diff --git a/docs/api/base/Component.md b/docs/api/base/Component.md
index 89b8c0b..01ef462 100644
--- a/docs/api/base/Component.md
+++ b/docs/api/base/Component.md
@@ -1,3 +1,5 @@
+Component is the base class that implements the *property*, *event* and *behavior* features.
+
 Component provides the *event* and *behavior* features, in addition to the *property* feature which is implemented in
 its parent class [[Object]].
 
@@ -7,20 +9,20 @@ is triggered (i.e. comment will be added), our custom code will be executed.
 
 An event is identified by a name that should be unique within the class it is defined at. Event names are *case-sensitive*.
 
-One or multiple PHP callbacks, called *event handlers*, could be attached to an event. You can call [[trigger()]] to
+One or multiple PHP callbacks, called *event handlers*, can be attached to an event. You can call [[trigger()]] to
 raise an event. When an event is raised, the event handlers will be invoked automatically in the order they were
 attached.
 
 To attach an event handler to an event, call [[on()]]:
 
 ~~~
-$comment->on('add', function($event) {
+$post->on('update', function($event) {
     // send email notification
 });
 ~~~
 
-In the above, we attach an anonymous function to the "add" event of the comment.
-Valid event handlers include:
+In the above, an anonymous function is attached to the "update" event of the post. You may attach
+the following types of event handlers:
 
 - anonymous function: `function($event) { ... }`
 - object method: `array($object, 'handleAdd')`
@@ -35,8 +37,8 @@ function foo($event)
 
 where `$event` is an [[Event]] object which includes parameters associated with the event.
 
-You can also attach an event handler to an event when configuring a component with a configuration array. The syntax is
-like the following:
+You can also attach a handler to an event when configuring a component with a configuration array.
+The syntax is like the following:
 
 ~~~
 array(
@@ -46,15 +48,13 @@ array(
 
 where `on add` stands for attaching an event to the `add` event.
 
-You can call [[getEventHandlers()]] to retrieve all event handlers that are attached to a specified event. Because this
-method returns a [[Vector]] object, we can manipulate this object to attach/detach event handlers, or adjust their
-relative orders.
+Sometimes, you may want to associate extra data with an event handler when you attach it to an event
+and then access it when the handler is invoked. You may do so by
 
