From c225242290d28c2a1666ac158981c9a2f45b50cc Mon Sep 17 00:00:00 2001
From: Qiang Xue <qiang.xue@gmail.com>
Date: Mon, 28 May 2012 13:45:50 -0400
Subject: [PATCH] working on caching.

---
 framework/base/ErrorHandler.php                  |   2 +-
 framework/base/InlineActionFilter.php            |  61 -------
 framework/base/SecurityManager.php               |   8 +-
 framework/caching/ApcCache.php                   |   9 +-
 framework/caching/Cache.php                      | 198 +++++++++--------------
 framework/caching/CacheDependency.php            | 113 +++++++++++++
 framework/caching/ChainedDependency.php          |   9 +-
 framework/caching/DbCache.php                    |  14 +-
 framework/caching/DbDependency.php               |  12 +-
 framework/caching/Dependency.php                 |   9 +-
 framework/caching/DirectoryDependency.php        |  10 +-
 framework/caching/DummyCache.php                 |  13 +-
 framework/caching/EAcceleratorCache.php          |  11 +-
 framework/caching/ExpressionDependency.php       |   9 +-
 framework/caching/FileCache.php                  |  10 +-
 framework/caching/FileDependency.php             |  10 +-
 framework/caching/MemCache.php                   |   9 +-
 framework/caching/WinCache.php                   |  11 +-
 framework/caching/XCache.php                     |  10 +-
 framework/caching/ZendDataCache.php              |  10 +-
 framework/console/commands/MigrateController.php |   2 +-
 framework/console/commands/ShellController.php   |   2 +-
 framework/web/AssetManager.php                   |   4 +-
 framework/web/Request.php                        |  14 +-
 framework/web/Sort.php                           |   2 +-
 framework/web/Theme.php                          |   2 +-
 framework/web/ThemeManager.php                   |   4 +-
 framework/web/UrlManager.php                     |   8 +-
 28 files changed, 289 insertions(+), 287 deletions(-)
 delete mode 100644 framework/base/InlineActionFilter.php
 create mode 100644 framework/caching/CacheDependency.php

diff --git a/framework/base/ErrorHandler.php b/framework/base/ErrorHandler.php
index fad88ab..dd9d77f 100644
--- a/framework/base/ErrorHandler.php
+++ b/framework/base/ErrorHandler.php
@@ -34,7 +34,7 @@ class ErrorHandler extends ApplicationComponent
 	public $discardExistingOutput = true;
 	/**
 	 * @var string the route (eg 'site/error') to the controller action that will be used to display external errors.
-	 * Inside the action, it can retrieve the error information by Yii::app()->errorHandler->error.
+	 * Inside the action, it can retrieve the error information by \Yii::$application->errorHandler->error.
 	 * This property defaults to null, meaning ErrorHandler will handle the error display.
 	 */
 	public $errorAction;
diff --git a/framework/base/InlineActionFilter.php b/framework/base/InlineActionFilter.php
deleted file mode 100644
index 9d7b18a..0000000
--- a/framework/base/InlineActionFilter.php
+++ /dev/null
@@ -1,61 +0,0 @@
-<?php
-/**
- * CInlineFilter class file.
- *
- * @author Qiang Xue <qiang.xue@gmail.com>
- * @link http://www.yiiframework.com/
- * @copyright Copyright &copy; 2008-2011 Yii Software LLC
- * @license http://www.yiiframework.com/license/
- */
-
-/**
- * CInlineFilter represents a filter defined as a controller method.
- *
- * CInlineFilter executes the 'filterXYZ($action)' method defined
- * in the controller, where the name 'XYZ' can be retrieved from the {@link name} property.
- *
- * @author Qiang Xue <qiang.xue@gmail.com>
- * @version $Id$
- * @package system.web.filters
- * @since 1.0
- */
-class CInlineFilter extends CFilter
-{
-	/**
-	 * @var string name of the filter. It stands for 'XYZ' in the filter method name 'filterXYZ'.
-	 */
-	public $name;
-
-	/**
-	 * Creates an inline filter instance.
-	 * The creation is based on a string describing the inline method name
-	 * and action names that the filter shall or shall not apply to.
-	 * @param CController $controller the controller who hosts the filter methods
-	 * @param string $filterName the filter name
-	 * @return CInlineFilter the created instance
-	 * @throws CException if the filter method does not exist
-	 */
-	public static function create($controller,$filterName)
-	{
-		if(method_exists($controller,'filter'.$filterName))
-		{
-			$filter=new CInlineFilter;
-			$filter->name=$filterName;
-			return $filter;
-		}
-		else
-			throw new CException(Yii::t('yii','Filter "{filter}" is invalid. Controller "{class}" does not have the filter method "filter{filter}".',
-				array('{filter}'=>$filterName, '{class}'=>get_class($controller))));
-	}
-
-	/**
-	 * Performs the filtering.
-	 * This method calls the filter method defined in the controller class.
-	 * @param CFilterChain $filterChain the filter chain that the filter is on.
-	 */
-	public function filter($filterChain)
-	{
-		$method='filter'.$this->name;
-		$filterChain->controller->$method($filterChain);
-	}
-}
diff --git a/framework/base/SecurityManager.php b/framework/base/SecurityManager.php
index 53c6a9c..6520daf 100644
--- a/framework/base/SecurityManager.php
+++ b/framework/base/SecurityManager.php
@@ -99,13 +99,13 @@ class SecurityManager extends ApplicationComponent
 			return $this->_validationKey;
 		}
 		else {
-			if (($key = Yii::app()->getGlobalState(self::STATE_VALIDATION_KEY)) !== null) {
+			if (($key = \Yii::$application->getGlobalState(self::STATE_VALIDATION_KEY)) !== null) {
 				$this->setValidationKey($key);
 			}
 			else {
 				$key = $this->generateRandomKey();
 				$this->setValidationKey($key);
-				Yii::app()->setGlobalState(self::STATE_VALIDATION_KEY, $key);
+				\Yii::$application->setGlobalState(self::STATE_VALIDATION_KEY, $key);
 			}
 			return $this->_validationKey;
 		}
@@ -135,13 +135,13 @@ class SecurityManager extends ApplicationComponent
 			return $this->_encryptionKey;
 		}
 		else {
-			if (($key = Yii::app()->getGlobalState(self::STATE_ENCRYPTION_KEY)) !== null) {
+			if (($key = \Yii::$application->getGlobalState(self::STATE_ENCRYPTION_KEY)) !== null) {
 				$this->setEncryptionKey($key);
 			}
 			else {
 				$key = $this->generateRandomKey();
 				$this->setEncryptionKey($key);
-				Yii::app()->setGlobalState(self::STATE_ENCRYPTION_KEY, $key);
+				\Yii::$application->setGlobalState(self::STATE_ENCRYPTION_KEY, $key);
 			}
 			return $this->_encryptionKey;
 		}
diff --git a/framework/caching/ApcCache.php b/framework/caching/ApcCache.php
index 430269f..25d2f85 100644
--- a/framework/caching/ApcCache.php
+++ b/framework/caching/ApcCache.php
@@ -2,12 +2,13 @@
 /**
  * CApcCache class file
  *
- * @author Qiang Xue <qiang.xue@gmail.com>
  * @link http://www.yiiframework.com/
- * @copyright Copyright &copy; 2008-2011 Yii Software LLC
+ * @copyright Copyright &copy; 2008-2012 Yii Software LLC
  * @license http://www.yiiframework.com/license/
  */
 
