes the given log messages.
@@ -99,45 +89,16 @@ abstract class Target extends \yii\base\Component
 	 * of each message.
 	 * @param boolean $final whether this method is called at the end of the current application
 	 */
-	public function processMessages($messages, $final)
+	public function collect($messages, $final)
 	{
-		$messages = $this->filterMessages($messages);
-		$this->messages = array_merge($this->messages, $messages);
-
-		$count = count($this->messages);
+		$this->_messages = array($this->_messages, $this->filterMessages($messages));
+		$count = count($this->_messages);
 		if ($count > 0 && ($final || $this->exportInterval > 0 && $count >= $this->exportInterval)) {
-			$this->prepareExport($final);
-			$this->exportMessages($final);
-			$this->messages = array();
-		}
-	}
-
-	/**
-	 * Prepares the [[messages]] for exporting.
-	 * This method will modify each message by prepending extra information
-	 * if [[prefixSession]] and/or [[prefixUser]] are set true.
-	 * It will also add an additional message showing context information if
-	 * [[logUser]] and/or [[logVars]] are set.
-	 * @param boolean $final whether this method is called at the end of the current application
-	 */
-	protected function prepareExport($final)
-	{
-		$prefix = array();
-		if ($this->prefixSession && ($id = session_id()) !== '') {
-			$prefix[] = "[$id]";
-		}
-		if ($this->prefixUser && ($user = \Yii::$application->getComponent('user', false)) !== null) {
-			$prefix[] = '[' . $user->getName() . ']';
-			$prefix[] = '[' . $user->getId() . ']';
-		}
-		if ($prefix !== array()) {
-			$prefix = implode(' ', $prefix);
-			foreach ($this->messages as $i => $message) {
-				$this->messages[$i][0] = $prefix . ' ' . $this->messages[$i][0];
+			if (($context = $this->getContextMessage()) !== '') {
+				$this->_messages[] = array($context, Logger::LEVEL_INFO, 'application', YII_BEGIN_TIME);
 			}
-		}
-		if ($final && ($context = $this->getContextMessage()) !== '') {
-			$this->messages[] = array($context, Logger::LEVEL_INFO, 'application', YII_BEGIN_TIME);
+			$this->export($this->_messages);
+			$this->_messages = array();
 		}
 	}
 
@@ -164,7 +125,7 @@ abstract class Target extends \yii\base\Component
 
 	/**
 	 * @return integer the message levels that this target is interested in. This is a bitmap of
-	 * level values. Defaults to 0, meaning all available levels.
+	 * level values. Defaults to 0, meaning  all available levels.
 	 */
 	public function getLevels()
 	{
diff --git a/framework/util/FileHelper.php b/framework/util/FileHelper.php
index b0b0611..d340338 100644
--- a/framework/util/FileHelper.php
+++ b/framework/util/FileHelper.php
@@ -10,6 +10,7 @@
 namespace yii\util;
 
 use yii\base\Exception;
+use yii\base\InvalidConfigException;
 
 /**
  * Filesystem helper
@@ -37,7 +38,7 @@ class FileHelper
 	 * If the given path does not refer to an existing directory, an exception will be thrown.
 	 * @param string $path the given path. This can also be a path alias.
 	 * @return string the normalized path
-	 * @throws Exception if the path does not refer to an existing directory.
+	 * @throws InvalidConfigException if the path does not refer to an existing directory.
 	 */
 	public static function ensureDirectory($path)
 	{
@@ -45,7 +46,7 @@ class FileHelper
 		if ($p !== false && ($p = realpath($p)) !== false && is_dir($p)) {
 			return $p;
 		} else {
-			throw new Exception('Directory does not exist: ' . $path);
+			throw new InvalidConfigException('Directory does not exist: ' . $path);
 		}
 	}