 ~~~
-$handlers = $comment->getEventHandlers('add');
-$handlers->insertAt(0, $callback); // attach a handler as the first one
-$handlers[] = $callback;           // attach a handler as the last one
-unset($handlers[0]);               // detach the first handler
+$post->on('update', function($event) {
+    // the data can be accessed via $event->data
+}, $data);
 ~~~
 
 
diff --git a/docs/api/base/Object.md b/docs/api/base/Object.md
index a2cea6c..1b9fca0 100644
--- a/docs/api/base/Object.md
+++ b/docs/api/base/Object.md
@@ -1,3 +1,5 @@
+Object is the base class that implements the *property* feature.
+
 A property is defined by a getter method (e.g. `getLabel`), and/or a setter method (e.g. `setLabel`). For example,
 the following getter and setter methods define a property named `label`:
 
@@ -30,4 +32,30 @@ $object->label = 'abc';
 If a property has only a getter method and has no setter method, it is considered as *read-only*. In this case, trying
 to modify the property value will cause an exception.
 
-One can call [[hasProperty]], [[canGetProperty]] and/or [[canSetProperty]] to check the existence of a property.
+One can call [[hasProperty()]], [[canGetProperty()]] and/or [[canSetProperty()]] to check the existence of a property.
+
+
+Besides the property feature, Object also introduces an important object initialization life cycle. In particular,
+creating an new instance of Object or its derived class will involve the following life cycles sequentially:
+
+1. the class constructor is invoked;
+2. object properties are initialized according to the given configuration;
+3. the `init()` method is invoked.
+
+In the above, both Step 2 and 3 occur at the end of the class constructor. It is recommended that
+you perform object initialization in the `init()` method because at that stage, the object configuration
+is already applied.
+
+In order to ensure the above life cycles, if a child class of Object needs to override the constructor,
+it should be done like the following:
+
+~~~
+public function __construct($param1, $param2, ..., $config = array())
+{
+    ...
+    parent::__construct($config);
+}
+~~~
+
+That is, a `$config` parameter (defaults to `array()`) should be declared as the last parameter
+of the constructor, and the parent implementation should be called at the end of the constructor.
diff --git a/docs/code_style.md b/docs/code_style.md
deleted file mode 100644
index 92a934b..0000000
--- a/docs/code_style.md
+++ /dev/null
@@ -1,328 +0,0 @@
-Yii2 code standard
-==================
-
-This code standard is used for all the Yii2 core classes and can be applied to
-your application in order to achieve consistency among your team. Also it will
-help in case you want to opensource code.
-
-PHP file formatting
--------------------
-
-### General
-
-- Do not end file with `?>` if it contains PHP code only.
-- Do not use `<?`. Use `<?php` instead.
-- Files should be encoded in UTF-8.
-- Any file that contains PHP code should end with the extension `.php`.
-- Do not add trailing spaces to the end of the lines.
-
-#### Indentation
-
-All code must be indented with tabs. That includes both PHP and JavaScript code.
-
-#### Maximum Line Length
-
-We're not strictly limiting maximum line length but sticking to 80 characters
-where possible.
-
-### PHP types
-
-All PHP types and values should be used lowercase. That includes `true`, `false`,
-`null` and `array`.
-
-### Strings
-
-- If string doesn't contain variables or single quotes, use single quotes.
-
-~~~
-$str = 'Like this.';
-~~~
-
-- If string contains single quotes you can use double quotes to avoid extra escaping.
-- You can use the following forms of variable substitution:
-
-~~~
-$str1 = "Hello $username!";
-$str2 = "Hello {$username}!";
-~~~
-
-The following is not permitted:
-
-~~~
-$str3 = "Hello ${username}!";
-~~~
-
-### String concatenation
-
-Add spaces around dot when concatenating strings:
-
-~~~
-$name = 'Yii' . ' Framework';
-~~~
-
-When string is long format is the following:
-
-~~~
-$sql = "SELECT *"
-     . "FROM `post` "
-     . "WHERE `id` = 121 ";
-~~~
-
-
-### Numerically indexed arrays
-
-- Do not use negative numbers as array indexes.
-
-Use the following formatting when declaring array:
-
-~~~
-$arr = array(3, 14, 15, 'Yii', 'Framework');
-~~~
-
-If there are too many elements for a single line:
-
-~~~
-$arr = array(
-	3, 14, 15,
-	92, 6, $test,
-	'Yii', 'Framework',
-);
-~~~
-
-### Associative arrays
-
-Use the following format for associative arrays:
-
-~~~
-$config = array(
-	'name'  => 'Yii',
-	'options' => array(
-		'usePHP' => true,
-	),
-);
-~~~
-
-### Classes
-
-- Classes should be named using `CamelCase`.
-- The brace should always be written on the line underneath the class name.
-- Every class must have a documentation block that conforms to the PHPDoc.
-- All code in a class must be indented with a single tab.
-- There should be only one class in a single PHP file.
-- All classes should be namespaced.
-- Class name should match file name. Class namespace should match directory structure.
-
-~~~
-/**
- * Documentation
- */
-class MyClass extends \yii\Object implements MyInterface
-{
-	// code
-}
-~~~
-
-
-### Class members and variables
-
-- When declaring public class members specify `public` keyword explicitly.
-- Variables should be declared at the top of the class before any method declarations.
-- Private and protected variables should be named like `$_varName`.
-- Public class members and standalone variables should be named using `$camelCase`
-  with first letter lowercase.
-- Use descriptive names. Variables such as `$i` and `$j` are better not to be used.
-
-### Constants
-
-Both class level constants and global constants should be named in uppercase. Words
-are separated by underscore.
-
-~~~
-class User {
-	const STATUS_ACTIVE = 1;
-	const STATUS_BANNED = 2;
-}
-~~~
-
-It's preferable to define class level constants rather than global ones.
-
-### Functions and methods
-
-- Functions and methods should be named using `camelCase` with first letter lowercase.
-- Name should be descriptive by itself indicating the purpose of the function.
-- Class methods should always declare visibility using `private`, `protected` and
-  `public` modifiers. `var` is not allowed.
-- Opening brace of a function should be on the line after the function declaration.
-
-~~~
-/**
- * Documentation
- */
-class Foo
-{
-	/**
-	 * Documentation
-	 */
-	public function bar()
-	{
-		// code
-		return $value;
-	}
-}
-~~~
-
-Use type hinting where possible:
-
-~~~
-public function __construct(CDbConnection $connection)
-{
-	$this->connection = $connection;
-}
-~~~
-
-### Function and method calls
-
-~~~
-doIt(2, 3);
-
-doIt(array(
-	'a' => 'b',
-));
-
-doIt('a', array(
-	'a' => 'b',
-));
-~~~
-
-### Control statements
-
-- Control statement condition must have single space before and after parenthesis.
-- Operators inside of parenthesis should be separated by spaces.
-- Opening brace is on the same line.
-- Closing brace is on a new line.
-- Always use braces for single line statements.
-
-~~~
-if ($event === null) {
-	return new Event();
-} elseif ($event instanceof CoolEvent) {
-	return $event->instance();
-} else {
-	return null;
-}
-
-// the following is NOT allowed:
-if(!$model)
-	throw new Exception('test');
-~~~
-
-
-### Switch
-
-Use the following formatting for switch:
-
-~~~
-switch ($this->phpType) {
-	case 'string':
-		$a = (string)$value;
-		break;
-	case 'integer':
-	case 'int':
-		$a = (integer)$value;
-		break;
-	case 'boolean':
-		$a = (boolean)$value;
-		break;
-	default:
-		$a = null;
-}
-~~~
-
-### Code documentation
-
-- Refer ot [phpDoc](http://phpdoc.org/) for documentation syntax.
-- Code without documentation is not allowed.
-- All class files must contain a "file-level" docblock at the top of each file
-  and a "class-level" docblock immediately above each class.
-- There is no need to use `@return` if method does return nothing.
-
-#### File
-
-~~~
-<?php
-/**
- * @link http://www.yiiframework.com/
- * @copyright Copyright (c) 2008 Yii Software LLC
- * @license http://www.yiiframework.com/license/
- */
-~~~
-
-#### Class
-
-~~~
-/**
- * Component is the base class that provides the *property*, *event* and *behavior* features.
- *
- * @include @yii/docs/base-Component.md
- *
- * @author Qiang Xue <qiang.xue@gmail.com>
- * @since 2.0
- */
-class Component extends \yii\base\Object
-~~~
-
-
-#### Function / method
-
-~~~
-/**
- * Returns the list of attached event handlers for an event.
- * You may manipulate the returned [[Vector]] object by adding or removing handlers.
- * For example,
- *
- * ~~~
- * $component->getEventHandlers($eventName)->insertAt(0, $eventHandler);
- * ~~~
- *
- * @param string $name the event name
- * @return Vector list of attached event handlers for the event
- * @throws Exception if the event is not defined
- */
-public function getEventHandlers($name)
-{
-	if (!isset($this->_e[$name])) {
-		$this->_e[$name] = new Vector;
-	}
-	$this->ensureBehaviors();
-	return $this->_e[$name];
-}
-~~~
-
-#### Comments
-
-- One-line comments should be started with `//` and not `#`.
-- One-line comment should be on its own line.
-
-Yii application naming conventions
-----------------------------------
-
-
-
-Other library and framework standards
--------------------------------------
-
-It's good to be consistent with other frameworks and libraries whose components
-will be possibly used with Yii2. That's why when there are no objective reasons
-to use different style we should use one that's common among most of the popular
-libraries and frameworks.
-
-That's not only about PHP but about JavaScript as well. Since we're using jQuery
-a lot it's better to be consistent with its style as well.
-
-Application style consistency is much more important than consistency with other frameworks and libraries.
-
-- [Symfony 2](http://symfony.com/doc/current/contributing/code/standards.html)
-- [Zend Framework 1](http://framework.zend.com/manual/en/coding-standard.coding-style.html)
-- [Zend Framework 2](http://framework.zend.com/wiki/display/ZFDEV2/Coding+Standards)
-- [Pear](http://pear.php.net/manual/en/standards.php)
-- [jQuery](http://docs.jquery.com/JQuery_Core_Style_Guidelines)
\ No newline at end of file
diff --git a/docs/full_2011_11_12.png b/docs/full_2011_11_12.png
deleted file mode 100644
index ef50fcb..0000000
Binary files a/docs/full_2011_11_12.png and /dev/null differ
diff --git a/docs/hierarchy_2011_11_12.png b/docs/hierarchy_2011_11_12.png
deleted file mode 100644
index b5f8abc..0000000
Binary files a/docs/hierarchy_2011_11_12.png and /dev/null differ
diff --git a/docs/review_2011_11_12_alex.md b/docs/review_2011_11_12_alex.md
deleted file mode 100644
index 38ffda2..0000000
--- a/docs/review_2011_11_12_alex.md
+++ /dev/null
@@ -1,192 +0,0 @@
-Alex's Code Review, 2011.11.12
-==============================
-
-Overall hierarchy
-------------------
-
-Generally is OK. Like that `Object` and `Component` are now separated.
-I've generated 2 diagrams under `docs/` to see it better as a whole.
-
-> The purpose of separating `Object` from `Component` is to make `Object`
-> a super-light base class that supports properties defined by getter/setters.
-> Note that `Component` is a bit of heavy because it uses two extra member
-> variables to support events and behaviors.
-
-
-Object
-------
-
-### property feature
-
-Is it OK that `canGetProperty` and `canSetProperty` will return `false` for real
-class members?
-
-> Added $checkVar parameter
-
-### callbacks and expressions
-
-We're using 5.3. What's the reason to support `eval()` in `evaluateExpression` if
-we have anonymous functions? Is that for storing code as string inside of DB (RBAC)?
-
-If we're going to get rid of `eval()`, cosider remaning method to something about callback.
-If not then we definitely need to use anonymous functions in API docs and the guide
-where possible.
-
-> The purpose of evaluateExpression() is to provide a way of evaluating a PHP expression
-> in the context of an object. Will remove it before release if we find no use of it.
-
->> mdomba:
->> As eval() is controversial, and anonymous functions can replace all Yii 1 usage of eval()
->> how about removing it from the beginning and add it only if we find it necessary.
->> This way we would not be tempted to stick with eval() and will be forced to first try to find alternatives
-
-### Object::create()
-
-#### `__construct` issue
-
-Often a class doesn't have `__construct` implementation and `stdClass` doesn't have
-default one either but Object::create() always expects constructor to be
-defined. See `ObjectTest`. Either `method_exists` call or `Object::__construct` needed.
-
-> Added Object::__construct.
-
-#### How to support object factory like we do with CWidgetFactory?
-
-~~~
-class ObjectConfig
-{
-	public function configure($class)
-	{
-		$config = $this->load($class);
-		// apply config to $class
-	}
-
-	private function load($class)
-	{
-		// get class properties from a config file
-		// in this method we need to walk all the
-		// inheritance hierarchy down to Object itself
-		return array(
-			'property' => 'value',
-			// …
-		);
-	}
-}
-~~~
-
-Then we need to add `__construct` to `Object` (or implement `Initalbe`):
-
-~~~
-class Object
-{
-	public function __construct()
-	{
-		$conf = new ObjectConfig();
-		$conf->configure($this);
-	}
-}
-~~~
-
-This way we'll be able to set defaults for any object.
-
-> The key issue here is about how to process the config file. Clearly, we cannot
-> do this for every type of component because it would mean an extra file access
-> for every component type
-
-#### Do we need to support lazy class injection?
-
-Currently there's no way to lazy-inject class into another class property via
-config. Do we need it? If yes then we can probably extend component config to support
-the following:
-
-~~~
-class Foo extends Object
-{
-	public $prop;
-}
-
-class Bar extends Object
-{
-	public $prop;
-}
-
-$config = array(
-	'prop' => array(
-		'class' => 'Bar',
-		'prop' => 'Hello!',
-	),
-);
-
-$foo = Foo::create($config);
-echo $foo->bar->prop;
-// will output Hello!
-~~~
-
-Should it support infinite nesting level?
-
-> I don't think we need this. Foo::$prop cannot be an object unless it needs it to be.
-> In that case, it can be defined with a setter in which it can handle the object creation
-> based on a configuration array. This is a bit inconvenient, but I think such usage is
-> not very common.
-
-### Why `Event` is `Object`?
-
-There's no need to extend from `Object`. Is there a plan to use `Object` features
-later?
-
-> To use properties defined via getter/setter.
-
-
-Behaviors
----------
-
-Overall I wasn't able to use behaviors. See `BehaviorTest`.
-
-### Should behaviors be able to define events for owner components?
-
-Why not? Should be a very good feature in order to make behaviors customizable.
-
-> It's a bit hard to implement it efficiently. I tend not to support it for now
-> unless enough people are requesting for it.
-
-### Multiple behaviors can be attached to the same component
-
-What if we'll have multiple methods / properties / events with the same name?
-
-> The first one takes precedence. This is the same as we do in 1.1.
-
-### How to use Behavior::attach?
-
-Looks like it is used by `Component::attachBehavior` but can't be used without it.
-Why it's public then? Can we move it to `Component?`
-
-> It's public because it is called by Component. It is in Behavior such that
-> it can be overridden by behavior classes to customize the attach process.
-
-Events
-------
-
-Class itself looks OK. Component part is OK as well but I've not tested
-it carefully. Overall it seems concept is the same as in Yii1.
-
-### Event declaration: the on-method is mostly repetitive for every event. Should we choose a different way of declaring events?
-
-Maybe. People complained previously about too many code for event declaration.
-
-### Should we implement some additional event mechanism, such as global events?
-
-Why use two different implementations in a single application?
-
-Exceptions
-----------
-
-- Should we convert all errors, warnings and notices to exceptions?
-
-> I think not. We used to do this in early versions of 1.0. We found sometimes
-> very mysterious things would happen which makes error fixing harder rather than
-> easier.
-
-Coding style
-------------
-
-See `docs/code_style.md`.
\ No newline at end of file
diff --git a/framework/YiiBase.php b/framework/YiiBase.php
index e81a288..6df998b 100644
--- a/framework/YiiBase.php
+++ b/framework/YiiBase.php
@@ -46,8 +46,9 @@ class YiiBase
 {
 	/**
 	 * @var array class map used by the Yii autoloading mechanism.
-	 * The array keys are the class names, and the array values are the corresponding class file paths.
-	 * This property mainly affects how [[autoload]] works.
+	 * The array keys are the class names (without leading backslashes), and the array values
+	 * are the corresponding class file paths (or path aliases). This property mainly affects
+	 * how [[autoload()]] works.
 	 * @see import
 	 * @see autoload
 	 */
@@ -113,7 +114,7 @@ class YiiBase
 	 * includes the class file when the class is referenced in the code the first time.
 	 *
 	 * Importing a directory will add the directory to the front of the [[classPath]] array.
-	 * When [[autoload]] is loading an unknown class, it will search in the directories
+	 * When [[autoload()]] is loading an unknown class, it will search in the directories
 	 * specified in [[classPath]] to find the corresponding class file to include.
 	 * For this reason, if multiple directories are imported, the directories imported later
 	 * will take precedence in class file searching.
@@ -188,10 +189,10 @@ class YiiBase
 	 * it will be returned back without change.
 	 *
 	 * Note, this method does not ensure the existence of the resulting path.
-	 * @param string $alias alias
+	 * @param string $alias the alias to be translated.
 	 * @param boolean $throwException whether to throw an exception if the given alias is invalid.
 	 * If this is false and an invalid alias is given, false will be returned by this method.
-	 * @return string|boolean path corresponding to the alias, false if the root alias is not previously registered.
+	 * @return string|boolean the path corresponding to the alias, false if the root alias is not previously registered.
 	 * @throws InvalidParamException if the alias is invalid while $throwException is true.
 	 * @see setAlias
 	 */
@@ -225,13 +226,14 @@ class YiiBase
 	 * Note that this method neither checks the existence of the path nor normalizes the path.
 	 * Any trailing '/' and '\' characters in the path will be trimmed.
 	 *
-	 * @param string $alias alias to the path. The alias must start with '@'.
+	 * @param string $alias the alias name (e.g. "@yii"). It should start with a '@' character
+	 * and should NOT contain the forward slash "/" or the backward slash "\".
 	 * @param string $path the path corresponding to the alias. This can be
 	 *
 	 * - a directory or a file path (e.g. `/tmp`, `/tmp/main.txt`)
 	 * - a URL (e.g. `http://www.yiiframework.com`)
 	 * - a path alias (e.g. `@yii/base`). In this case, the path alias will be converted into the
-	 *   actual path first by calling [[getAlias]].
+	 *   actual path first by calling [[getAlias()]].
 	 *
 	 * @throws Exception if $path is an invalid alias
 	 * @see getAlias
@@ -268,48 +270,35 @@ class YiiBase
 	 */
 	public static function autoload($className)
 	{
-		if (isset(self::$classMap[$className])) {
-			include(self::$classMap[$className]);
-			return true;
-		}
+		$className = ltrim($className, '\\');
 
-		if (strpos($className, '\\') !== false) {
-			// namespaced class, e.g. yii\base\Component
-			// convert namespace to path alias, e.g. yii\base\Component to @yii/base/Component
-			$alias = '@' . str_replace('\\', '/', ltrim($className, '\\'));
-			if (($path = static::getAlias($alias, false)) !== false) {
-				$classFile = $path . '.php';
-			}
-		} elseif (($pos = strpos($className, '_')) !== false) {
-			// PEAR-styled class, e.g. PHPUnit_Framework_TestCase
-			// convert class name to path alias, e.g. PHPUnit_Framework_TestCase to @PHPUnit/Framework/TestCase
-			$alias = '@' . str_replace('_', '/', $className);
-			if (($path = static::getAlias($alias, false)) !== false) {
-				$classFile = $path . '.php';
+		if (isset(self::$classMap[$className])) {
+			$classFile = self::$classMap[$className];
+		} else {
+			if (($pos = strrpos($className, '\\')) !== false) {
+				// namespaced class, e.g. yii\base\Component
+				$classFile = str_replace('\\', '/', substr($className, 0, $pos + 1))
+					. str_replace('_', '/', substr($className, $pos + 1)) . '.php';
+			} else {
+				$classFile = str_replace('_', '/', $className) . '.php';
 			}
-		}
-
-		if (!isset($classFile)) {
-			// search in include paths
-			foreach (self::$classPath as $path) {
-				$path .= DIRECTORY_SEPARATOR . $className . '.php';
-				if (is_file($path)) {
-					$classFile = $path;
-					$alias = $className;
-				}
+			if (strpos($classFile, '/') !== false) {
+				// make it into a path alias
+				$classFile = '@' . $classFile;
 			}
 		}
 
-		if (isset($classFile, $alias) && is_file($classFile)) {
-			if (!YII_DEBUG || basename(realpath($classFile)) === basename($alias) . '.php') {
-				include($classFile);
+		$classFile = static::getAlias($classFile);
+		if ($classFile !== false && is_file($classFile)) {
+			include($classFile);
+			if (class_exists($className, false) || interface_exists($className, false)) {
 				return true;
 			} else {
-				throw new Exception("Class name '$className' does not match the class file '" . realpath($classFile) . "'. Have you checked their case sensitivity?");
+				throw new Exception("Unable to find '$className' in file: $classFile");
 			}
+		} else {
+			return false;
 		}
-
-		return false;
 	}
 
 	/**
@@ -371,6 +360,12 @@ class YiiBase
 			$class = static::import($class, true);
 		}
 
+		$class = ltrim($class, '\\');
+
+		if (isset(self::$objectConfig[$class])) {
+			$config = array_merge(self::$objectConfig[$class], $config);
+		}
+
 		if (($n = func_num_args()) > 1) {
 			/** @var $reflection \ReflectionClass */
 			if (isset($reflections[$class])) {
@@ -531,6 +526,6 @@ class YiiBase
 	 */
 	public static function t($message, $params = array(), $language = null)
 	{
-		return Yii::$app->getI18N()->translate($message, $params, $language);
+		return self::$app->getI18N()->translate($message, $params, $language);
 	}
 }
diff --git a/framework/base/ActionEvent.php b/framework/base/ActionEvent.php
index 7c5a40c..9507b12 100644
--- a/framework/base/ActionEvent.php
+++ b/framework/base/ActionEvent.php
@@ -22,7 +22,9 @@ class ActionEvent extends Event
 	 */
 	public $action;
 	/**
-	 * @var boolean whether to continue running the action.
+	 * @var boolean whether to continue running the action. Event handlers of
+	 * [[Controller::EVENT_BEFORE_ACTION]] may set this property to decide whether
+	 * to continue running the current action.
 	 */
 	public $isValid = true;
 
diff --git a/framework/base/Application.php b/framework/base/Application.php
index 9be1939..e1c1d60 100644
--- a/framework/base/Application.php
+++ b/framework/base/Application.php
@@ -87,9 +87,6 @@ class Application extends Module
 	 */
 	public $layout = 'main';
 
-	// todo
-	public $localeDataPath = '@yii/i18n/data';
-
 	private $_runtimePath;
 	private $_ended = false;
 
@@ -101,36 +98,42 @@ class Application extends Module
 
 	/**
 	 * Constructor.
-	 * @param string $id the ID of this application. The ID should uniquely identify the application from others.
-	 * @param string $basePath the base path of this application. This should point to
-	 * the directory containing all application logic, template and data.
-	 * @param array $config name-value pairs that will be used to initialize the object properties
+	 * @param array $config name-value pairs that will be used to initialize the object properties.
+	 * Note that the configuration must contain both [[id]] and [[basePath]].
+	 * @throws InvalidConfigException if either [[id]] or [[basePath]] configuration is missing.
 	 */
-	public function __construct($id, $basePath, $config = array())
+	public function __construct($config = array())
 	{
 		Yii::$app = $this;
-		$this->id = $id;
-		$this->setBasePath($basePath);
 
-		if (YII_ENABLE_ERROR_HANDLER) {
-			ini_set('display_errors', 0);
-			set_exception_handler(array($this, 'handleException'));
-			set_error_handler(array($this, 'handleError'), error_reporting());
+		if (!isset($config['id'])) {
+			throw new InvalidConfigException('The "id" configuration is required.');
 		}
 
-		$this->registerDefaultAliases();
+		if (isset($config['basePath'])) {
+			$this->setBasePath($config['basePath']);
+			unset($config['basePath']);
+			Yii::$aliases['@app'] = $this->getBasePath();
+		} else {
+			throw new InvalidConfigException('The "basePath" configuration is required.');
+		}
+
+		$this->registerErrorHandlers();
 		$this->registerCoreComponents();
 
 		Component::__construct($config);
 	}
 
 	/**
-	 * Initializes the application by loading components declared in [[preload]].
-	 * If you override this method, make sure the parent implementation is invoked.
+	 * Registers error handlers.
 	 */
-	public function init()
+	public function registerErrorHandlers()
 	{
-		$this->preloadComponents();
+		if (YII_ENABLE_ERROR_HANDLER) {
+			ini_set('display_errors', 0);
+			set_exception_handler(array($this, 'handleException'));
+			set_error_handler(array($this, 'handleError'), error_reporting());
+		}
 	}
 
 	/**
@@ -165,31 +168,6 @@ class Application extends Module
 			if (ErrorException::isFatalErorr($error)) {
 				unset($this->_memoryReserve);
 				$exception = new ErrorException($error['message'], $error['type'], $error['type'], $error['file'], $error['line']);
-
-				if (function_exists('xdebug_get_function_stack')) {
-					$trace = array_slice(array_reverse(xdebug_get_function_stack()), 4, -1);
-					foreach ($trace as &$frame) {
-						if (!isset($frame['function'])) {
-							$frame['function'] = 'unknown';
-						}
-
-						// XDebug < 2.1.1: http://bugs.xdebug.org/view.php?id=695
-						if (!isset($frame['type'])) {
-							$frame['type'] = '::';
-						}
-
-						// XDebug has a different key name
-						$frame['args'] = array();
-						if (isset($frame['params']) && !isset($frame['args'])) {
-							$frame['args'] = $frame['params'];
-						}
-					}
-
-					$ref = new \ReflectionProperty('Exception', 'trace');
-					$ref->setAccessible(true);
-					$ref->setValue($exception, $trace);
-				}
-
 				$this->logException($exception);
 
 				if (($handler = $this->getErrorHandler()) !== null) {
@@ -295,37 +273,6 @@ class Application extends Module
 		date_default_timezone_set($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 database connection component.
 	 * @return \yii\db\Connection the database connection
@@ -390,14 +337,6 @@ class Application extends Module
 	}
 
 	/**
-	 * Sets default path aliases.
-	 */
-	public function registerDefaultAliases()
-	{
-		Yii::$aliases['@app'] = $this->getBasePath();
-	}
-
-	/**
 	 * Registers the core application components.
 	 * @see setComponents
 	 */
diff --git a/framework/base/Component.php b/framework/base/Component.php
index f1d549b..80259e7 100644
--- a/framework/base/Component.php
+++ b/framework/base/Component.php
@@ -7,26 +7,23 @@
 
 namespace yii\base;
 
+use Yii;
+
 /**
- * Component is the base class that provides the *property*, *event* and *behavior* features.
- *
  * @include @yii/base/Component.md
- *
- * @property Behavior[] behaviors list of behaviors currently attached to this component
- *
  * @author Qiang Xue <qiang.xue@gmail.com>
  * @since 2.0
  */
-class Component extends \yii\base\Object
+class Component extends Object
 {
 	/**
-	 * @var Vector[] the attached event handlers (event name => handlers)
+	 * @var array the attached event handlers (event name => handlers)
 	 */
-	private $_e;
+	private $_events;
 	/**
 	 * @var Behavior[] the attached behaviors (behavior name => behavior)
 	 */
-	private $_b;
+	private $_behaviors;
 
 	/**
 	 * Returns the value of a component property.
@@ -52,7 +49,7 @@ class Component extends \yii\base\Object
 		} else {
 			// behavior property
 			$this->ensureBehaviors();
-			foreach ($this->_b as $behavior) {
+			foreach ($this->_behaviors as $behavior) {
 				if ($behavior->canGetProperty($name)) {
 					return $behavior->$name;
 				}
@@ -87,17 +84,16 @@ class Component extends \yii\base\Object
 			return;
 		} elseif (strncmp($name, 'on ', 3) === 0) {
 			// on event: attach event handler
-			$name = trim(substr($name, 3));
-			$this->getEventHandlers($name)->add($value);
+			$this->on(trim(substr($name, 3)), $value);
 			return;
 		} elseif (strncmp($name, 'as ', 3) === 0) {
 			// as behavior: attach behavior
 			$name = trim(substr($name, 3));
-			$this->attachBehavior($name, $value instanceof Behavior ? $value : \Yii::createObject($value));
+			$this->attachBehavior($name, $value instanceof Behavior ? $value : Yii::createObject($value));
 		} else {
 			// behavior property
 			$this->ensureBehaviors();
-			foreach ($this->_b as $behavior) {
+			foreach ($this->_behaviors as $behavior) {
 				if ($behavior->canSetProperty($name)) {
 					$behavior->$name = $value;
 					return;
@@ -131,7 +127,7 @@ class Component extends \yii\base\Object
 		} else {
 			// behavior property
 			$this->ensureBehaviors();
-			foreach ($this->_b as $behavior) {
+			foreach ($this->_behaviors as $behavior) {
 				if ($behavior->canGetProperty($name)) {
 					return $behavior->$name !== null;
 				}
@@ -161,7 +157,7 @@ class Component extends \yii\base\Object
 		} else {
 			// behavior property
 			$this->ensureBehaviors();
-			foreach ($this->_b as $behavior) {
+			foreach ($this->_behaviors as $behavior) {
 				if ($behavior->canSetProperty($name)) {
 					$behavior->$name = null;
 					return;
@@ -198,7 +194,7 @@ class Component extends \yii\base\Object
 		}
 
 		$this->ensureBehaviors();
-		foreach ($this->_b as $object) {
+		foreach ($this->_behaviors as $object) {
 			if (method_exists($object, $name)) {
 				return call_user_func_array(array($object, $name), $params);
 			}
@@ -213,8 +209,8 @@ class Component extends \yii\base\Object
 	 */
 	public function __clone()
 	{
-		$this->_e = null;
-		$this->_b = null;
+		$this->_events = null;
+		$this->_behaviors = null;
 	}
 
 	/**
@@ -259,7 +255,7 @@ class Component extends \yii\base\Object
 			return true;
 		} else {
 			$this->ensureBehaviors();
-			foreach ($this->_b as $behavior) {
+			foreach ($this->_behaviors as $behavior) {
 				if ($behavior->canGetProperty($name, $checkVar)) {
 					return true;
 				}
@@ -289,7 +285,7 @@ class Component extends \yii\base\Object
 			return true;
 		} else {
 			$this->ensureBehaviors();
-			foreach ($this->_b as $behavior) {
+			foreach ($this->_behaviors as $behavior) {
 				if ($behavior->canSetProperty($name, $checkVar)) {
 					return true;
 				}
@@ -337,44 +333,17 @@ class Component extends \yii\base\Object
 	public function hasEventHandlers($name)
 	{
 		$this->ensureBehaviors();
-		return isset($this->_e[$name]) && $this->_e[$name]->getCount();
-	}
-
-	/**
-	 * Returns the list of attached event handlers for an event.
-	 * You may manipulate the returned [[Vector]] object by adding or removing handlers.
-	 * For example,
-	 *
-	 * ~~~
-	 * $component->getEventHandlers($eventName)->insertAt(0, $eventHandler);
-	 * ~~~
-	 *
-	 * @param string $name the event name
-	 * @return Vector list of attached event handlers for the event
-	 */
-	public function getEventHandlers($name)
-	{
-		if (!isset($this->_e[$name])) {
-			$this->_e[$name] = new Vector;
-		}
-		$this->ensureBehaviors();
-		return $this->_e[$name];
+		return !empty($this->_events[$name]);
 	}
 
 	/**
 	 * Attaches an event handler to an event.
 	 *
-	 * This is equivalent to the following code:
-	 *
-	 * ~~~
-	 * $component->getEventHandlers($eventName)->add($eventHandler);
-	 * ~~~
-	 *
 	 * An event handler must be a valid PHP callback. The followings are
 	 * some examples:
 	 *
 	 * ~~~
-	 * function($event) { ... }         // anonymous function
+	 * function ($event) { ... }         // anonymous function
 	 * array($object, 'handleClick')    // $object->handleClick()
 	 * array('Page', 'handleClick')     // Page::handleClick()
 	 * 'handleClick'                    // global function handleClick()
@@ -383,31 +352,53 @@ class Component extends \yii\base\Object
 	 * An event handler must be defined with the following signature,
 	 *
 	 * ~~~
-	 * function handlerName($event) {}
+	 * function ($event)
 	 * ~~~
 	 *
 	 * where `$event` is an [[Event]] object which includes parameters associated with the event.
 	 *
 	 * @param string $name the event name
-	 * @param string|array|\Closure $handler the event handler
+	 * @param callback $handler the event handler
+	 * @param mixed $data the data to be passed to the event handler when the event is triggered.
+	 * When the event handler is invoked, this data can be accessed via [[Event::data]].
 	 * @see off()
 	 */
-	public function on($name, $handler)
+	public function on($name, $handler, $data = null)
 	{
-		$this->getEventHandlers($name)->add($handler);
+		$this->ensureBehaviors();
+		$this->_events[$name][] = array($handler, $data);
 	}
 