+namespace yii\caching;
+
 /**
  * CApcCache provides APC caching in terms of an application component.
  *
@@ -17,9 +18,7 @@
  * See {@link CCache} manual for common cache operations that are supported by CApcCache.
  *
  * @author Qiang Xue <qiang.xue@gmail.com>
- * @version $Id$
- * @package system.caching
- * @since 1.0
+ * @since 2.0
  */
 class CApcCache extends CCache
 {
diff --git a/framework/caching/Cache.php b/framework/caching/Cache.php
index 1470a29..239ab18 100644
--- a/framework/caching/Cache.php
+++ b/framework/caching/Cache.php
@@ -1,15 +1,19 @@
 <?php
 /**
- * CCache class file.
+ * Cache class file.
  *
- * @author Qiang Xue <qiang.xue@gmail.com>
  * @link http://www.yiiframework.com/
- * @copyright Copyright &copy; 2008-2011 Yii Software LLC
+ * @copyright Copyright &copy; 2008-2012 Yii Software LLC
  * @license http://www.yiiframework.com/license/
  */
 
+namespace yii\caching;
+
+use yii\base\ApplicationComponent;
+use yii\base\Exception;
+
 /**
- * CCache is the base class for cache classes with different cache storage implementation.
+ * Cache is the base class for cache classes with different cache storage implementation.
  *
  * A data item can be stored in cache by calling {@link set} and be retrieved back
  * later by {@link get}. In both operations, a key identifying the data item is required.
@@ -20,7 +24,7 @@
  * Note, by definition, cache does not ensure the existence of a value
  * even if it does not expire. Cache is not meant to be a persistent storage.
  *
- * CCache implements the interface {@link ICache} with the following methods:
+ * Cache implements the interface {@link ICache} with the following methods:
  * <ul>
  * <li>{@link get} : retrieve the value with a key (if any) from cache</li>
  * <li>{@link set} : store the value with a key into cache</li>
@@ -40,12 +44,10 @@
  * <li>{@link unserializeValue} (optional)</li>
  * </ul>
  *
- * CCache also implements ArrayAccess so that it can be used like an array.
+ * Cache also implements ArrayAccess so that it can be used like an array.
  *
  * @author Qiang Xue <qiang.xue@gmail.com>
- * @version $Id$
- * @package system.caching
- * @since 1.0
+ * @since 2.0
  */
 abstract class Cache extends ApplicationComponent implements \ArrayAccess
 {
@@ -55,36 +57,25 @@ abstract class Cache extends ApplicationComponent implements \ArrayAccess
 	 * pool of cached data, the same prefix should be set for each of the applications explicitly.
 	 */
 	public $keyPrefix;
-
 	/**
-	 * @var boolean whether to md5-hash the cache key for normalization purposes. Defaults to true. Setting this property to false makes sure the cache
+	 * @var boolean whether to hash the cache key for normalization purpose. Defaults to true.
+	 * Setting this property to false makes sure the cache
 	 * key will not be tampered when calling the relevant methods {@link get()}, {@link set()}, {@link add()} and {@link delete()}. This is useful if a Yii
 	 * application as well as an external application need to access the same cache pool (also see description of {@link keyPrefix} regarding this use case).
 	 * However, without normalization you should make sure the affected cache backend does support the structure (charset, length, etc.) of all the provided
 	 * cache keys, otherwise there might be unexpected behavior.
-	 * @since 1.1.11
 	 **/
 	public $hashKey = true;
-
-	/**
-	 * @var boolean whether to automatically serialize/unserialize the cache values. Defaults to true. Setting this property to false makes sure the cache
-	 * value will not be tampered when calling the methods {@link set()} and {@link add()}. This is useful in case you want to store data which simply
-	 * does not require serialization (e.g. integers, strings or raw binary data). Thus there might be a small increase in performance and a smaller overall
-	 * cache size. Take in mind that you will be unable to store PHP structures like arrays or objects, you would have to serialize and unserialize them manually.
-	 * Another negative side effect is that providing a dependency via {@link set()} or {@link add()} will have no effect since dependencies rely on serialization.
-	 * Since all the relevant core application components rely on dependency support, you should be very careful disabling this feature. Usually you want to
-	 * configure a dedicated cache component for the sole purpose of storing raw unserialized data, the main cache component should always support serialization.
-	 * @since 1.1.11
-	 **/
-	public $autoSerialize = true;
-
 	/**
-	 * @var boolean wether to make use of the {@link http://pecl.php.net/package/igbinary igbinary} serializer for cache entry serialization. Defaults to false.
-	 * <strong>NOTE:</strong> If this is set to true while the igbinary extension has not been loaded, cache serialization will silently fall back to PHP's default
-	 * serializer. Since the two serialization formats are incompatible, caches should be purged before switching this on to prevent errors.
-	 * @since 1.1.11
+	 * @var array|boolean the functions used to serialize and unserialize cached data. Defaults to null, meaning
+	 * using the default PHP `serialize()` and `unserialize()` functions. If you want to use some more efficient
+	 * serializer (e.g. [igbinary](http://pecl.php.net/package/igbinary)), you may configure this property with
+	 * a two-element array. The first element specifies the serialization function, and the second the deserialization
+	 * function. If this property is set false, data will be directly sent to and retrieved from the underlying
+	 * cache component without any serialization or deserialization. You should not turn off serialization if
+	 * you are using [[CacheDependency|cache dependency]], because it relies on data serialization.
 	 */
-	public $useIgbinarySerializer = false;
+	public $serializer;
 
 	/**
 	 * Initializes the application component.
@@ -94,16 +85,15 @@ abstract class Cache extends ApplicationComponent implements \ArrayAccess
 	{
 		parent::init();
 		if ($this->keyPrefix === null) {
-			$this->keyPrefix = Yii::app()->getId();
+			$this->keyPrefix = \Yii::$application->id;
 		}
-		$this->useIgbinarySerializer = $this->useIgbinarySerializer && extension_loaded('igbinary');
 	}
 