 	/**
 	 * Detaches an existing event handler from this component.
 	 * This method is the opposite of [[on()]].
 	 * @param string $name event name
-	 * @param string|array|\Closure $handler the event handler to be removed
+	 * @param callback $handler the event handler to be removed.
+	 * If it is null, all handlers attached to the named event will be removed.
 	 * @return boolean if a handler is found and detached
 	 * @see on()
 	 */
-	public function off($name, $handler)
+	public function off($name, $handler = null)
 	{
-		return $this->getEventHandlers($name)->remove($handler) !== false;
+		$this->ensureBehaviors();
+		if (isset($this->_events[$name])) {
+			if ($handler === null) {
+				$this->_events[$name] = array();
+			} else {
+				$removed = false;
+				foreach ($this->_events[$name] as $i => $event) {
+					if ($event[0] === $handler) {
+						unset($this->_events[$name][$i]);
+						$removed = true;
+					}
+				}
+				if ($removed) {
+					$this->_events[$name] = array_values($this->_events[$name]);
+				}
+				return $removed;
+			}
+		}
+		return false;
 	}
 
 	/**
@@ -420,7 +411,7 @@ class Component extends \yii\base\Object
 	public function trigger($name, $event = null)
 	{
 		$this->ensureBehaviors();
-		if (isset($this->_e[$name]) && $this->_e[$name]->getCount()) {
+		if (!empty($this->_events[$name])) {
 			if ($event === null) {
 				$event = new Event;
 			}
@@ -429,8 +420,9 @@ class Component extends \yii\base\Object
 			}
 			$event->handled = false;
 			$event->name = $name;
-			foreach ($this->_e[$name] as $handler) {
-				call_user_func($handler, $event);
+			foreach ($this->_events[$name] as $handler) {
+				$event->data = $handler[1];
+				call_user_func($handler[0], $event);
 				// stop further handling if the event is handled
 				if ($event instanceof Event && $event->handled) {
 					return;
@@ -447,7 +439,7 @@ class Component extends \yii\base\Object
 	public function getBehavior($name)
 	{
 		$this->ensureBehaviors();
-		return isset($this->_b[$name]) ? $this->_b[$name] : null;
+		return isset($this->_behaviors[$name]) ? $this->_behaviors[$name] : null;
 	}
 
 	/**
@@ -457,20 +449,20 @@ class Component extends \yii\base\Object
 	public function getBehaviors()
 	{
 		$this->ensureBehaviors();
-		return $this->_b;
+		return $this->_behaviors;
 	}
 
 	/**
 	 * Attaches a behavior to this component.
 	 * This method will create the behavior object based on the given
 	 * configuration. After that, the behavior object will be attached to
-	 * this component by calling the [[Behavior::attach]] method.
+	 * this component by calling the [[Behavior::attach()]] method.
 	 * @param string $name the name of the behavior.
 	 * @param string|array|Behavior $behavior the behavior configuration. This can be one of the following:
 	 *
 	 *  - a [[Behavior]] object
 	 *  - a string specifying the behavior class
-	 *  - an object configuration array that will be passed to [[\Yii::createObject()]] to create the behavior object.
+	 *  - an object configuration array that will be passed to [[Yii::createObject()]] to create the behavior object.
 	 *
 	 * @return Behavior the behavior object
 	 * @see detachBehavior
@@ -498,15 +490,15 @@ class Component extends \yii\base\Object
 
 	/**
 	 * Detaches a behavior from the component.
-	 * The behavior's [[Behavior::detach]] method will be invoked.
+	 * The behavior's [[Behavior::detach()]] method will be invoked.
 	 * @param string $name the behavior's name.
 	 * @return Behavior the detached behavior. Null if the behavior does not exist.
 	 */
 	public function detachBehavior($name)
 	{
-		if (isset($this->_b[$name])) {
-			$behavior = $this->_b[$name];
-			unset($this->_b[$name]);
+		if (isset($this->_behaviors[$name])) {
+			$behavior = $this->_behaviors[$name];
+			unset($this->_behaviors[$name]);
 			$behavior->detach();
 			return $behavior;
 		} else {
@@ -519,12 +511,12 @@ class Component extends \yii\base\Object
 	 */
 	public function detachBehaviors()
 	{
-		if ($this->_b !== null) {
-			foreach ($this->_b as $name => $behavior) {
+		if ($this->_behaviors !== null) {
+			foreach ($this->_behaviors as $name => $behavior) {
 				$this->detachBehavior($name);
 			}
 		}
-		$this->_b = array();
+		$this->_behaviors = array();
 	}
 
 	/**
@@ -532,8 +524,8 @@ class Component extends \yii\base\Object
 	 */
 	public function ensureBehaviors()
 	{
-		if ($this->_b === null) {
-			$this->_b = array();
+		if ($this->_behaviors === null) {
+			$this->_behaviors = array();
 			foreach ($this->behaviors() as $name => $behavior) {
 				$this->attachBehaviorInternal($name, $behavior);
 			}
@@ -549,12 +541,12 @@ class Component extends \yii\base\Object
 	private function attachBehaviorInternal($name, $behavior)
 	{
 		if (!($behavior instanceof Behavior)) {
-			$behavior = \Yii::createObject($behavior);
+			$behavior = Yii::createObject($behavior);
 		}
-		if (isset($this->_b[$name])) {
-			$this->_b[$name]->detach();
+		if (isset($this->_behaviors[$name])) {
+			$this->_behaviors[$name]->detach();
 		}
 		$behavior->attach($this);
-		return $this->_b[$name] = $behavior;
+		return $this->_behaviors[$name] = $behavior;
 	}
 }
diff --git a/framework/base/Controller.php b/framework/base/Controller.php
index 241c66c..6ff68da 100644
--- a/framework/base/Controller.php
+++ b/framework/base/Controller.php
@@ -357,7 +357,8 @@ class Controller extends Component
 	 */
 	public function renderPartial($view, $params = array())
 	{
-		return $this->getView()->render($view, $params, $this);
+		$viewFile = $this->findViewFile($view);
+		return $this->getView()->renderFile($viewFile, $params, $this);
 	}
 
 	/**
diff --git a/framework/base/ErrorException.php b/framework/base/ErrorException.php
index 465d839..93390e7 100644
--- a/framework/base/ErrorException.php
+++ b/framework/base/ErrorException.php
@@ -7,6 +7,8 @@
 
 namespace yii\base;
 
+use Yii;
+
 /**
  * ErrorException represents a PHP error.
  *
@@ -33,6 +35,32 @@ class ErrorException extends Exception
 		$this->severity = $severity;
 		$this->file = $filename;
 		$this->line = $lineno;
+
+		if (function_exists('xdebug_get_function_stack')) {
+			$trace = array_slice(array_reverse(xdebug_get_function_stack()), 3, -1);
+			foreach ($trace as &$frame) {
+				if (!isset($frame['function'])) {
+					$frame['function'] = 'unknown';
+				}
+
+				// XDebug < 2.1.1: http://bugs.xdebug.org/view.php?id=695
+				if (!isset($frame['type']) || $frame['type'] === 'static') {
+					$frame['type'] = '::';
+				} elseif ($frame['type'] === 'dynamic') {
+					$frame['type'] = '->';
+				}
+
+				// XDebug has a different key name
+				$frame['args'] = array();
+				if (isset($frame['params']) && !isset($frame['args'])) {
+					$frame['args'] = $frame['params'];
+				}
+			}
+
+			$ref = new \ReflectionProperty('Exception', 'trace');
+			$ref->setAccessible(true);
+			$ref->setValue($this, $trace);
+		}
 	}
 
 	/**
@@ -62,20 +90,20 @@ class ErrorException extends Exception
 	public function getName()
 	{
 		$names = array(
-			E_ERROR => \Yii::t('yii|Fatal Error'),
-			E_PARSE => \Yii::t('yii|Parse Error'),
-			E_CORE_ERROR => \Yii::t('yii|Core Error'),
-			E_COMPILE_ERROR => \Yii::t('yii|Compile Error'),
-			E_USER_ERROR => \Yii::t('yii|User Error'),
-			E_WARNING => \Yii::t('yii|Warning'),
-			E_CORE_WARNING => \Yii::t('yii|Core Warning'),
-			E_COMPILE_WARNING => \Yii::t('yii|Compile Warning'),
-			E_USER_WARNING => \Yii::t('yii|User Warning'),
-			E_STRICT => \Yii::t('yii|Strict'),
-			E_NOTICE => \Yii::t('yii|Notice'),
-			E_RECOVERABLE_ERROR => \Yii::t('yii|Recoverable Error'),
-			E_DEPRECATED => \Yii::t('yii|Deprecated'),
+			E_ERROR => Yii::t('yii|Fatal Error'),
+			E_PARSE => Yii::t('yii|Parse Error'),
+			E_CORE_ERROR => Yii::t('yii|Core Error'),
+			E_COMPILE_ERROR => Yii::t('yii|Compile Error'),
+			E_USER_ERROR => Yii::t('yii|User Error'),
+			E_WARNING => Yii::t('yii|Warning'),
+			E_CORE_WARNING => Yii::t('yii|Core Warning'),
+			E_COMPILE_WARNING => Yii::t('yii|Compile Warning'),
+			E_USER_WARNING => Yii::t('yii|User Warning'),
+			E_STRICT => Yii::t('yii|Strict'),
+			E_NOTICE => Yii::t('yii|Notice'),
+			E_RECOVERABLE_ERROR => Yii::t('yii|Recoverable Error'),
+			E_DEPRECATED => Yii::t('yii|Deprecated'),
 		);
-		return isset($names[$this->getCode()]) ? $names[$this->getCode()] : \Yii::t('yii|Error');
+		return isset($names[$this->getCode()]) ? $names[$this->getCode()] : Yii::t('yii|Error');
 	}
 }
diff --git a/framework/base/Event.php b/framework/base/Event.php
index b86ed7c..5d40736 100644
--- a/framework/base/Event.php
+++ b/framework/base/Event.php
@@ -15,12 +15,14 @@ namespace yii\base;
  * And the [[handled]] property indicates if the event is handled.
  * If an event handler sets [[handled]] to be true, the rest of the
  * uninvoked handlers will no longer be called to handle the event.
- * Additionally, an event may specify extra parameters via the [[data]] property.
+ *
+ * Additionally, when attaching an event handler, extra data may be passed
+ * and be available via the [[data]] property when the event handler is invoked.
  *
  * @author Qiang Xue <qiang.xue@gmail.com>
  * @since 2.0
  */
-class Event extends \yii\base\Object
+class Event extends Object
 {
 	/**
 	 * @var string the event name. This property is set by [[Component::trigger()]].
@@ -39,7 +41,8 @@ class Event extends \yii\base\Object
 	 */
 	public $handled = false;
 	/**
-	 * @var mixed extra custom data associated with the event.
+	 * @var mixed the data that is passed to [[Component::on()]] when attaching an event handler.
+	 * Note that this varies according to which event handler is currently executing.
 	 */
 	public $data;
 }
diff --git a/framework/base/Model.php b/framework/base/Model.php
index 611b12e..7f55239 100644
--- a/framework/base/Model.php
+++ b/framework/base/Model.php
@@ -8,8 +8,8 @@
 namespace yii\base;
 
 use yii\helpers\StringHelper;
-use yii\validators\Validator;
 use yii\validators\RequiredValidator;
+use yii\validators\Validator;
 
 /**
  * Model is the base class for data models.
@@ -169,6 +169,26 @@ class Model extends Component implements \IteratorAggregate, \ArrayAccess
 	}
 
 	/**
+	 * Returns the form name that this model class should use.
+	 *
+	 * The form name is mainly used by [[\yii\web\ActiveForm]] to determine how to name
+	 * the input fields for the attributes in a model. If the form name is "A" and an attribute
+	 * name is "b", then the corresponding input name would be "A[b]". If the form name is
+	 * an empty string, then the input name would be "b".
+	 *
+	 * By default, this method returns the model class name (without the namespace part)
+	 * as the form name. You may override it when the model is used in different forms.
+	 *
+	 * @return string the form name of this model class.
+	 */
+	public function formName()
+	{
+		$class = get_class($this);
+		$pos = strrpos($class, '\\');
+		return $pos === false ? $class : substr($class, $pos + 1);
+	}
+
+	/**
 	 * Returns the list of attribute names.
 	 * By default, this method returns all public non-static properties of the class.
 	 * You may override this method to change the default behavior.
diff --git a/framework/base/Module.php b/framework/base/Module.php
index 3e7eb04..2ccf61d 100644
--- a/framework/base/Module.php
+++ b/framework/base/Module.php
@@ -170,7 +170,6 @@ abstract class Module extends Component
 	 */
 	public function init()
 	{
-		Yii::setAlias('@' . $this->id, $this->getBasePath());
 		$this->preloadComponents();
 	}
 
@@ -580,8 +579,9 @@ abstract class Module extends Component
 	 * instance of it.
 	 *
 	 * @param string $route the route consisting of module, controller and action IDs.
-	 * @return array|boolean if the controller is created successfully, it will be returned together
-	 * with the remainder of the route which represents the action ID. Otherwise false will be returned.
+	 * @return array|boolean If the controller is created successfully, it will be returned together
+	 * with the requested action ID. Otherwise false will be returned.
+	 * @throws InvalidConfigException if the controller class and its file do not match.
 	 */
 	public function createController($route)
 	{
@@ -605,21 +605,14 @@ abstract class Module extends Component
 			$controller = Yii::createObject($this->controllerMap[$id], $id, $this);
 		} elseif (preg_match('/^[a-z0-9\\-_]+$/', $id)) {
 			$className = StringHelper::id2camel($id) . 'Controller';
-
 			$classFile = $this->controllerPath . DIRECTORY_SEPARATOR . $className . '.php';
-			if (is_file($classFile)) {
-				$className = $this->controllerNamespace . '\\' . $className;
-				if (!class_exists($className, false)) {
-					require($classFile);
-				}
-				if (class_exists($className, false) && is_subclass_of($className, '\yii\base\Controller')) {
+			$className = ltrim($this->controllerNamespace . '\\' . $className, '\\');
+			Yii::$classMap[$className] = $classFile;
+			if (class_exists($className)) {
+				if (is_subclass_of($className, 'yii\base\Controller')) {
 					$controller = new $className($id, $this);
-				} elseif (YII_DEBUG) {
-					if (!class_exists($className, false)) {
-						throw new InvalidConfigException("Class file name does not match class name: $className.");
-					} elseif (!is_subclass_of($className, '\yii\base\Controller')) {
-						throw new InvalidConfigException("Controller class must extend from \\yii\\base\\Controller.");
-					}
+				} elseif (YII_DEBUG && !is_subclass_of($className, 'yii\base\Controller')) {
+					throw new InvalidConfigException("Controller class must extend from \\yii\\base\\Controller.");
 				}
 			}
 		}
diff --git a/framework/base/Object.php b/framework/base/Object.php
index 3bd8378..a547990 100644
--- a/framework/base/Object.php
+++ b/framework/base/Object.php
@@ -8,10 +8,7 @@
 namespace yii\base;
 
 /**
- * Object is the base class that provides the *property* feature.
- *
  * @include @yii/base/Object.md
- *
  * @author Qiang Xue <qiang.xue@gmail.com>
  * @since 2.0
  */
diff --git a/framework/base/Theme.php b/framework/base/Theme.php
index 88ecb0a..e529a63 100644
--- a/framework/base/Theme.php
+++ b/framework/base/Theme.php
@@ -33,11 +33,17 @@ use yii\helpers\FileHelper;
 class Theme extends Component
 {
 	/**
-	 * @var string the root path of this theme.
+	 * @var string the root path or path alias of this theme. All resources of this theme are located
+	 * under this directory. This property must be set if [[pathMap]] is not set.
 	 * @see pathMap
 	 */
 	public $basePath;
 	/**
+	 * @var string the base URL (or path alias) for this theme. All resources of this theme are considered
+	 * to be under this base URL. This property must be set. It is mainly used by [[getUrl()]].
+	 */
+	public $baseUrl;
+	/**
 	 * @var array the mapping between view directories and their corresponding themed versions.
 	 * If not set, it will be initialized as a mapping from [[Application::basePath]] to [[basePath]].
 	 * This property is used by [[applyTo()]] when a view is trying to apply the theme.
@@ -45,7 +51,6 @@ class Theme extends Component
 	 */
 	public $pathMap;
 
-	private $_baseUrl;
 
 	/**
 	 * Initializes the theme.
@@ -69,25 +74,11 @@ class Theme extends Component
 			$paths[$from . DIRECTORY_SEPARATOR] = $to . DIRECTORY_SEPARATOR;
 		}
 		$this->pathMap = $paths;
-	}
-
-	/**
-	 * Returns the base URL for this theme.
-	 * The method [[getUrl()]] will prefix this to the given URL.
-	 * @return string the base URL for this theme.
-	 */
-	public function getBaseUrl()
-	{
-		return $this->_baseUrl;
-	}
-
-	/**
-	 * Sets the base URL for this theme.
-	 * @param string $value the base URL for this theme.
-	 */
-	public function setBaseUrl($value)
-	{
-		$this->_baseUrl = rtrim(Yii::getAlias($value), '/');
+		if ($this->baseUrl === null) {
+			throw new InvalidConfigException("Theme::baseUrl must be set.");
+		} else {
+			$this->baseUrl = rtrim(Yii::getAlias($this->baseUrl), '/');
+		}
 	}
 
 	/**
@@ -112,7 +103,7 @@ class Theme extends Component
 	}
 
 	/**
-	 * Converts a relative URL into an absolute URL using [[basePath]].
+	 * Converts a relative URL into an absolute URL using [[baseUrl]].
 	 * @param string $url the relative URL to be converted.
 	 * @return string the absolute URL
 	 */
diff --git a/framework/base/View.php b/framework/base/View.php
index d3d9339..8b1f4ef 100644
--- a/framework/base/View.php
+++ b/framework/base/View.php
@@ -22,10 +22,23 @@ use yii\helpers\FileHelper;
 class View extends Component
 {
 	/**
+	 * @event Event an event that is triggered by [[renderFile()]] right before it renders a view file.
+	 */
+	const EVENT_BEFORE_RENDER = 'beforeRender';
+	/**
+	 * @event Event an event that is triggered by [[renderFile()]] right after it renders a view file.
+	 */
+	const EVENT_AFTER_RENDER = 'afterRender';
+
+	/**
 	 * @var object the object that owns this view. This can be a controller, a widget, or any other object.
 	 */
 	public $context;
 	/**
+	 * @var ViewContent
+	 */
+	public $content;
+	/**
 	 * @var mixed custom parameters that are shared among view templates.
 	 */
 	public $params;
@@ -47,7 +60,7 @@ class View extends Component
 	public $clips;
 	/**
 	 * @var Widget[] the widgets that are currently being rendered (not ended). This property
-	 * is maintained by [[beginWidget()]] and [[endWidget()]] methods. Do not modify it directly.
+	 * is maintained by [[beginWidget()]] and [[endWidget()]] methods. Do not modify it.
 	 */
 	public $widgetStack = array();
 	/**
@@ -74,6 +87,11 @@ class View extends Component
 		if (is_array($this->theme)) {
 			$this->theme = Yii::createObject($this->theme);
 		}
+		if (is_array($this->content)) {
+			$this->content = Yii::createObject($this->content);
+		} else {
+			$this->content = new ViewContent;
+		}
 	}
 
 	/**
@@ -140,10 +158,15 @@ class View extends Component
 			$this->context = $context;
 		}
 
-		if ($this->renderer !== null) {
-			$output = $this->renderer->render($this, $viewFile, $params);
-		} else {
-			$output = $this->renderPhpFile($viewFile, $params);
+		$output = '';
+		if ($this->beforeRender($viewFile)) {
+			if ($this->renderer !== null) {
+				$output = $this->renderer->render($this, $viewFile, $params);
+			} else {
+				$output = $this->renderPhpFile($viewFile, $params);
+			}
+			$output = $this->content->populate($output);
+			$this->afterRender($viewFile, $output);
 		}
 
 		$this->context = $oldContext;
@@ -152,6 +175,38 @@ class View extends Component
 	}
 