 	/**
 	 * @param string $key a key identifying a value to be cached
-	 * @return sring a key generated from the provided key which ensures the uniqueness across applications
+	 * @return string a key generated from the provided key which ensures the uniqueness across applications
 	 */
-	protected function generateUniqueKey($key)
+	protected function generateCacheKey($key)
 	{
 		return $this->hashKey ? md5($this->keyPrefix . $key) : $this->keyPrefix . $key;
 	}
@@ -111,18 +101,24 @@ abstract class Cache extends ApplicationComponent implements \ArrayAccess
 	/**
 	 * Retrieves a value from cache with a specified key.
 	 * @param string $id a key identifying the cached value
-	 * @return mixed the value stored in cache, false if the value is not in the cache, expired or the dependency has changed.
+	 * @return mixed the value stored in cache, false if the value is not in the cache, expired,
+	 * or the dependency associated with the cached data has changed.
 	 */
 	public function get($id)
 	{
-		if (($value = $this->getValue($this->generateUniqueKey($id))) !== false) {
-			$data = $this->autoSerialize ? $this->unserializeValue($value) : $value;
-			if (!$this->autoSerialize || (is_array($data) && (!($data[1] instanceof ICacheDependency) || !$data[1]->getHasChanged()))) {
-				Yii::trace('Serving "' . $id . '" from cache', 'system.caching.' . get_class($this));
-				return $this->autoSerialize ? $data[0] : $data;
-			}
+		$value = $this->getValue($this->generateCacheKey($id));
+		if ($value === false || $this->serializer === false) {
+			return $value;
+		} elseif ($this->serializer === null) {
+			$value = unserialize($value);
+		} else {
+			$value = call_user_func($this->serializer[1], $value);
+		}
+		if (is_array($value) && ($value[1] instanceof CacheDependency) || !$value[1]->getHasChanged()) {
+			return $value[0];
+		} else {
+			return false;
 		}
-		return false;
 	}
 
 	/**
@@ -135,23 +131,27 @@ abstract class Cache extends ApplicationComponent implements \ArrayAccess
 	 * is returned in terms of (key,value) pairs.
 	 * If a value is not cached or expired, the corresponding array value will be false.
 	 */
-	public function mget($ids)
+	public function mget(array $ids)
 	{
-		$uniqueIDs = array();
-		$results = array();
+		$uids = array();
 		foreach ($ids as $id) {
-			$uniqueIDs[$id] = $this->generateUniqueKey($id);
-			$results[$id] = false;
+			$uids[$id] = $this->generateCacheKey($id);
 		}
-		$values = $this->getValues($uniqueIDs);
-		foreach ($uniqueIDs as $id => $uniqueID) {
-			if (!isset($values[$uniqueID])) {
-				continue;
+		$values = $this->getValues($uids);
+		$results = array();
+		if ($this->serializer === false) {
+			foreach ($uids as $id => $uid) {
+				$results[$id] = isset($values[$uid]) ? $values[$uid] : false;
 			}
-			$data = $this->autoSerialize ? $this->unserializeValue($values[$uniqueID]) : $values[$uniqueID];
-			if (!$this->autoSerialize || (is_array($data) && (!($data[1] instanceof ICacheDependency) || !$data[1]->getHasChanged()))) {
-				Yii::trace('Serving "' . $id . '" from cache', 'system.caching.' . get_class($this));
-				$results[$id] = $this->autoSerialize ? $data[0] : $data;
+		} else {
+			foreach ($uids as $id => $uid) {
+				$results[$id] = false;
+				if (isset($values[$uid])) {
+					$value = $this->serializer === null ? unserialize($values[$uid]) : call_user_func($this->serializer[1], $values[$uid]);
+					if (is_array($value) && (!($value[1] instanceof CacheDependency) || !$value[1]->getHasChanged())) {
+						$results[$id] = $value[0];
+					}
+				}
 			}
 		}
 		return $results;
@@ -165,17 +165,20 @@ abstract class Cache extends ApplicationComponent implements \ArrayAccess
 	 * @param string $id the key identifying the value to be cached
 	 * @param mixed $value the value to be cached
 	 * @param integer $expire the number of seconds in which the cached value will expire. 0 means never expire.
-	 * @param ICacheDependency $dependency dependency of the cached item. If the dependency changes, the item is labeled invalid.
+	 * @param CacheDependency $dependency dependency of the cached item. If the dependency changes, the item is labeled invalid.
 	 * @return boolean true if the value is successfully stored into cache, false otherwise
 	 */
 	public function set($id, $value, $expire = 0, $dependency = null)
 	{
-		Yii::trace('Saving "' . $id . '" to cache', 'system.caching.' . get_class($this));
-		if ($dependency !== null && $this->autoSerialize) {
+		if ($dependency !== null && $this->serializer !== false) {
 			$dependency->evaluateDependency();
 		}
-		$data = $this->autoSerialize ? $this->serializeValue(array($value, $dependency)) : $value;
-		return $this->setValue($this->generateUniqueKey($id), $data, $expire);
+		if ($this->serializer === null) {
+			$value = array(serialize($value), $dependency);
+		} elseif ($this->serializer !== false) {
+			$value = array(call_user_func($this->serializer[0], $value), $dependency);
+		}
+		return $this->setValue($this->generateCacheKey($id), $value, $expire);
 	}
 
 	/**
@@ -184,17 +187,20 @@ abstract class Cache extends ApplicationComponent implements \ArrayAccess
 	 * @param string $id the key identifying the value to be cached
 	 * @param mixed $value the value to be cached
 	 * @param integer $expire the number of seconds in which the cached value will expire. 0 means never expire.
-	 * @param ICacheDependency $dependency dependency of the cached item. If the dependency changes, the item is labeled invalid.
+	 * @param CacheDependency $dependency dependency of the cached item. If the dependency changes, the item is labeled invalid.
 	 * @return boolean true if the value is successfully stored into cache, false otherwise
 	 */
 	public function add($id, $value, $expire = 0, $dependency = null)
 	{
-		Yii::trace('Adding "' . $id . '" to cache', 'system.caching.' . get_class($this));
-		if ($dependency !== null && $this->autoSerialize) {
+		if ($dependency !== null && $this->serializer !== false) {
 			$dependency->evaluateDependency();
 		}
-		$data = $this->autoSerialize ? $this->serializeValue(array($value, $dependency)) : $value;
-		return $this->addValue($this->generateUniqueKey($id), $data, $expire);
+		if ($this->serializer === null) {
+			$value = array(serialize($value), $dependency);
+		} elseif ($this->serializer !== false) {
+			$value = array(call_user_func($this->serializer[0], $value), $dependency);
+		}
+		return $this->addValue($this->generateCacheKey($id), $value, $expire);
 	}
 
 	/**
@@ -204,8 +210,7 @@ abstract class Cache extends ApplicationComponent implements \ArrayAccess
 	 */
 	public function delete($id)
 	{
-		Yii::trace('Deleting "' . $id . '" from cache', 'system.caching.' . get_class($this));
-		return $this->deleteValue($this->generateUniqueKey($id));
+		return $this->deleteValue($this->generateCacheKey($id));
 	}
 
 	/**
@@ -215,7 +220,6 @@ abstract class Cache extends ApplicationComponent implements \ArrayAccess
 	 */
 	public function flush()
 	{
-		Yii::trace('Flushing cache', 'system.caching.' . get_class($this));
 		return $this->flushValues();
 	}
 
@@ -227,12 +231,10 @@ abstract class Cache extends ApplicationComponent implements \ArrayAccess
 	 * is needed.
 	 * @param string $key a unique key identifying the cached value
 	 * @return string the value stored in cache, false if the value is not in the cache or expired.
-	 * @throws CException if this method is not overridden by child classes
 	 */
 	protected function getValue($key)
 	{
-		throw new CException(Yii::t('yii', '{className} does not support get() functionality.',
-			array('{className}' => get_class($this))));
+		return false;
 	}
 