 	/**
+	 * This method is invoked right before [[renderFile()]] renders a view file.
+	 * The default implementation will trigger the [[EVENT_BEFORE_RENDER]] event.
+	 * If you override this method, make sure you call the parent implementation first.
+	 * @param string $viewFile the view file to be rendered
+	 * @return boolean whether to continue rendering the view file.
+	 */
+	public function beforeRender($viewFile)
+	{
+		$event = new ViewEvent($viewFile);
+		$this->trigger(self::EVENT_BEFORE_RENDER, $event);
+		return $event->isValid;
+	}
+
+	/**
+	 * This method is invoked right after [[renderFile()]] renders a view file.
+	 * The default implementation will trigger the [[EVENT_AFTER_RENDER]] event.
+	 * If you override this method, make sure you call the parent implementation first.
+	 * @param string $viewFile the view file to be rendered
+	 * @param string $output the rendering result of the view file. Updates to this parameter
+	 * will be passed back and returned by [[renderFile()]].
+	 */
+	public function afterRender($viewFile, &$output)
+	{
+		if ($this->hasEventHandlers(self::EVENT_AFTER_RENDER)) {
+			$event = new ViewEvent($viewFile);
+			$event->output = $output;
+			$this->trigger(self::EVENT_AFTER_RENDER, $event);
+			$output = $event->output;
+		}
+	}
+
+	/**
 	 * Renders a view file as a PHP script.
 	 *
 	 * This method treats the view file as a PHP script and includes the file.
diff --git a/framework/base/ViewContent.php b/framework/base/ViewContent.php
new file mode 100644
index 0000000..6a3b489
--- /dev/null
+++ b/framework/base/ViewContent.php
@@ -0,0 +1,136 @@
+<?php
+/**
+ * @link http://www.yiiframework.com/
+ * @copyright Copyright (c) 2008 Yii Software LLC
+ * @license http://www.yiiframework.com/license/
+ */
+
+namespace yii\base;
+
+/**
+ * @author Qiang Xue <qiang.xue@gmail.com>
+ * @since 2.0
+ */
+class ViewContent extends Component
+{
+	const POS_HEAD = 1;
+	const POS_BEGIN = 2;
+	const POS_END = 3;
+
+	/**
+	 * @var array
+	 *
+	 * Each asset bundle should be declared with the following structure:
+	 *
+	 * ~~~
+	 * array(
+	 *     'basePath' => '...',
+	 *     'baseUrl' => '...',  // if missing, the bundle will be published to the "www/assets" folder
+	 *     'js' => array(
+	 *         'js/main.js',
+	 *         'js/menu.js',
+	 *         'js/base.js' => self::POS_HEAD,
+	 *     'css' => array(
+	 *         'css/main.css',
+	 *         'css/menu.css',
+	 *     ),
+	 *     'depends' => array(
+	 *         'jquery',
+	 *         'yii',
+	 *         'yii/treeview',
+	 *     ),
+	 * )
+	 * ~~~
+	 */
+	public $bundles;
+
+	public $title;
+	public $metaTags;
+	public $linkTags;
+	public $css;
+	public $js;
+	public $cssFiles;
+	public $jsFiles;
+
+	public function populate($content)
+	{
+		return $content;
+	}
+
+	public function reset()
+	{
+		$this->title = null;
+		$this->metaTags = null;
+		$this->linkTags = null;
+		$this->css = null;
+		$this->js = null;
+		$this->cssFiles = null;
+		$this->jsFiles = null;
+	}
+
+	public function registerBundle($name)
+	{
+
+	}
+
+	public function getMetaTag($key)
+	{
+		return isset($this->metaTags[$key]) ? $this->metaTags[$key] : null;
+	}
+
+	public function setMetaTag($key, $tag)
+	{
+		$this->metaTags[$key] = $tag;
+	}
+
+	public function getLinkTag($key)
+	{
+		return isset($this->linkTags[$key]) ? $this->linkTags[$key] : null;
+	}
+
+	public function setLinkTag($key, $tag)
+	{
+		$this->linkTags[$key] = $tag;
+	}
+
+	public function getCss($key)
+	{
+		return isset($this->css[$key]) ? $this->css[$key]: null;
+	}
+
+	public function setCss($key, $css)
+	{
+		$this->css[$key] = $css;
+	}
+
+	public function getCssFile($key)
+	{
+		return isset($this->cssFiles[$key]) ? $this->cssFiles[$key]: null;
+	}
+
+	public function setCssFile($key, $file)
+	{
+		$this->cssFiles[$key] = $file;
+	}
+
+	public function getJs($key, $position = self::POS_END)
+	{
+		return isset($this->js[$position][$key]) ? $this->js[$position][$key] : null;
+	}
+
+	public function setJs($key, $js, $position = self::POS_END)
+	{
+		$this->js[$position][$key] = $js;
+	}
+
+	public function getJsFile($key, $position = self::POS_END)
+	{
+		return isset($this->jsFiles[$position][$key]) ? $this->jsFiles[$position][$key] : null;
+	}
+
+	public function setJsFile($key, $file, $position = self::POS_END)
+	{
+		$this->jsFiles[$position][$key] = $file;
+	}
+
+}
\ No newline at end of file
diff --git a/framework/base/ViewEvent.php b/framework/base/ViewEvent.php
new file mode 100644
index 0000000..cac7be4
--- /dev/null
+++ b/framework/base/ViewEvent.php
@@ -0,0 +1,44 @@
+<?php
+/**
+ * @link http://www.yiiframework.com/
+ * @copyright Copyright (c) 2008 Yii Software LLC
+ * @license http://www.yiiframework.com/license/
+ */
+
+namespace yii\base;
+
+/**
+ * @author Qiang Xue <qiang.xue@gmail.com>
+ * @since 2.0
+ */
+class ViewEvent extends Event
+{
+	/**
+	 * @var string the rendering result of [[View::renderFile()]].
+	 * Event handlers may modify this property and the modified output will be
+	 * returned by [[View::renderFile()]]. This property is only used
+	 * by [[View::EVENT_AFTER_RENDER]] event.
+	 */
+	public $output;
+	/**
+	 * @var string the view file path that is being rendered by [[View::renderFile()]].
+	 */
+	public $viewFile;
+	/**
+	 * @var boolean whether to continue rendering the view file. Event handlers of
+	 * [[View::EVENT_BEFORE_RENDER]] may set this property to decide whether
+	 * to continue rendering the current view file.
+	 */
+	public $isValid = true;
+
+	/**
+	 * Constructor.
+	 * @param string $viewFile the view file path that is being rendered by [[View::renderFile()]].
+	 * @param array $config name-value pairs that will be used to initialize the object properties
+	 */
+	public function __construct($viewFile, $config = array())
+	{
+		$this->viewFile = $viewFile;
+		parent::__construct($config);
+	}
+}
\ No newline at end of file
diff --git a/framework/caching/ChainedDependency.php b/framework/caching/ChainedDependency.php
index af34e9d..7c7058e 100644
--- a/framework/caching/ChainedDependency.php
+++ b/framework/caching/ChainedDependency.php
@@ -22,11 +22,10 @@ namespace yii\caching;
 class ChainedDependency extends Dependency
 {
 	/**
-	 * @var array list of dependencies that this dependency is composed of.
-	 * Each array element should be a dependency object or a configuration array
-	 * that can be used to create a dependency object via [[\Yii::createObject()]].
+	 * @var Dependency[] list of dependencies that this dependency is composed of.
+	 * Each array element must be a dependency object.
 	 */
-	public $dependencies = array();
+	public $dependencies;
 	/**
 	 * @var boolean whether this dependency is depending on every dependency in [[dependencies]].
 	 * Defaults to true, meaning if any of the dependencies has changed, this dependency is considered changed.
@@ -37,9 +36,8 @@ class ChainedDependency extends Dependency
 
 	/**
 	 * Constructor.
-	 * @param array $dependencies list of dependencies that this dependency is composed of.
-	 * Each array element should be a dependency object or a configuration array
-	 * that can be used to create a dependency object via [[\Yii::createObject()]].
+	 * @param Dependency[] $dependencies list of dependencies that this dependency is composed of.
+	 * Each array element should be a dependency object.
 	 * @param array $config name-value pairs that will be used to initialize the object properties
 	 */
 	public function __construct($dependencies = array(), $config = array())
@@ -54,9 +52,6 @@ class ChainedDependency extends Dependency
 	public function evaluateDependency()
 	{
 		foreach ($this->dependencies as $dependency) {
-			if (!$dependency instanceof Dependency) {
-				$dependency = \Yii::createObject($dependency);
-			}
 			$dependency->evaluateDependency();
 		}
 	}
@@ -79,10 +74,7 @@ class ChainedDependency extends Dependency
 	 */
 	public function getHasChanged()
 	{
-		foreach ($this->dependencies as $i => $dependency) {
-			if (!$dependency instanceof Dependency) {
-				$this->dependencies[$i] = $dependency = \Yii::createObject($dependency);
-			}
+		foreach ($this->dependencies as $dependency) {
 			if ($this->dependOnAll && $dependency->getHasChanged()) {
 				return true;
 			} elseif (!$this->dependOnAll && !$dependency->getHasChanged()) {
diff --git a/framework/caching/DbDependency.php b/framework/caching/DbDependency.php
index 4308dc1..cbe0ae1 100644
--- a/framework/caching/DbDependency.php
+++ b/framework/caching/DbDependency.php
@@ -28,23 +28,25 @@ class DbDependency extends Dependency
 	public $db = 'db';
 	/**
 	 * @var string the SQL query whose result is used to determine if the dependency has been changed.
-	 * Only the first row of the query result will be used. This property must be always set, otherwise
-	 * an exception would be raised.
+	 * Only the first row of the query result will be used.
 	 */
 	public $sql;
 	/**
 	 * @var array the parameters (name=>value) to be bound to the SQL statement specified by [[sql]].
 	 */
-	public $params = array();
+	public $params;
 
 	/**
-	 * Initializes the database dependency object.
+	 * Constructor.
+	 * @param string $sql the SQL query whose result is used to determine if the dependency has been changed.
+	 * @param array $params the parameters (name=>value) to be bound to the SQL statement specified by [[sql]].
+	 * @param array $config name-value pairs that will be used to initialize the object properties
 	 */
-	public function init()
+	public function __construct($sql, $params = array(), $config = array())
 	{
-		if ($this->sql === null) {
-			throw new InvalidConfigException('DbDependency::sql must be set.');
-		}
+		$this->sql = $sql;
+		$this->params = $params;
+		parent::__construct($config);
 	}
 
 	/**
diff --git a/framework/caching/ExpressionDependency.php b/framework/caching/ExpressionDependency.php
index bf70291..e13c962 100644
--- a/framework/caching/ExpressionDependency.php
+++ b/framework/caching/ExpressionDependency.php
@@ -22,7 +22,18 @@ class ExpressionDependency extends Dependency
 	/**
 	 * @var string the PHP expression whose result is used to determine the dependency.
 	 */
-	public $expression = 'true';
+	public $expression;
+
+	/**
+	 * Constructor.
+	 * @param string $expression the PHP expression whose result is used to determine the dependency.
+	 * @param array $config name-value pairs that will be used to initialize the object properties
+	 */
+	public function __construct($expression = 'true', $config = array())
+	{
+		$this->expression = $expression;
+		parent::__construct($config);
+	}
 
 	/**
 	 * Generates the data needed to determine if dependency has been changed.
diff --git a/framework/caching/FileDependency.php b/framework/caching/FileDependency.php
index 8d858ec..3797dde 100644
--- a/framework/caching/FileDependency.php
+++ b/framework/caching/FileDependency.php
@@ -7,8 +7,6 @@
 
 namespace yii\caching;
 
-use yii\base\InvalidConfigException;
-
 /**
  * FileDependency represents a dependency based on a file's last modification time.
  *
@@ -22,19 +20,19 @@ class FileDependency extends Dependency
 {
 	/**
 	 * @var string the name of the file whose last modification time is used to
-	 * check if the dependency has been changed. This property must be always set,
-	 * otherwise an exception would be raised.
+	 * check if the dependency has been changed.
 	 */
 	public $fileName;
 
 	/**
-	 * Initializes the database dependency object.
+	 * Constructor.
+	 * @param string $fileName name of the file whose change is to be checked.
+	 * @param array $config name-value pairs that will be used to initialize the object properties
 	 */
-	public function init()
+	public function __construct($fileName = null, $config = array())
 	{
-		if ($this->file === null) {
-			throw new InvalidConfigException('FileDependency::fileName must be set.');
-		}
+		$this->fileName = $fileName;
+		parent::__construct($config);
 	}
 
 	/**
diff --git a/framework/logging/FileTarget.php b/framework/logging/FileTarget.php
index c3f4031..69799cd 100644
--- a/framework/logging/FileTarget.php
+++ b/framework/logging/FileTarget.php
@@ -6,6 +6,8 @@
  */
 
 namespace yii\logging;
+
+use Yii;
 use yii\base\InvalidConfigException;
 
 /**
@@ -23,15 +25,14 @@ use yii\base\InvalidConfigException;
 class FileTarget extends Target
 {
 	/**
-	 * @var string log file path or path alias. If not set, it means the 'application.log' file under
-	 * the application runtime directory. Please make sure the directory containing
-	 * the log file is writable by the Web server process.
+	 * @var string log file path or path alias. If not set, it will use the "runtime/logs/app.log" file.
+	 * The directory containing the log files will be automatically created if not existing.
 	 */
 	public $logFile;
 	/**
-	 * @var integer maximum log file size, in kilo-bytes. Defaults to 1024, meaning 1MB.
+	 * @var integer maximum log file size, in kilo-bytes. Defaults to 10240, meaning 10MB.
 	 */
-	public $maxFileSize = 1024; // in KB
+	public $maxFileSize = 10240; // in KB
 	/**
 	 * @var integer number of log files used for rotation. Defaults to 5.
 	 */
@@ -46,13 +47,13 @@ class FileTarget extends Target
 	{
 		parent::init();
 		if ($this->logFile === null) {
-			$this->logFile = \Yii::$app->getRuntimePath() . DIRECTORY_SEPARATOR . 'application.log';
+			$this->logFile = Yii::$app->getRuntimePath() . '/logs/app.log';
 		} else {
-			$this->logFile = \Yii::getAlias($this->logFile);
+			$this->logFile = Yii::getAlias($this->logFile);
 		}
 		$logPath = dirname($this->logFile);
-		if (!is_dir($logPath) || !is_writable($logPath)) {
-			throw new InvalidConfigException("Directory '$logPath' does not exist or is not writable.");
+		if (!is_dir($logPath)) {
+			@mkdir($logPath, 0777, true);
 		}
 		if ($this->maxLogFiles < 1) {
 			$this->maxLogFiles = 1;
@@ -66,6 +67,7 @@ class FileTarget extends Target
 	 * Sends log messages to specified email addresses.
 	 * @param array $messages the messages to be exported. See [[Logger::messages]] for the structure
 	 * of each message.
+	 * @throws InvalidConfigException if unable to open the log file for writing
 	 */
 	public function export($messages)
 	{
@@ -73,7 +75,9 @@ class FileTarget extends Target
 		foreach ($messages as $message) {
 			$text .= $this->formatMessage($message);
 		}
-		$fp = @fopen($this->logFile, 'a');
+		if (($fp = @fopen($this->logFile, 'a')) === false) {
+			throw new InvalidConfigException("Unable to append to log file: {$this->logFile}");
+		}
 		@flock($fp, LOCK_EX);
 		if (@filesize($this->logFile) > $this->maxFileSize * 1024) {
 			$this->rotateFiles();
diff --git a/framework/validators/BooleanValidator.php b/framework/validators/BooleanValidator.php
index 427fa44..6d2c671 100644
--- a/framework/validators/BooleanValidator.php
+++ b/framework/validators/BooleanValidator.php
@@ -7,6 +7,8 @@
 
 namespace yii\validators;
 
+use Yii;
+
 /**
  * BooleanValidator checks if the attribute value is a boolean value.
  *
@@ -32,11 +34,17 @@ class BooleanValidator extends Validator
 	 * Defaults to false, meaning only the value needs to be matched.
 	 */
 	public $strict = false;
+
 	/**
-	 * @var boolean whether the attribute value can be null or empty. Defaults to true,
-	 * meaning that if the attribute is empty, it is considered valid.
+	 * Initializes the validator.
 	 */
-	public $allowEmpty = true;
+	public function init()
+	{
+		parent::init();
+		if ($this->message === null) {
+			$this->message = Yii::t('yii|{attribute} must be either "{true}" or "{false}".');
+		}
+	}
 