 	/**
@@ -264,12 +266,10 @@ abstract class Cache extends ApplicationComponent implements \ArrayAccess
 	 * @param string $value the value to be cached
 	 * @param integer $expire the number of seconds in which the cached value will expire. 0 means never expire.
 	 * @return boolean true if the value is successfully stored into cache, false otherwise
-	 * @throws CException if this method is not overridden by child classes
 	 */
 	protected function setValue($key, $value, $expire)
 	{
-		throw new CException(Yii::t('yii', '{className} does not support set() functionality.',
-			array('{className}' => get_class($this))));
+		return true;
 	}
 
 	/**
@@ -283,12 +283,10 @@ abstract class Cache extends ApplicationComponent implements \ArrayAccess
 	 * @param string $value the value to be cached
 	 * @param integer $expire the number of seconds in which the cached value will expire. 0 means never expire.
 	 * @return boolean true if the value is successfully stored into cache, false otherwise
-	 * @throws CException if this method is not overridden by child classes
 	 */
 	protected function addValue($key, $value, $expire)
 	{
-		throw new CException(Yii::t('yii', '{className} does not support add() functionality.',
-			array('{className}' => get_class($this))));
+		return true;
 	}
 
 	/**
@@ -296,61 +294,20 @@ abstract class Cache extends ApplicationComponent implements \ArrayAccess
 	 * This method should be implemented by child classes to delete the data from actual cache storage.
 	 * @param string $key the key of the value to be deleted
 	 * @return boolean if no error happens during deletion
-	 * @throws CException if this method is not overridden by child classes
 	 */
 	protected function deleteValue($key)
 	{
-		throw new CException(Yii::t('yii', '{className} does not support delete() functionality.',
-			array('{className}' => get_class($this))));
+		return true;
 	}
 
 	/**
 	 * Deletes all values from cache.
 	 * Child classes may implement this method to realize the flush operation.
 	 * @return boolean whether the flush operation was successful.
-	 * @throws CException if this method is not overridden by child classes
-	 * @since 1.1.5
 	 */
 	protected function flushValues()
 	{
-		throw new CException(Yii::t('yii', '{className} does not support flushValues() functionality.',
-			array('{className}' => get_class($this))));
-	}
-
-	/**
-	 * Serializes the value before it will be stored in the actual cache backend.
-	 * This method will be called if {@link autoSerialize} is set to true. Child classes may override this method to change
-	 * the way the value is being serialized. The default implementation simply makes use of the PHP serialize() function
-	 * unless {@link useIgbinarySerializer} is set to true and the igbinary extension is installed.
-	 * Make sure to override {@link unserializeValue()} as well if you want to change the serialization process.
-	 * @param mixed $value the unserialized representation of the value
-	 * @return string the serialized representation of the value
-	 * @since 1.1.11
-	 **/
-	protected function serializeValue($value)
-	{
-		if ($this->useIgbinarySerializer) {
-			return igbinary_serialize($value);
-		}
-		return serialize($value);
-	}
-
-	/**
-	 * Unserializes the value after it was retrieved from the actual cache backend.
-	 * This method will be called if {@link autoSerialize} is set to true. Child classes may override this method to change
-	 * the way the value is being unserialized.  The default implementation simply makes use of the PHP unserialize() function
-	 * unless {@link useIgbinarySerializer} is set to true and the igbinary extension is installed.
-	 * Make sure to override {@link serializeValue()} as well if you want to change the serialization process.
-	 * @param string $value the serialized representation of the value
-	 * @return mixed the unserialized representation of the value
-	 * @since 1.1.11
-	 **/
-	protected function unserializeValue($value)
-	{
-		if ($this->useIgbinarySerializer) {
-			return igbinary_unserialize($value);
-		}
-		return unserialize($value);
+		return true;
 	}
 
 	/**
@@ -392,7 +349,6 @@ abstract class Cache extends ApplicationComponent implements \ArrayAccess
 	 * Deletes the value with the specified key from cache
 	 * This method is required by the interface ArrayAccess.
 	 * @param string $id the key of the value to be deleted
-	 * @return boolean if no error happens during deletion
 	 */
 	public function offsetUnset($id)
 	{
diff --git a/framework/caching/CacheDependency.php b/framework/caching/CacheDependency.php
new file mode 100644
index 0000000..208400d
--- /dev/null
+++ b/framework/caching/CacheDependency.php
@@ -0,0 +1,113 @@
+<?php
+/**
+ * CacheDependency class file.
+ *
+ * @link http://www.yiiframework.com/
+ * @copyright Copyright &copy; 2008-2012 Yii Software LLC
+ * @license http://www.yiiframework.com/license/
+ */
+
+namespace yii\caching;
+
+/**
+ * CacheDependency is the base class for cache dependency classes.
+ *
+ * CacheDependency implements the {@link ICacheDependency} interface.
+ * Child classes should override its {@link generateDependentData} for
+ * actual dependency checking.
+ *
+ * @property boolean $hasChanged Whether the dependency has changed.
+ * @property mixed $dependentData The data used to determine if dependency has been changed.
+ * This data is available after {@link evaluateDependency} is called.
+ *
+ * @author Qiang Xue <qiang.xue@gmail.com>
+ * @since 2.0
+ */
+class CacheDependency extends \yii\base\Object
+{
+	/**
+	 * @var boolean Whether this dependency is reusable or not.
+	 * If set to true, dependent data for this cache dependency will only be generated once per request.
+	 * You can then use the same cache dependency for multiple separate cache calls on the same page
+	 * without the overhead of re-evaluating the dependency each time.
+	 * Defaults to false;
+	 * @since 1.1.11
+	 */
+	public $reuseDependentData = false;
+
+	/**
+	 * @var array cached data for reusable dependencies.
+	 * @since 1.1.11
+	 */
+	private static $_reusableData = array();
+
+	private $_hash;
+	private $_data;
+
+	/**
+	 * Evaluates the dependency by generating and saving the data related with dependency.
+	 * This method is invoked by cache before writing data into it.
+	 */
+	public function evaluateDependency()
+	{
+		if ($this->reuseDependentData) {
+			$hash = $this->getHash();
+			if (!isset(self::$_reusableData[$hash]['dependentData'])) {
+				self::$_reusableData[$hash]['dependentData'] = $this->generateDependentData();
+			}
+			$this->_data = self::$_reusableData[$hash]['dependentData'];
+		} else {
+			$this->_data = $this->generateDependentData();
+		}
+	}
+
+	/**
+	 * @return boolean whether the dependency has changed.
+	 */
+	public function getHasChanged()
+	{
+		if ($this->reuseDependentData) {
+			$hash = $this->getHash();
+			if (!isset(self::$_reusableData[$hash]['hasChanged'])) {
+				if (!isset(self::$_reusableData[$hash]['dependentData'])) {
+					self::$_reusableData[$hash]['dependentData'] = $this->generateDependentData();
+				}
+				self::$_reusableData[$hash]['hasChanged'] = self::$_reusableData[$hash]['dependentData'] != $this->_data;
+			}
+			return self::$_reusableData[$hash]['hasChanged'];
+		} else {
+			return $this->generateDependentData() != $this->_data;
+		}
+	}
+
+	/**
+	 * @return mixed the data used to determine if dependency has been changed.
+	 * This data is available after {@link evaluateDependency} is called.
+	 */
+	public function getDependentData()
+	{
+		return $this->_data;
+	}
+
+	/**
+	 * Generates the data needed to determine if dependency has been changed.
+	 * Derived classes should override this method to generate actual dependent data.
+	 * @return mixed the data needed to determine if dependency has been changed.
+	 */
+	protected function generateDependentData()
+	{
+		return null;
+	}
+
+	/**
+	 * Generates a unique hash that identifies this cache dependency.
+	 * @return string the hash for this cache dependency
+	 */
+	private function getHash()
+	{
+		if ($this->_hash === null) {
+			$this->_hash = sha1(serialize($this));
+		}
+		return $this->_hash;
+	}
+}
\ No newline at end of file
diff --git a/framework/caching/ChainedDependency.php b/framework/caching/ChainedDependency.php
index 4719542..28c0da6 100644
--- a/framework/caching/ChainedDependency.php
+++ b/framework/caching/ChainedDependency.php
@@ -2,12 +2,13 @@
 /**
  * CChainedCacheDependency class file.
  *
- * @author Qiang Xue <qiang.xue@gmail.com>
  * @link http://www.yiiframework.com/
- * @copyright Copyright &copy; 2008-2011 Yii Software LLC
+ * @copyright Copyright &copy; 2008-2012 Yii Software LLC
  * @license http://www.yiiframework.com/license/
  */
 
+namespace yii\caching;
+
 /**
  * CChainedCacheDependency represents a list of cache dependencies.
  *
@@ -22,9 +23,7 @@
  * @property boolean $hasChanged Whether the dependency is changed or not.
  *
  * @author Qiang Xue <qiang.xue@gmail.com>
- * @version $Id$
- * @package system.caching.dependencies
- * @since 1.0
+ * @since 2.0
  */
 class CChainedCacheDependency extends CComponent implements ICacheDependency
 {
diff --git a/framework/caching/DbCache.php b/framework/caching/DbCache.php
index ea886ee..59bcbc1 100644
--- a/framework/caching/DbCache.php
+++ b/framework/caching/DbCache.php
@@ -2,12 +2,14 @@
 /**
  * CDbCache class file
  *
- * @author Qiang Xue <qiang.xue@gmail.com>
  * @link http://www.yiiframework.com/
- * @copyright Copyright &copy; 2008-2011 Yii Software LLC
+ * @copyright Copyright &copy; 2008-2012 Yii Software LLC
  * @license http://www.yiiframework.com/license/
  */
 
+namespace yii\caching;
+
+
 /**
  * CDbCache implements a cache application component by storing cached data in a database.
  *
@@ -27,9 +29,7 @@
  * @property CDbConnection $dbConnection The DB connection instance.
  *
  * @author Qiang Xue <qiang.xue@gmail.com>
- * @version $Id$
- * @package system.caching
- * @since 1.0
+ * @since 2.0
  */
 class CDbCache extends CCache
 {
@@ -150,7 +150,7 @@ EOD;
 			return $this->_db;
 		else if(($id=$this->connectionID)!==null)
 		{
-			if(($this->_db=Yii::app()->getComponent($id)) instanceof CDbConnection)
+			if(($this->_db=\Yii::$application->getComponent($id)) instanceof CDbConnection)
 				return $this->_db;
 			else
 				throw new CException(Yii::t('yii','CDbCache.connectionID "{id}" is invalid. Please make sure it refers to the ID of a CDbConnection application component.',
@@ -158,7 +158,7 @@ EOD;
 		}
 		else
 		{
-			$dbFile=Yii::app()->getRuntimePath().DIRECTORY_SEPARATOR.'cache-'.Yii::getVersion().'.db';
+			$dbFile=\Yii::$application->getRuntimePath().DIRECTORY_SEPARATOR.'cache-'.Yii::getVersion().'.db';
 			return $this->_db=new CDbConnection('sqlite:'.$dbFile);
 		}
 	}
diff --git a/framework/caching/DbDependency.php b/framework/caching/DbDependency.php
index 6c92ee9..6a38a6c 100644
--- a/framework/caching/DbDependency.php
+++ b/framework/caching/DbDependency.php
@@ -2,12 +2,14 @@
 /**
  * CDbCacheDependency class file.
  *
- * @author Qiang Xue <qiang.xue@gmail.com>
  * @link http://www.yiiframework.com/
- * @copyright Copyright &copy; 2008-2011 Yii Software LLC
+ * @copyright Copyright &copy; 2008-2012 Yii Software LLC
  * @license http://www.yiiframework.com/license/
  */
 
+namespace yii\caching;
+
+
 /**
  * CDbCacheDependency represents a dependency based on the query result of a SQL statement.
  *
@@ -17,9 +19,7 @@
  * component. It is this DB connection that is used to perform the query.
  *
  * @author Qiang Xue <qiang.xue@gmail.com>
- * @version $Id$
- * @package system.caching.dependencies
- * @since 1.0
+ * @since 2.0
  */
 class CDbCacheDependency extends CCacheDependency
 {
@@ -102,7 +102,7 @@ class CDbCacheDependency extends CCacheDependency
 			return $this->_db;
 		else
 		{
-			if(($this->_db=Yii::app()->getComponent($this->connectionID)) instanceof CDbConnection)
+			if(($this->_db=\Yii::$application->getComponent($this->connectionID)) instanceof CDbConnection)
 				return $this->_db;
 			else
 				throw new CException(Yii::t('yii','CDbCacheDependency.connectionID "{id}" is invalid. Please make sure it refers to the ID of a CDbConnection application component.',
diff --git a/framework/caching/Dependency.php b/framework/caching/Dependency.php
index a131926..29b95d5 100644
--- a/framework/caching/Dependency.php
+++ b/framework/caching/Dependency.php
@@ -2,12 +2,13 @@
 /**
  * CCacheDependency class file.
  *
- * @author Qiang Xue <qiang.xue@gmail.com>
  * @link http://www.yiiframework.com/
- * @copyright Copyright &copy; 2008-2011 Yii Software LLC
+ * @copyright Copyright &copy; 2008-2012 Yii Software LLC
  * @license http://www.yiiframework.com/license/
  */
 
+namespace yii\caching;
+
 /**
  * CCacheDependency is the base class for cache dependency classes.
  *
@@ -20,9 +21,7 @@
  * This data is available after {@link evaluateDependency} is called.
  *
  * @author Qiang Xue <qiang.xue@gmail.com>
- * @version $Id$
- * @package system.caching.dependencies
- * @since 1.0
+ * @since 2.0
  */
 class CCacheDependency extends CComponent implements ICacheDependency
 {
diff --git a/framework/caching/DirectoryDependency.php b/framework/caching/DirectoryDependency.php
index 3aaa6b9..7244713 100644
--- a/framework/caching/DirectoryDependency.php
+++ b/framework/caching/DirectoryDependency.php
@@ -2,12 +2,14 @@
 /**
  * CDirectoryCacheDependency class file.
  *
- * @author Qiang Xue <qiang.xue@gmail.com>
  * @link http://www.yiiframework.com/
- * @copyright Copyright &copy; 2008-2011 Yii Software LLC
+ * @copyright Copyright &copy; 2008-2012 Yii Software LLC
  * @license http://www.yiiframework.com/license/
  */
 