 	/**
 	 * Validates the attribute of the object.
@@ -47,13 +55,8 @@ class BooleanValidator extends Validator
 	public function validateAttribute($object, $attribute)
 	{
 		$value = $object->$attribute;
-		if ($this->allowEmpty && $this->isEmpty($value)) {
-			return;
-		}
-		if (!$this->strict && $value != $this->trueValue && $value != $this->falseValue
-				|| $this->strict && $value !== $this->trueValue && $value !== $this->falseValue) {
-			$message = ($this->message !== null) ? $this->message : \Yii::t('yii|{attribute} must be either {true} or {false}.');
-			$this->addError($object, $attribute, $message, array(
+		if (!$this->validateValue($value)) {
+			$this->addError($object, $attribute, $this->message, array(
 				'{true}' => $this->trueValue,
 				'{false}' => $this->falseValue,
 			));
@@ -61,6 +64,17 @@ class BooleanValidator extends Validator
 	}
 
 	/**
+	 * Validates the given value.
+	 * @param mixed $value the value to be validated.
+	 * @return boolean whether the value is valid.
+	 */
+	public function validateValue($value)
+	{
+		return $this->strict && ($value == $this->trueValue || $value == $this->falseValue)
+			|| !$this->strict && ($value === $this->trueValue || $value === $this->falseValue);
+	}
+
+	/**
 	 * Returns the JavaScript needed for performing client-side validation.
 	 * @param \yii\base\Model $object the data object being validated
 	 * @param string $attribute the name of the attribute to be validated.
@@ -68,15 +82,14 @@ class BooleanValidator extends Validator
 	 */
 	public function clientValidateAttribute($object, $attribute)
 	{
-		$message = ($this->message !== null) ? $this->message : \Yii::t('yii|{attribute} must be either {true} or {false}.');
-		$message = strtr($message, array(
+		$message = strtr($this->message, array(
 			'{attribute}' => $object->getAttributeLabel($attribute),
 			'{value}' => $object->$attribute,
 			'{true}' => $this->trueValue,
 			'{false}' => $this->falseValue,
 		));
 		return "
-if(" . ($this->allowEmpty ? "$.trim(value)!='' && " : '') . "value!=" . json_encode($this->trueValue) . " && value!=" . json_encode($this->falseValue) . ") {
+if(" . ($this->skipOnEmpty ? "$.trim(value)!='' && " : '') . "value!=" . json_encode($this->trueValue) . " && value!=" . json_encode($this->falseValue) . ") {
 	messages.push(" . json_encode($message) . ");
 }
 ";
diff --git a/framework/validators/CaptchaValidator.php b/framework/validators/CaptchaValidator.php
index 3f31f77..3b4745b 100644
--- a/framework/validators/CaptchaValidator.php
+++ b/framework/validators/CaptchaValidator.php
@@ -7,6 +7,9 @@
 
 namespace yii\validators;
 
+use Yii;
+use yii\base\InvalidConfigException;
+
 /**
  * CaptchaValidator validates that the attribute value is the same as the verification code displayed in the CAPTCHA.
  *
@@ -22,16 +25,21 @@ class CaptchaValidator extends Validator
 	 */
 	public $caseSensitive = false;
 	/**
-	 * @var string the ID of the action that renders the CAPTCHA image. Defaults to 'captcha',
-	 * meaning the `captcha` action declared in the current controller.
-	 * This can also be a route consisting of controller ID and action ID (e.g. 'site/captcha').
+	 * @var string the route of the controller action that renders the CAPTCHA image.
 	 */
-	public $captchaAction = 'captcha';
+	public $captchaAction = 'site/captcha';
+
+
 	/**
-	 * @var boolean whether the attribute value can be null or empty.
-	 * Defaults to false, meaning the attribute is invalid if it is empty.
+	 * Initializes the validator.
 	 */
-	public $allowEmpty = false;
+	public function init()
+	{
+		parent::init();
+		if ($this->message === null) {
+			$this->message = Yii::t('yii|The verification code is incorrect.');
+		}
+	}
 
 	/**
 	 * Validates the attribute of the object.
@@ -42,36 +50,38 @@ class CaptchaValidator extends Validator
 	public function validateAttribute($object, $attribute)
 	{
 		$value = $object->$attribute;
-		if ($this->allowEmpty && $this->isEmpty($value)) {
-			return;
+		if (!$this->validateValue($value)) {
+			$this->addError($object, $attribute, $this->message);
 		}
+	}
+
+	/**
+	 * Validates the given value.
+	 * @param mixed $value the value to be validated.
+	 * @return boolean whether the value is valid.
+	 */
+	public function validateValue($value)
+	{
 		$captcha = $this->getCaptchaAction();
-		if (!$captcha->validate($value, $this->caseSensitive)) {
-			$message = $this->message !== null ? $this->message : \Yii::t('yii|The verification code is incorrect.');
-			$this->addError($object, $attribute, $message);
-		}
+		return !is_array($value) && $captcha->validate($value, $this->caseSensitive);
 	}
 
 	/**
 	 * Returns the CAPTCHA action object.
-	 * @return CCaptchaAction the action object
+	 * @return CaptchaAction the action object
 	 */
 	public function getCaptchaAction()
 	{
-		if (strpos($this->captchaAction, '/') !== false) {  // contains controller or module
-			$ca = \Yii::$app->createController($this->captchaAction);
-			if ($ca !== null) {
-				list($controller, $actionID) = $ca;
-				$action = $controller->createAction($actionID);
+		$ca = Yii::$app->createController($this->captchaAction);
+		if ($ca !== false) {
+			/** @var \yii\base\Controller $controller */
+			list($controller, $actionID) = $ca;
+			$action = $controller->createAction($actionID);
+			if ($action !== null) {
+				return $action;
 			}
-		} else {
-			$action = \Yii::$app->getController()->createAction($this->captchaAction);
-		}
-
-		if ($action === null) {
-			throw new \yii\base\Exception('Invalid captcha action ID: ' . $this->captchaAction);
 		}
-		return $action;
+		throw new InvalidConfigException('Invalid CAPTCHA action ID: ' . $this->captchaAction);
 	}
 
 	/**
@@ -83,8 +93,7 @@ class CaptchaValidator extends Validator
 	public function clientValidateAttribute($object, $attribute)
 	{
 		$captcha = $this->getCaptchaAction();
-		$message = $this->message !== null ? $this->message : \Yii::t('yii|The verification code is incorrect.');
-		$message = strtr($message, array(
+		$message = strtr($this->message, array(
 			'{attribute}' => $object->getAttributeLabel($attribute),
 			'{value}' => $object->$attribute,
 		));
@@ -102,7 +111,7 @@ if(h != hash) {
 }
 ";
 
-		if ($this->allowEmpty) {
+		if ($this->skipOnEmpty) {
 			$js = "
 if($.trim(value)!='') {
 	$js
diff --git a/framework/validators/CompareValidator.php b/framework/validators/CompareValidator.php
index 43f2edf..1df09c4 100644
--- a/framework/validators/CompareValidator.php
+++ b/framework/validators/CompareValidator.php
@@ -6,6 +6,7 @@
  */
 
 namespace yii\validators;
+
 use Yii;
 use yii\base\InvalidConfigException;
 
@@ -45,23 +46,12 @@ class CompareValidator extends Validator
 	 */
 	public $compareValue;
 	/**
-	 * @var boolean whether the comparison is strict (both value and type must be the same.)
-	 * Defaults to false.
-	 */
-	public $strict = false;
-	/**
-	 * @var boolean whether the attribute value can be null or empty. Defaults to false.
-	 * If this is true, it means the attribute is considered valid when it is empty.
-	 */
-	public $allowEmpty = false;
-	/**
-	 * @var string the operator for comparison. Defaults to '='.
-	 * The followings are valid operators:
-	 * 
-	 * - `=` or `==`: validates to see if the two values are equal. If [[strict]] is true, the comparison
-	 *   will be done in strict mode (i.e. checking value type as well).
-	 * - `!=`: validates to see if the two values are NOT equal. If [[strict]] is true, the comparison
-	 *   will be done in strict mode (i.e. checking value type as well).
+	 * @var string the operator for comparison. The following operators are supported:
+	 *
+	 * - '==': validates to see if the two values are equal. The comparison is done is non-strict mode.
+	 * - '===': validates to see if the two values are equal. The comparison is done is strict mode.
+	 * - '!=': validates to see if the two values are NOT equal. The comparison is done is non-strict mode.
+	 * - '!==': validates to see if the two values are NOT equal. The comparison is done is strict mode.
 	 * - `>`: validates to see if the value being validated is greater than the value being compared with.
 	 * - `>=`: validates to see if the value being validated is greater than or equal to the value being compared with.
 	 * - `<`: validates to see if the value being validated is less than the value being compared with.
@@ -69,6 +59,45 @@ class CompareValidator extends Validator
 	 */
 	public $operator = '=';
 
+
+	/**
+	 * Initializes the validator.
+	 */
+	public function init()
+	{
+		parent::init();
+		if ($this->message === null) {
+			switch ($this->operator) {
+				case '==':
+					$this->message = Yii::t('yii|{attribute} must be repeated exactly.');
+					break;
+				case '===':
+					$this->message = Yii::t('yii|{attribute} must be repeated exactly.');
+					break;
+				case '!=':
+					$this->message = Yii::t('yii|{attribute} must not be equal to "{compareValue}".');
+					break;
+				case '!==':
+					$this->message = Yii::t('yii|{attribute} must not be equal to "{compareValue}".');
+					break;
+				case '>':
+					$this->message = Yii::t('yii|{attribute} must be greater than "{compareValue}".');
+					break;
+				case '>=':
+					$this->message = Yii::t('yii|{attribute} must be greater than or equal to "{compareValue}".');
+					break;
+				case '<':
+					$this->message = Yii::t('yii|{attribute} must be less than "{compareValue}".');
+					break;
+				case '<=':
+					$this->message = Yii::t('yii|{attribute} must be less than or equal to "{compareValue}".');
+					break;
+				default:
+					throw new InvalidConfigException("Unknown operator: {$this->operator}");
+			}
+		}
+	}
+
 	/**
 	 * Validates the attribute of the object.
 	 * If there is any error, the error message is added to the object.
@@ -79,7 +108,8 @@ class CompareValidator extends Validator
 	public function validateAttribute($object, $attribute)
 	{
 		$value = $object->$attribute;
-		if ($this->allowEmpty && $this->isEmpty($value)) {
+		if (is_array($value)) {
+			$this->addError($object, $attribute, Yii::t('yii|{attribute} is invalid.'));
 			return;
 		}
 		if ($this->compareValue !== null) {
@@ -91,45 +121,45 @@ class CompareValidator extends Validator
 		}
 
 		switch ($this->operator) {
-			case '=':
-			case '==':
-				if (($this->strict && $value !== $compareValue) || (!$this->strict && $value != $compareValue)) {
-					$message = ($this->message !== null) ? $this->message : Yii::t('yii|{attribute} must be repeated exactly.');
-					$this->addError($object, $attribute, $message, array('{compareAttribute}' => $compareLabel));
-				}
-				break;
-			case '!=':
-				if (($this->strict && $value === $compareValue) || (!$this->strict && $value == $compareValue)) {
-					$message = ($this->message !== null) ? $this->message : Yii::t('yii|{attribute} must not be equal to "{compareValue}".');
-					$this->addError($object, $attribute, $message, array('{compareAttribute}' => $compareLabel, '{compareValue}' => $compareValue));
-				}
-				break;
-			case '>':
-				if ($value <= $compareValue) {
-					$message = ($this->message !== null) ? $this->message : Yii::t('yii|{attribute} must be greater than "{compareValue}".');
-					$this->addError($object, $attribute, $message, array('{compareAttribute}' => $compareLabel, '{compareValue}' => $compareValue));
-				}
-				break;
-			case '>=':
-				if ($value < $compareValue) {
-					$message = ($this->message !== null) ? $this->message : Yii::t('yii|{attribute} must be greater than or equal to "{compareValue}".');
-					$this->addError($object, $attribute, $message, array('{compareAttribute}' => $compareLabel, '{compareValue}' => $compareValue));
-				}
-				break;
-			case '<':
-				if ($value >= $compareValue) {
-					$message = ($this->message !== null) ? $this->message : Yii::t('yii|{attribute} must be less than "{compareValue}".');
-					$this->addError($object, $attribute, $message, array('{compareAttribute}' => $compareLabel, '{compareValue}' => $compareValue));
-				}
-				break;
-			case '<=':
-				if ($value > $compareValue) {
-					$message = ($this->message !== null) ? $this->message : Yii::t('yii|{attribute} must be less than or equal to "{compareValue}".');
-					$this->addError($object, $attribute, $message, array('{compareAttribute}' => $compareLabel, '{compareValue}' => $compareValue));
-				}
-				break;
-			default:
-				throw new InvalidConfigException("Unknown operator: {$this->operator}");
+			case '==': $valid = $value == $compareValue; break;
+			case '===': $valid = $value === $compareValue; break;
+			case '!=': $valid = $value != $compareValue; break;
+			case '!==': $valid = $value !== $compareValue; break;
+			case '>': $valid = $value > $compareValue; break;
+			case '>=': $valid = $value >= $compareValue; break;
+			case '<': $valid = $value < $compareValue; break;
+			case '<=': $valid = $value <= $compareValue; break;
+			default: $valid = false; break;
+		}
+		if (!$valid) {
+			$this->addError($object, $attribute, $this->message, array(
+				'{compareAttribute}' => $compareLabel,
+				'{compareValue}' => $compareValue,
+			));
+		}
+	}
+
+	/**
+	 * Validates the given value.
+	 * @param mixed $value the value to be validated.
+	 * @return boolean whether the value is valid.
+	 * @throws InvalidConfigException if [[compareValue]] is not set.
+	 */
+	public function validateValue($value)
+	{
+		if ($this->compareValue === null) {
+			throw new InvalidConfigException('CompareValidator::compareValue must be set.');
+		}
+
+		switch ($this->operator) {
+			case '==': return $value == $this->compareValue;
+			case '===': return $value === $this->compareValue;
+			case '!=': return $value != $this->compareValue;
+			case '!==': return $value !== $this->compareValue;
+			case '>': return $value > $this->compareValue;
+			case '>=': return $value >= $this->compareValue;
+			case '<': return $value < $this->compareValue;
+			case '<=': return $value <= $this->compareValue;
 		}
 	}
 
@@ -150,57 +180,14 @@ class CompareValidator extends Validator
 			$compareValue = "\$('#" . (CHtml::activeId($object, $compareAttribute)) . "').val()";
 			$compareLabel = $object->getAttributeLabel($compareAttribute);
 		}
-
-		$message = $this->message;
-		switch ($this->operator) {
-			case '=':
-			case '==':
-				if ($message === null) {
-					$message = Yii::t('yii|{attribute} must be repeated exactly.');
-				}
-				$condition = 'value!=' . $compareValue;
-				break;
-			case '!=':
-				if ($message === null) {
-					$message = Yii::t('yii|{attribute} must not be equal to "{compareValue}".');
-				}
-				$condition = 'value==' . $compareValue;
-				break;
-			case '>':
-				if ($message === null) {
-					$message = Yii::t('yii|{attribute} must be greater than "{compareValue}".');
-				}
-				$condition = 'value<=' . $compareValue;
-				break;
-			case '>=':
-				if ($message === null) {
-					$message = Yii::t('yii|{attribute} must be greater than or equal to "{compareValue}".');
-				}
-				$condition = 'value<' . $compareValue;
-				break;
-			case '<':
-				if ($message === null) {
-					$message = Yii::t('yii|{attribute} must be less than "{compareValue}".');
-				}
-				$condition = 'value>=' . $compareValue;
-				break;
-			case '<=':
-				if ($message === null) {
-					$message = Yii::t('yii|{attribute} must be less than or equal to "{compareValue}".');
-				}
-				$condition = 'value>' . $compareValue;
-				break;
-			default:
-				throw new InvalidConfigException("Unknown operator: {$this->operator}");
-		}
-
-		$message = strtr($message, array(
+		$condition = "value {$this->operator} $compareValue";
+		$message = strtr($this->message, array(
 			'{attribute}' => $object->getAttributeLabel($attribute),
 			'{compareValue}' => $compareLabel,
 		));
 
 		return "
-if (" . ($this->allowEmpty ? "$.trim(value)!='' && " : '') . $condition . ") {
+if (" . ($this->skipOnEmpty ? "$.trim(value)!='' && " : '') . $condition . ") {
 	messages.push(" . json_encode($message) . ");
 }
 ";
diff --git a/framework/validators/DateValidator.php b/framework/validators/DateValidator.php
index 7899c95..7c3b181 100644
--- a/framework/validators/DateValidator.php
+++ b/framework/validators/DateValidator.php
@@ -7,11 +7,11 @@
 
 namespace yii\validators;
 
+use Yii;
+use DateTime;
+
 /**
- * DateValidator verifies if the attribute represents a date, time or datetime.
- *
- * By setting the {@link format} property, one can specify what format the date value
- * must be in. If the given date value doesn't follow the format, the attribute is considered as invalid.
+ * DateValidator verifies if the attribute represents a date, time or datetime in a proper format.
  *
  * @author Qiang Xue <qiang.xue@gmail.com>
  * @since 2.0
@@ -19,17 +19,11 @@ namespace yii\validators;
 class DateValidator extends Validator
 {
 	/**
-	 * @var mixed the format pattern that the date value should follow.
-	 * This can be either a string or an array representing multiple formats.
-	 * Defaults to 'MM/dd/yyyy'. Please see {@link CDateTimeParser} for details
-	 * about how to specify a date format.
-	 */
-	public $format = 'MM/dd/yyyy';
-	/**
-	 * @var boolean whether the attribute value can be null or empty. Defaults to true,
-	 * meaning that if the attribute is empty, it is considered valid.
+	 * @var string the date format that the value being validated should follow.
+	 * Please refer to [[http://www.php.net/manual/en/datetime.createfromformat.php]] on
+	 * supported formats.
 	 */
-	public $allowEmpty = true;
+	public $format = 'Y-m-d';
 	/**
 	 * @var string the name of the attribute to receive the parsing result.
 	 * When this property is not null and the validation is successful, the named attribute will
@@ -38,6 +32,17 @@ class DateValidator extends Validator
 	public $timestampAttribute;
 
 	/**
+	 * Initializes the validator.
+	 */
+	public function init()
+	{
+		parent::init();
+		if ($this->message === null) {
+			$this->message = Yii::t('yii|The format of {attribute} is invalid.');
+		}
+	}
+
+	/**
 	 * Validates the attribute of the object.
 	 * If there is any error, the error message is added to the object.
 	 * @param \yii\base\Model $object the object being validated
@@ -46,27 +51,26 @@ class DateValidator extends Validator
 	public function validateAttribute($object, $attribute)
 	{
 		$value = $object->$attribute;
-		if ($this->allowEmpty && $this->isEmpty($value)) {
+		if (is_array($value)) {
+			$this->addError($object, $attribute, $this->message);
 			return;
 		}
-
-		$formats = is_string($this->format) ? array($this->format) : $this->format;
-		$valid = false;
-		foreach ($formats as $format) {
-			$timestamp = CDateTimeParser::parse($value, $format, array('month' => 1, 'day' => 1, 'hour' => 0, 'minute' => 0, 'second' => 0));
-			if ($timestamp !== false) {
-				$valid = true;
-				if ($this->timestampAttribute !== null) {
-					$object-> {$this->timestampAttribute} = $timestamp;
-				}
-				break;
-			}
+		$date = DateTime::createFromFormat($this->format, $value);
+		if ($date === false) {
+			$this->addError($object, $attribute, $this->message);
+		} elseif ($this->timestampAttribute !== false) {
+			$object->{$this->timestampAttribute} = $date->getTimestamp();
 		}
+	}
 
-		if (!$valid) {
-			$message = ($this->message !== null) ? $this->message : \Yii::t('yii|The format of {attribute} is invalid.');
-			$this->addError($object, $attribute, $message);
-		}
+	/**
+	 * Validates the given value.
+	 * @param mixed $value the value to be validated.
+	 * @return boolean whether the value is valid.
+	 */
+	public function validateValue($value)
+	{
+		return DateTime::createFromFormat($this->format, $value) !== false;
 	}
 }
 
diff --git a/framework/validators/DefaultValueValidator.php b/framework/validators/DefaultValueValidator.php
index be06768..185dbd4 100644
--- a/framework/validators/DefaultValueValidator.php
+++ b/framework/validators/DefaultValueValidator.php
@@ -10,12 +10,8 @@ namespace yii\validators;
 /**
  * DefaultValueValidator sets the attribute to be the specified default value.
  *
- * By default, when the attribute being validated is [[isEmpty|empty]], the validator
- * will assign a default [[value]] to it. However, if [[setOnEmpty]] is false, the validator
- * will always assign the default [[value]] to the attribute, no matter it is empty or not.
- *
  * DefaultValueValidator is not really a validator. It is provided mainly to allow
- * specifying attribute default values in a dynamic way.
+ * specifying attribute default values when they are empty.
  *
  * @author Qiang Xue <qiang.xue@gmail.com>
  * @since 2.0
@@ -27,11 +23,10 @@ class DefaultValueValidator extends Validator
 	 */
 	public $value;
 	/**
-	 * @var boolean whether to set the default [[value]] only when the attribute is [[isEmpty|empty]].
-	 * Defaults to true. If false, the attribute will always be assigned with the default [[value]],
-	 * no matter it is empty or not.
+	 * @var boolean this property is overwritten to be false so that this validator will
+	 * be applied when the value being validated is empty.
 	 */
-	public $setOnEmpty = true;
+	public $skipOnEmpty = false;
 
 	/**
 	 * Validates the attribute of the object.
@@ -40,7 +35,7 @@ class DefaultValueValidator extends Validator
 	 */
 	public function validateAttribute($object, $attribute)
 	{
-		if (!$this->setOnEmpty || $this->isEmpty($object->$attribute)) {
+		if ($this->isEmpty($object->$attribute)) {
 			$object->$attribute = $this->value;
 		}
 	}
diff --git a/framework/validators/EmailValidator.php b/framework/validators/EmailValidator.php
index d1d2257..e498975 100644
--- a/framework/validators/EmailValidator.php
+++ b/framework/validators/EmailValidator.php
@@ -7,6 +7,8 @@
 
 namespace yii\validators;
 
+use Yii;
+
 /**
  * EmailValidator validates that the attribute value is a valid email address.
  *
@@ -42,11 +44,17 @@ class EmailValidator extends Validator
 	 * Defaults to false.
 	 */
 	public $checkPort = false;
+
 	/**
-	 * @var boolean whether the attribute value can be null or empty. Defaults to true,
-	 * meaning that if the attribute is empty, it is considered valid.
+	 * Initializes the validator.
 	 */
-	public $allowEmpty = true;
+	public function init()
+	{
+		parent::init();
+		if ($this->message === null) {
+			$this->message = Yii::t('yii|{attribute} is not a valid email address.');
+		}
+	}
 
 	/**
 	 * Validates the attribute of the object.
@@ -57,21 +65,15 @@ class EmailValidator extends Validator
 	public function validateAttribute($object, $attribute)
 	{
 		$value = $object->$attribute;
-		if ($this->allowEmpty && $this->isEmpty($value)) {
-			return;
-		}
 		if (!$this->validateValue($value)) {
-			$message = ($this->message !== null) ? $this->message : \Yii::t('yii|{attribute} is not a valid email address.');
-			$this->addError($object, $attribute, $message);
+			$this->addError($object, $attribute, $this->message);
 		}
 	}
 
 	/**
-	 * Validates a static value to see if it is a valid email.
-	 * Note that this method does not respect [[allowEmpty]] property.
-	 * This method is provided so that you can call it directly without going through the model validation rule mechanism.
-	 * @param mixed $value the value to be validated
-	 * @return boolean whether the value is a valid email
+	 * Validates the given value.
+	 * @param mixed $value the value to be validated.
+	 * @return boolean whether the value is valid.
 	 */
 	public function validateValue($value)
 	{
@@ -98,8 +100,7 @@ class EmailValidator extends Validator
 	 */
 	public function clientValidateAttribute($object, $attribute)
 	{
-		$message = ($this->message !== null) ? $this->message : \Yii::t('yii|{attribute} is not a valid email address.');
-		$message = strtr($message, array(
+		$message = strtr($this->message, array(
 			'{attribute}' => $object->getAttributeLabel($attribute),
 			'{value}' => $object->$attribute,
 		));
@@ -110,7 +111,7 @@ class EmailValidator extends Validator
 		}
 
 		return "
-if(" . ($this->allowEmpty ? "$.trim(value)!='' && " : '') . $condition . ") {
+if(" . ($this->skipOnEmpty ? "$.trim(value)!='' && " : '') . $condition . ") {
 	messages.push(" . json_encode($message) . ");
 }
 ";
diff --git a/framework/validators/ExistValidator.php b/framework/validators/ExistValidator.php
index 8df3e19..7aa434c 100644
--- a/framework/validators/ExistValidator.php
+++ b/framework/validators/ExistValidator.php
@@ -6,6 +6,8 @@
  */
 
 namespace yii\validators;
+
+use Yii;
 use yii\base\InvalidConfigException;
 
 /**
@@ -34,11 +36,18 @@ class ExistValidator extends Validator
 	 * @see className
 	 */
 	public $attributeName;
+
+
 	/**
-	 * @var boolean whether the attribute value can be null or empty. Defaults to true,
-	 * meaning that if the attribute is empty, it is considered valid.
+	 * Initializes the validator.
 	 */
-	public $allowEmpty = true;
+	public function init()
+	{
+		parent::init();
+		if ($this->message === null) {
+			$this->message = Yii::t('yii|{attribute} is invalid.');
+		}
+	}
 
 	/**
 	 * Validates the attribute of the object.
@@ -46,29 +55,48 @@ class ExistValidator extends Validator
 	 *
 	 * @param \yii\db\ActiveRecord $object the object being validated
 	 * @param string $attribute the attribute being validated
-	 * @throws InvalidConfigException if table doesn't have column specified
 	 */
 	public function validateAttribute($object, $attribute)
 	{
 		$value = $object->$attribute;
-		if ($this->allowEmpty && $this->isEmpty($value)) {
+
+		if (is_array($value)) {
+			$this->addError($object, $attribute, $this->message);
 			return;
 		}
 
 		/** @var $className \yii\db\ActiveRecord */
-		$className = ($this->className === null) ? get_class($object) : \Yii::import($this->className);
-		$attributeName = ($this->attributeName === null) ? $attribute : $this->attributeName;
-		$table = $className::getTableSchema();
-		if (($column = $table->getColumn($attributeName)) === null) {
-			throw new InvalidConfigException('Table "' . $table->name . '" does not have a column named "' . $attributeName . '"');
-		}
-
+		$className = $this->className === null ? get_class($object) : Yii::import($this->className);
+		$attributeName = $this->attributeName === null ? $attribute : $this->attributeName;
 		$query = $className::find();
-		$query->where(array($column->name => $value));
+		$query->where(array($attributeName => $value));
 		if (!$query->exists()) {
-			$message = ($this->message !== null) ? $this->message : \Yii::t('yii|{attribute} "{value}" is invalid.');
-			$this->addError($object, $attribute, $message);
+			$this->addError($object, $attribute, $this->message);
 		}
 	}
+
+	/**
+	 * Validates the given value.
+	 * @param mixed $value the value to be validated.
+	 * @return boolean whether the value is valid.
+	 * @throws InvalidConfigException if either [[className]] or [[attributeName]] is not set.
+	 */
+	public function validateValue($value)
+	{
+		if (is_array($value)) {
+			return false;
+		}
+		if ($this->className === null) {
+			throw new InvalidConfigException('The "className" property must be set.');
+		}
+		if ($this->attributeName === null) {
+			throw new InvalidConfigException('The "attributeName" property must be set.');
+		}
+		/** @var $className \yii\db\ActiveRecord */
+		$className = $this->className;
+		$query = $className::find();
+		$query->where(array($this->attributeName => $value));
+		return $query->exists();
+	}
 }
 
diff --git a/framework/validators/FileValidator.php b/framework/validators/FileValidator.php
index b05ac2a..c104c05 100644
--- a/framework/validators/FileValidator.php
+++ b/framework/validators/FileValidator.php
@@ -7,47 +7,19 @@
 
 namespace yii\validators;
 