+namespace yii\caching;
+
+
 /**
  * CDirectoryCacheDependency represents a dependency based on change of a directory.
  *
@@ -25,9 +27,7 @@
  * accessing modification time of multiple files under the directory.
  *
  * @author Qiang Xue <qiang.xue@gmail.com>
- * @version $Id$
- * @package system.caching.dependencies
- * @since 1.0
+ * @since 2.0
  */
 class CDirectoryCacheDependency extends CCacheDependency
 {
diff --git a/framework/caching/DummyCache.php b/framework/caching/DummyCache.php
index f78bcf3..83a6b5f 100644
--- a/framework/caching/DummyCache.php
+++ b/framework/caching/DummyCache.php
@@ -2,24 +2,23 @@
 /**
  * CDummyCache class file.
  *
- * @author Qiang Xue <qiang.xue@gmail.com>
  * @link http://www.yiiframework.com/
- * @copyright Copyright &copy; 2008-2011 Yii Software LLC
+ * @copyright Copyright &copy; 2008-2012 Yii Software LLC
  * @license http://www.yiiframework.com/license/
  */
 
+namespace yii\caching;
+
 /**
  * CDummyCache is a placeholder cache component.
  *
  * CDummyCache does not cache anything. It is provided so that one can always configure
- * a 'cache' application component and he does not need to check if Yii::app()->cache is null or not.
+ * a 'cache' application component and he does not need to check if \Yii::$application->cache is null or not.
  * By replacing CDummyCache with some other cache component, one can quickly switch from
  * non-caching mode to caching mode.
  *
  * @author Qiang Xue <qiang.xue@gmail.com>
- * @version $Id$
- * @package system.caching
- * @since 1.0
+ * @since 2.0
  */
 class CDummyCache extends CApplicationComponent implements ICache, ArrayAccess
 {
@@ -36,7 +35,7 @@ class CDummyCache extends CApplicationComponent implements ICache, ArrayAccess
 	{
 		parent::init();
 		if($this->keyPrefix===null)
-			$this->keyPrefix=Yii::app()->getId();
+			$this->keyPrefix=\Yii::$application->getId();
 	}
 
 	/**
diff --git a/framework/caching/EAcceleratorCache.php b/framework/caching/EAcceleratorCache.php
index 99be8be..ead2f04 100644
--- a/framework/caching/EAcceleratorCache.php
+++ b/framework/caching/EAcceleratorCache.php
@@ -2,12 +2,14 @@
 /**
  * CEAcceleratorCache class file
  *
- * @author Steffen Dietz <steffo.dietz[at]googlemail[dot]com>
  * @link http://www.yiiframework.com/
- * @copyright Copyright &copy; 2008-2011 Yii Software LLC
+ * @copyright Copyright &copy; 2008-2012 Yii Software LLC
  * @license http://www.yiiframework.com/license/
  */
 
+namespace yii\caching;
+
+
 /**
  * CEAcceleratorCache implements a cache application module based on {@link http://eaccelerator.net/ eaccelerator}.
  *
@@ -18,9 +20,8 @@
  * Please note that as of v0.9.6, eAccelerator no longer supports data caching.
  * This means if you still want to use this component, your eAccelerator should be of 0.9.5.x or lower version.
  *
- * @author Steffen Dietz <steffo.dietz[at]googlemail[dot]com>
- * @version $Id$
- * @package system.caching
+ * @author Qiang Xue <qiang.xue@gmail.com>
+ * @since 2.0
  */
 class CEAcceleratorCache extends CCache
 {
diff --git a/framework/caching/ExpressionDependency.php b/framework/caching/ExpressionDependency.php
index 9771b68..032ec32 100644
--- a/framework/caching/ExpressionDependency.php
+++ b/framework/caching/ExpressionDependency.php
@@ -2,12 +2,13 @@
 /**
  * CExpressionDependency class file.
  *
- * @author Qiang Xue <qiang.xue@gmail.com>
  * @link http://www.yiiframework.com/
- * @copyright Copyright &copy; 2008-2011 Yii Software LLC
+ * @copyright Copyright &copy; 2008-2012 Yii Software LLC
  * @license http://www.yiiframework.com/license/
  */
 
+namespace yii\caching;
+
 /**
  * CExpressionDependency represents a dependency based on the result of a PHP expression.
  *
@@ -17,9 +18,7 @@
  * the same as the one evaluated when storing the data to cache.
  *
  * @author Qiang Xue <qiang.xue@gmail.com>
- * @version $Id$
- * @package system.caching.dependencies
- * @since 1.0
+ * @since 2.0
  */
 class CExpressionDependency extends CCacheDependency
 {
diff --git a/framework/caching/FileCache.php b/framework/caching/FileCache.php
index 19af687..9de4b7f 100644
--- a/framework/caching/FileCache.php
+++ b/framework/caching/FileCache.php
@@ -2,12 +2,13 @@
 /**
  * CFileCache class file
  *
- * @author Qiang Xue <qiang.xue@gmail.com>
  * @link http://www.yiiframework.com/
- * @copyright Copyright &copy; 2008-2011 Yii Software LLC
+ * @copyright Copyright &copy; 2008-2012 Yii Software LLC
  * @license http://www.yiiframework.com/license/
  */
 
+namespace yii\caching;
+
 /**
  * CFileCache provides a file-based caching mechanism.
  *
@@ -21,8 +22,7 @@
  * when storing a piece of data in the cache. Defaults to 100, meaning 0.01% chance.
  *
  * @author Qiang Xue <qiang.xue@gmail.com>
- * @version $Id$
- * @package system.caching
+ * @since 2.0
  */
 class CFileCache extends CCache
 {
@@ -56,7 +56,7 @@ class CFileCache extends CCache
 	{
 		parent::init();
 		if($this->cachePath===null)
-			$this->cachePath=Yii::app()->getRuntimePath().DIRECTORY_SEPARATOR.'cache';
+			$this->cachePath=\Yii::$application->getRuntimePath().DIRECTORY_SEPARATOR.'cache';
 		if(!is_dir($this->cachePath))
 			mkdir($this->cachePath,0777,true);
 	}
diff --git a/framework/caching/FileDependency.php b/framework/caching/FileDependency.php
index 928fe1f..4293057 100644
--- a/framework/caching/FileDependency.php
+++ b/framework/caching/FileDependency.php
@@ -2,12 +2,14 @@
 /**
  * CFileCacheDependency class file.
  *
- * @author Qiang Xue <qiang.xue@gmail.com>
  * @link http://www.yiiframework.com/
- * @copyright Copyright &copy; 2008-2011 Yii Software LLC
+ * @copyright Copyright &copy; 2008-2012 Yii Software LLC
  * @license http://www.yiiframework.com/license/
  */
 
+namespace yii\caching;
+
+
 /**
  * CFileCacheDependency represents a dependency based on a file's last modification time.
  *
@@ -17,9 +19,7 @@
  * last modification time remains unchanged.
  *
  * @author Qiang Xue <qiang.xue@gmail.com>
- * @version $Id$
- * @package system.caching.dependencies
- * @since 1.0
+ * @since 2.0
  */
 class CFileCacheDependency extends CCacheDependency
 {
diff --git a/framework/caching/MemCache.php b/framework/caching/MemCache.php
index 0e1eb12..18586a8 100644
--- a/framework/caching/MemCache.php
+++ b/framework/caching/MemCache.php
@@ -2,12 +2,13 @@
 /**
  * CMemCache class file
  *
- * @author Qiang Xue <qiang.xue@gmail.com>
  * @link http://www.yiiframework.com/
- * @copyright Copyright &copy; 2008-2011 Yii Software LLC
+ * @copyright Copyright &copy; 2008-2012 Yii Software LLC
  * @license http://www.yiiframework.com/license/
  */
 
+namespace yii\caching;
+
 /**
  * CMemCache implements a cache application component based on {@link http://memcached.org/ memcached}.
  *
@@ -55,9 +56,7 @@
  * @property array $servers List of memcache server configurations. Each element is a {@link CMemCacheServerConfiguration}.
  *
  * @author Qiang Xue <qiang.xue@gmail.com>
- * @version $Id$
- * @package system.caching
- * @since 1.0
+ * @since 2.0
  */
 class CMemCache extends CCache
 {
diff --git a/framework/caching/WinCache.php b/framework/caching/WinCache.php
index 8def58d..f269c73 100644
--- a/framework/caching/WinCache.php
+++ b/framework/caching/WinCache.php
@@ -2,12 +2,13 @@
 /**
  * CWinCache class file
  *
- * @author Alexander Makarov <sam@rmcreative.ru>
  * @link http://www.yiiframework.com/
- * @copyright Copyright &copy; 2008-2011 Yii Software LLC
+ * @copyright Copyright &copy; 2008-2012 Yii Software LLC
  * @license http://www.yiiframework.com/license/
  */
 
+namespace yii\caching;
+
 /**
  * CWinCache implements a cache application component based on {@link http://www.iis.net/expand/wincacheforphp WinCache}.
  *
@@ -15,10 +16,8 @@
  *
  * See {@link CCache} manual for common cache operations that are supported by CWinCache.
  *
- * @author Alexander Makarov <sam@rmcreative.ru>
- * @version $Id$
- * @package system.caching
- * @since 1.1.2
+ * @author Qiang Xue <qiang.xue@gmail.com>
+ * @since 2.0
  */
 class CWinCache extends CCache {
 	/**
diff --git a/framework/caching/XCache.php b/framework/caching/XCache.php
index 62cc608..0814cb7 100644
--- a/framework/caching/XCache.php
+++ b/framework/caching/XCache.php
@@ -2,12 +2,13 @@
 /**
  * CXCache class file
  *
- * @author Wei Zhuo <weizhuo[at]gmail[dot]com>
  * @link http://www.yiiframework.com/
- * @copyright Copyright &copy; 2008-2011 Yii Software LLC
+ * @copyright Copyright &copy; 2008-2012 Yii Software LLC
  * @license http://www.yiiframework.com/license/
  */
 
+namespace yii\caching;
+
 /**
  * CXCache implements a cache application module based on {@link http://xcache.lighttpd.net/ xcache}.
  *
@@ -16,9 +17,8 @@
  *
  * See {@link CCache} manual for common cache operations that are supported by CXCache.
  *
- * @author Wei Zhuo <weizhuo[at]gmail[dot]com>
- * @version $Id$
- * @package system.caching
+ * @author Qiang Xue <qiang.xue@gmail.com>
+ * @since 2.0
  */
 class CXCache extends CCache
 {
diff --git a/framework/caching/ZendDataCache.php b/framework/caching/ZendDataCache.php
index 9804717..57402a2 100644
--- a/framework/caching/ZendDataCache.php
+++ b/framework/caching/ZendDataCache.php
@@ -2,12 +2,13 @@
 /**
  * CZendDataCache class file
  *
- * @author Steffen Dietz <steffo.dietz[at]googlemail[dot]com>
  * @link http://www.yiiframework.com/
- * @copyright Copyright &copy; 2008-2011 Yii Software LLC
+ * @copyright Copyright &copy; 2008-2012 Yii Software LLC
  * @license http://www.yiiframework.com/license/
  */
 
+namespace yii\caching;
+
 /**
  * CZendDataCache implements a cache application module based on the Zend Data Cache
  * delivered with {@link http://www.zend.com/en/products/server/ ZendServer}.
@@ -16,9 +17,8 @@
  *
  * See {@link CCache} manual for common cache operations that are supported by CZendDataCache.
  *
- * @author Steffen Dietz <steffo.dietz[at]googlemail[dot]com>
- * @version $Id$
- * @package system.caching
+ * @author Qiang Xue <qiang.xue@gmail.com>
+ * @since 2.0
  */
 class CZendDataCache extends CCache
 {
diff --git a/framework/console/commands/MigrateController.php b/framework/console/commands/MigrateController.php
index ad02322..681dc98 100644
--- a/framework/console/commands/MigrateController.php
+++ b/framework/console/commands/MigrateController.php
@@ -416,7 +416,7 @@ class MigrateCommand extends CConsoleCommand
 	{
 		if($this->_db!==null)
 			return $this->_db;
-		else if(($this->_db=Yii::app()->getComponent($this->connectionID)) instanceof CDbConnection)
+		else if(($this->_db=\Yii::$application->getComponent($this->connectionID)) instanceof CDbConnection)
 			return $this->_db;
 		else
 			die("Error: CMigrationCommand.connectionID '{$this->connectionID}' is invalid. Please make sure it refers to the ID of a CDbConnection application component.\n");
diff --git a/framework/console/commands/ShellController.php b/framework/console/commands/ShellController.php
index f6cf153..2fcf554 100644
--- a/framework/console/commands/ShellController.php
+++ b/framework/console/commands/ShellController.php
@@ -112,7 +112,7 @@ EOD;
 		if(($_path_=@getenv('YIIC_SHELL_COMMAND_PATH'))!==false)
 			$_runner_->addCommands($_path_);
 		$_commands_=$_runner_->commands;
-		$log=Yii::app()->log;
+		$log=\Yii::$application->log;
 
 		while(($_line_=$this->prompt("\n>>"))!==false)
 		{
diff --git a/framework/web/AssetManager.php b/framework/web/AssetManager.php
index 452317a..2028a1c 100644
--- a/framework/web/AssetManager.php
+++ b/framework/web/AssetManager.php
@@ -97,7 +97,7 @@ class CAssetManager extends CApplicationComponent
 	{
 		if($this->_basePath===null)
 		{
-			$request=Yii::app()->getRequest();
+			$request=\Yii::$application->getRequest();
 			$this->setBasePath(dirname($request->getScriptFile()).DIRECTORY_SEPARATOR.self::DEFAULT_BASEPATH);
 		}
 		return $this->_basePath;
@@ -125,7 +125,7 @@ class CAssetManager extends CApplicationComponent
 	{
 		if($this->_baseUrl===null)
 		{
-			$request=Yii::app()->getRequest();
+			$request=\Yii::$application->getRequest();
 			$this->setBaseUrl($request->getBaseUrl().'/'.self::DEFAULT_BASEPATH);
 		}
 		return $this->_baseUrl;
diff --git a/framework/web/Request.php b/framework/web/Request.php
index a03984e..08bc202 100644
--- a/framework/web/Request.php
+++ b/framework/web/Request.php
@@ -130,7 +130,7 @@ class CHttpRequest extends CApplicationComponent
 		}
 
 		if($this->enableCsrfValidation)
-			Yii::app()->attachEventHandler('onBeginRequest',array($this,'validateCsrfToken'));
+			\Yii::$application->attachEventHandler('onBeginRequest',array($this,'validateCsrfToken'));
 	}
 
 
@@ -762,7 +762,7 @@ class CHttpRequest extends CApplicationComponent
 			$url=$this->getHostInfo().$url;
 		header('Location: '.$url, true, $statusCode);
 		if($terminate)
-			Yii::app()->end();
+			\Yii::$application->end();
 	}
 
 	/**
@@ -816,7 +816,7 @@ class CHttpRequest extends CApplicationComponent
 		{
 			// clean up the application first because the file downloading could take long time
 			// which may cause timeout of some resources (such as DB connection)
-			Yii::app()->end(0,false);
+			\Yii::$application->end(0,false);
 			echo $content;
 			exit(0);
 		}
@@ -858,7 +858,7 @@ class CHttpRequest extends CApplicationComponent
 	 * <b>Example</b>:
 	 * <pre>
 	 * <?php
-	 *    Yii::app()->request->xSendFile('/home/user/Pictures/picture1.jpg',array(
+	 *    \Yii::$application->request->xSendFile('/home/user/Pictures/picture1.jpg',array(
 	 *        'saveName'=>'image1.jpg',
 	 *        'mimeType'=>'image/jpeg',
 	 *        'terminate'=>false,
@@ -906,7 +906,7 @@ class CHttpRequest extends CApplicationComponent
 		header(trim($options['xHeader']).': '.$filePath);
 
 		if(!isset($options['terminate']) || $options['terminate'])
-			Yii::app()->end();
+			\Yii::$application->end();
 	}
 
 	/**
@@ -1029,7 +1029,7 @@ class CCookieCollection extends CMap
 		$cookies=array();
 		if($this->_request->enableCookieValidation)
 		{
-			$sm=Yii::app()->getSecurityManager();
+			$sm=\Yii::$application->getSecurityManager();
 			foreach($_COOKIE as $name=>$value)
 			{
 				if(is_string($value) && ($value=$sm->validateData($value))!==false)
@@ -1090,7 +1090,7 @@ class CCookieCollection extends CMap
 	{
 		$value=$cookie->value;
 		if($this->_request->enableCookieValidation)
-			$value=Yii::app()->getSecurityManager()->hashData(serialize($value));
+			$value=\Yii::$application->getSecurityManager()->hashData(serialize($value));
 		if(version_compare(PHP_VERSION,'5.2.0','>='))
 			setcookie($cookie->name,$value,$cookie->expire,$cookie->path,$cookie->domain,$cookie->secure,$cookie->httpOnly);
 		else
diff --git a/framework/web/Sort.php b/framework/web/Sort.php
index c8ba5fa..ea20f22 100644
--- a/framework/web/Sort.php
+++ b/framework/web/Sort.php
@@ -303,7 +303,7 @@ class CSort extends CComponent
 		else
 			$directions=array($attribute=>$descending);
 
-		$url=$this->createUrl(Yii::app()->getController(),$directions);
+		$url=$this->createUrl(\Yii::$application->getController(),$directions);
 
 		return $this->createLink($attribute,$label,$url,$htmlOptions);
 	}
diff --git a/framework/web/Theme.php b/framework/web/Theme.php
index 337e968..5dcd601 100644
--- a/framework/web/Theme.php
+++ b/framework/web/Theme.php
@@ -126,7 +126,7 @@ class CTheme extends CComponent
 				$module=$module->getParentModule();
 			}
 			if($module===null)
-				$layoutName=Yii::app()->layout;
+				$layoutName=\Yii::$application->layout;
 			else
 			{
 				$layoutName=$module->layout;
diff --git a/framework/web/ThemeManager.php b/framework/web/ThemeManager.php
index 0cf7a5f..550f4a1 100644
--- a/framework/web/ThemeManager.php
+++ b/framework/web/ThemeManager.php
@@ -96,7 +96,7 @@ class CThemeManager extends CApplicationComponent
 	public function getBasePath()
 	{
 		if($this->_basePath===null)
-			$this->setBasePath(dirname(Yii::app()->getRequest()->getScriptFile()).DIRECTORY_SEPARATOR.self::DEFAULT_BASEPATH);
+			$this->setBasePath(dirname(\Yii::$application->getRequest()->getScriptFile()).DIRECTORY_SEPARATOR.self::DEFAULT_BASEPATH);
 		return $this->_basePath;
 	}
 
@@ -117,7 +117,7 @@ class CThemeManager extends CApplicationComponent
 	public function getBaseUrl()
 	{
 		if($this->_baseUrl===null)
-			$this->_baseUrl=Yii::app()->getBaseUrl().'/'.self::DEFAULT_BASEPATH;
+			$this->_baseUrl=\Yii::$application->getBaseUrl().'/'.self::DEFAULT_BASEPATH;
 		return $this->_baseUrl;
 	}
 
diff --git a/framework/web/UrlManager.php b/framework/web/UrlManager.php
index 755529e..2acae54 100644
--- a/framework/web/UrlManager.php
+++ b/framework/web/UrlManager.php
@@ -214,7 +214,7 @@ class CUrlManager extends CApplicationComponent
 	{
 		if(empty($this->rules) || $this->getUrlFormat()===self::GET_FORMAT)
 			return;
-		if($this->cacheID!==false && ($cache=Yii::app()->getComponent($this->cacheID))!==null)
+		if($this->cacheID!==false && ($cache=\Yii::$application->getComponent($this->cacheID))!==null)
 		{
 			$hash=md5(serialize($this->rules));
 			if(($data=$cache->get(self::CACHE_KEY))!==false && isset($data[1]) && $data[1]===$hash)
@@ -466,9 +466,9 @@ class CUrlManager extends CApplicationComponent
 		else
 		{
 			if($this->showScriptName)
-				$this->_baseUrl=Yii::app()->getRequest()->getScriptUrl();
+				$this->_baseUrl=\Yii::$application->getRequest()->getScriptUrl();
 			else
-				$this->_baseUrl=Yii::app()->getRequest()->getBaseUrl();
+				$this->_baseUrl=\Yii::$application->getRequest()->getBaseUrl();
 			return $this->_baseUrl;
 		}
 	}
@@ -767,7 +767,7 @@ class CUrlRule extends CBaseUrlRule
 
 		if($this->hasHostInfo)
 		{
-			$hostInfo=Yii::app()->getRequest()->getHostInfo();
+			$hostInfo=\Yii::$application->getRequest()->getHostInfo();
 			if(stripos($url,$hostInfo)===0)
 				$url=substr($url,strlen($hostInfo));
 		}