+use Yii;
+use yii\helpers\FileHelper;
+use yii\web\UploadedFile;
+
 /**
- * CFileValidator verifies if an attribute is receiving a valid uploaded file.
- *
- * It uses the model class and attribute name to retrieve the information
- * about the uploaded file. It then checks if a file is uploaded successfully,
- * if the file size is within the limit and if the file type is allowed.
- *
- * This validator will attempt to fetch uploaded data if attribute is not
- * previously set. Please note that this cannot be done if input is tabular:
- * <pre>
- *  foreach($models as $i=>$model)
- *     $model->attribute = CUploadedFile::getInstance($model, "[$i]attribute");
- * </pre>
- * Please note that you must use {@link CUploadedFile::getInstances} for multiple
- * file uploads.
- *
- * When using CFileValidator with an active record, the following code is often used:
- * <pre>
- *  if($model->save())
- *  {
- *     // single upload
- *     $model->attribute->saveAs($path);
- *     // multiple upload
- *     foreach($model->attribute as $file)
- *        $file->saveAs($path);
- *  }
- * </pre>
- *
- * You can use {@link CFileValidator} to validate the file attribute.
+ * FileValidator verifies if an attribute is receiving a valid uploaded file.
  *
  * @author Qiang Xue <qiang.xue@gmail.com>
  * @since 2.0
  */
-class CFileValidator extends Validator
+class FileValidator extends Validator
 {
 	/**
-	 * @var boolean whether the attribute requires a file to be uploaded or not.
-	 * Defaults to false, meaning a file is required to be uploaded.
-	 */
-	public $allowEmpty = false;
-	/**
 	 * @var mixed a list of file name extensions that are allowed to be uploaded.
 	 * This can be either an array or a string consisting of file extension names
 	 * separated by space or comma (e.g. "gif, jpg").
@@ -66,136 +38,179 @@ class CFileValidator extends Validator
 	 * Defaults to null, meaning no limit.
 	 * Note, the size limit is also affected by 'upload_max_filesize' INI setting
 	 * and the 'MAX_FILE_SIZE' hidden field value.
-	 * @see tooLarge
+	 * @see tooBig
 	 */
 	public $maxSize;
 	/**
+	 * @var integer the maximum file count the given attribute can hold.
+	 * It defaults to 1, meaning single file upload. By defining a higher number,
+	 * multiple uploads become possible.
+	 */
+	public $maxFiles = 1;
+	/**
+	 * @var string the error message used when a file is not uploaded correctly.
+	 */
+	public $message;
+	/**
+	 * @var string the error message used when no file is uploaded.
+	 */
+	public $uploadRequired;
+	/**
 	 * @var string the error message used when the uploaded file is too large.
-	 * @see maxSize
+	 * You may use the following tokens in the message:
+	 *
+	 * - {attribute}: the attribute name
+	 * - {file}: the uploaded file name
+	 * - {limit}: the maximum size allowed (see [[getSizeLimit()]])
 	 */
-	public $tooLarge;
+	public $tooBig;
 	/**
 	 * @var string the error message used when the uploaded file is too small.
-	 * @see minSize
+	 * You may use the following tokens in the message:
+	 *
+	 * - {attribute}: the attribute name
+	 * - {file}: the uploaded file name
+	 * - {limit}: the value of [[minSize]]
 	 */
 	public $tooSmall;
 	/**
 	 * @var string the error message used when the uploaded file has an extension name
-	 * that is not listed among {@link extensions}.
+	 * that is not listed in [[extensions]]. You may use the following tokens in the message:
+	 *
+	 * - {attribute}: the attribute name
+	 * - {extensions}: the list of the allowed extensions.
 	 */
 	public $wrongType;
 	/**
-	 * @var integer the maximum file count the given attribute can hold.
-	 * It defaults to 1, meaning single file upload. By defining a higher number,
-	 * multiple uploads become possible.
-	 */
-	public $maxFiles = 1;
-	/**
-	 * @var string the error message used if the count of multiple uploads exceeds
-	 * limit.
+	 * @var string the error message used if the count of multiple uploads exceeds limit.
+	 * You may use the following tokens in the message:
+	 *
+	 * - {attribute}: the attribute name
+	 * - {file}: the uploaded file name
+	 * - {limit}: the value of [[maxFiles]]
 	 */
 	public $tooMany;
 
 	/**
-	 * Set the attribute and then validates using {@link validateFile}.
-	 * If there is any error, the error message is added to the object.
-	 * @param \yii\base\Model $object the object being validated
-	 * @param string $attribute the attribute being validated
+	 * Initializes the validator.
 	 */
-	public function validateAttribute($object, $attribute)
+	public function init()
 	{
-		if ($this->maxFiles > 1)
-		{
-			$files = $object->$attribute;
-			if (!is_array($files) || !isset($files[0]) || !$files[0] instanceof CUploadedFile)
-				$files = CUploadedFile::getInstances($object, $attribute);
-			if (array() === $files)
-				return $this->emptyAttribute($object, $attribute);
-			if (count($files) > $this->maxFiles)
-			{
-				$message = $this->tooMany !== null ? $this->tooMany : \Yii::t('yii|{attribute} cannot accept more than {limit} files.');
-				$this->addError($object, $attribute, $message, array('{attribute}' => $attribute, '{limit}' => $this->maxFiles));
-			} else
-				foreach ($files as $file)
-					$this->validateFile($object, $attribute, $file);
-		} else
-		{
-			$file = $object->$attribute;
-			if (!$file instanceof CUploadedFile)
-			{
-				$file = CUploadedFile::getInstance($object, $attribute);
-				if (null === $file)
-					return $this->emptyAttribute($object, $attribute);
-			}
-			$this->validateFile($object, $attribute, $file);
+		parent::init();
+		if ($this->message === null) {
+			$this->message = Yii::t('yii|File upload failed.');
+		}
+		if ($this->uploadRequired === null) {
+			$this->uploadRequired = Yii::t('yii|Please upload a file.');
 		}
+		if ($this->tooMany === null) {
+			$this->tooMany = Yii::t('yii|You can upload at most {limit} files.');
+		}
+		if ($this->wrongType === null) {
+			$this->wrongType = Yii::t('yii|Only files with these extensions are allowed: {extensions}.');
+		}
+		if ($this->tooBig === null) {
+			$this->tooBig = Yii::t('yii|The file "{file}" is too big. Its size cannot exceed {limit} bytes.');
+		}
+		if ($this->tooSmall === null) {
+			$this->tooSmall = Yii::t('yii|The file "{file}" is too small. Its size cannot be smaller than {limit} bytes.');
+		}
+		if (!is_array($this->types)) {
+			$this->types = preg_split('/[\s,]+/', strtolower($this->types), -1, PREG_SPLIT_NO_EMPTY);
+		}		
 	}
 
 	/**
-	 * Internally validates a file object.
+	 * Validates the attribute.
 	 * @param \yii\base\Model $object the object being validated
 	 * @param string $attribute the attribute being validated
-	 * @param CUploadedFile $file uploaded file passed to check against a set of rules
 	 */
-	public function validateFile($object, $attribute, $file)
+	public function validateAttribute($object, $attribute)
 	{
-		if (null === $file || ($error = $file->getError()) == UPLOAD_ERR_NO_FILE)
-			return $this->emptyAttribute($object, $attribute);
-		elseif ($error == UPLOAD_ERR_INI_SIZE || $error == UPLOAD_ERR_FORM_SIZE || $this->maxSize !== null && $file->getSize() > $this->maxSize)
-		{
-			$message = $this->tooLarge !== null ? $this->tooLarge : \Yii::t('yii|The file "{file}" is too large. Its size cannot exceed {limit} bytes.');
-			$this->addError($object, $attribute, $message, array('{file}' => $file->getName(), '{limit}' => $this->getSizeLimit()));
-		} elseif ($error == UPLOAD_ERR_PARTIAL)
-			throw new CException(\Yii::t('yii|The file "{file}" was only partially uploaded.', array('{file}' => $file->getName())));
-		elseif ($error == UPLOAD_ERR_NO_TMP_DIR)
-			throw new CException(\Yii::t('yii|Missing the temporary folder to store the uploaded file "{file}".', array('{file}' => $file->getName())));
-		elseif ($error == UPLOAD_ERR_CANT_WRITE)
-			throw new CException(\Yii::t('yii|Failed to write the uploaded file "{file}" to disk.', array('{file}' => $file->getName())));
-		elseif (defined('UPLOAD_ERR_EXTENSION') && $error == UPLOAD_ERR_EXTENSION)  // available for PHP 5.2.0 or above
-			throw new CException(\Yii::t('yii|File upload was stopped by extension.'));
-
-		if ($this->minSize !== null && $file->getSize() < $this->minSize)
-		{
-			$message = $this->tooSmall !== null ? $this->tooSmall : \Yii::t('yii|The file "{file}" is too small. Its size cannot be smaller than {limit} bytes.');
-			$this->addError($object, $attribute, $message, array('{file}' => $file->getName(), '{limit}' => $this->minSize));
-		}
-
-		if ($this->types !== null)
-		{
-			if (is_string($this->types))
-				$types = preg_split('/[\s,]+/', strtolower($this->types), -1, PREG_SPLIT_NO_EMPTY);
-			else
-				$types = $this->types;
-			if (!in_array(strtolower($file->getExtensionName()), $types))
-			{
-				$message = $this->wrongType !== null ? $this->wrongType : \Yii::t('yii|The file "{file}" cannot be uploaded. Only files with these extensions are allowed: {extensions}.');
-				$this->addError($object, $attribute, $message, array('{file}' => $file->getName(), '{extensions}' => implode(', ', $types)));
+		if ($this->maxFiles > 1) {
+			$files = $object->$attribute;
+			if (!is_array($files)) {
+				$this->addError($object, $attribute, $this->uploadRequired);
+				return;
+			}
+			foreach ($files as $i => $file) {
+				if (!$file instanceof UploadedFile || $file->getError() == UPLOAD_ERR_NO_FILE) {
+					unset($files[$i]);
+				}
+			}
+			$object->$attribute = array_values($files);
+			if ($files === array()) {
+				$this->addError($object, $attribute, $this->uploadRequired);				
+			}
+			if (count($files) > $this->maxFiles) {
+				$this->addError($object, $attribute, $this->tooMany, array('{attribute}' => $attribute, '{limit}' => $this->maxFiles));
+			} else {
+				foreach ($files as $file) {
+					$this->validateFile($object, $attribute, $file);
+				}
+			}
+		} else {
+			$file = $object->$attribute;
+			if ($file instanceof UploadedFile && $file->getError() != UPLOAD_ERR_NO_FILE) {
+				$this->validateFile($object, $attribute, $file);
+			} else {
+				$this->addError($object, $attribute, $this->uploadRequired);				
 			}
 		}
 	}
 
 	/**
-	 * Raises an error to inform end user about blank attribute.
+	 * Internally validates a file object.
 	 * @param \yii\base\Model $object the object being validated
 	 * @param string $attribute the attribute being validated
+	 * @param UploadedFile $file uploaded file passed to check against a set of rules
 	 */
-	public function emptyAttribute($object, $attribute)
+	protected function validateFile($object, $attribute, $file)
 	{
-		if (!$this->allowEmpty)
-		{
-			$message = $this->message !== null ? $this->message : \Yii::t('yii|{attribute} cannot be blank.');
-			$this->addError($object, $attribute, $message);
+		switch ($file->getError()) {
+			case UPLOAD_ERR_OK:
+				if ($this->maxSize !== null && $file->getSize() > $this->maxSize) {
+					$this->addError($object, $attribute, $this->tooBig, array('{file}' => $file->getName(), '{limit}' => $this->getSizeLimit()));
+				}
+				if ($this->minSize !== null && $file->getSize() < $this->minSize) {
+					$this->addError($object, $attribute, $this->tooSmall, array('{file}' => $file->getName(), '{limit}' => $this->minSize));
+				}
+				if (!empty($this->types) && !in_array(strtolower(FileHelper::getExtension($file->getName())), $this->types, true)) {
+					$this->addError($object, $attribute, $this->wrongType, array('{file}' => $file->getName(), '{extensions}' => implode(', ', $this->types)));
+				}
+				break;
+			case UPLOAD_ERR_INI_SIZE:
+			case UPLOAD_ERR_FORM_SIZE:
+				$this->addError($object, $attribute, $this->tooBig, array('{file}' => $file->getName(), '{limit}' => $this->getSizeLimit()));
+				break;
+			case UPLOAD_ERR_PARTIAL:
+				$this->addError($object, $attribute, $this->message);
+				Yii::warning('File was only partially uploaded: ' . $file->getName(), __METHOD__);
+				break;
+			case UPLOAD_ERR_NO_TMP_DIR:
+				$this->addError($object, $attribute, $this->message);
+				Yii::warning('Missing the temporary folder to store the uploaded file: ' . $file->getName(), __METHOD__);
+				break;
+			case UPLOAD_ERR_CANT_WRITE:
+				$this->addError($object, $attribute, $this->message);
+				Yii::warning('Failed to write the uploaded file to disk: ', $file->getName(), __METHOD__);
+				break;
+			case UPLOAD_ERR_EXTENSION:
+				$this->addError($object, $attribute, $this->message);
+				Yii::warning('File upload was stopped by some PHP extension: ', $file->getName(), __METHOD__);
+				break;
+			default:
+				break;
 		}
 	}
 
 	/**
 	 * Returns the maximum size allowed for uploaded files.
 	 * This is determined based on three factors:
-	 * <ul>
-	 * <li>'upload_max_filesize' in php.ini</li>
-	 * <li>'MAX_FILE_SIZE' hidden field</li>
-	 * <li>{@link maxSize}</li>
-	 * </ul>
+	 *
+	 * - 'upload_max_filesize' in php.ini
+	 * - 'MAX_FILE_SIZE' hidden field
+	 * - [[maxSize]]
 	 *
 	 * @return integer the size limit for uploaded files.
 	 */
@@ -203,10 +218,12 @@ class CFileValidator extends Validator
 	{
 		$limit = ini_get('upload_max_filesize');
 		$limit = $this->sizeToBytes($limit);
-		if ($this->maxSize !== null && $limit > 0 && $this->maxSize < $limit)
+		if ($this->maxSize !== null && $limit > 0 && $this->maxSize < $limit) {
 			$limit = $this->maxSize;
-		if (isset($_POST['MAX_FILE_SIZE']) && $_POST['MAX_FILE_SIZE'] > 0 && $_POST['MAX_FILE_SIZE'] < $limit)
-			$limit = $_POST['MAX_FILE_SIZE'];
+		}
+		if (isset($_POST['MAX_FILE_SIZE']) && $_POST['MAX_FILE_SIZE'] > 0 && $_POST['MAX_FILE_SIZE'] < $limit) {
+			$limit = (int)$_POST['MAX_FILE_SIZE'];
+		}
 		return $limit;
 	}
 
@@ -218,12 +235,18 @@ class CFileValidator extends Validator
 	 */
 	private function sizeToBytes($sizeStr)
 	{
-		switch (substr($sizeStr, -1))
-		{
-			case 'M': case 'm': return (int)$sizeStr * 1048576;
-			case 'K': case 'k': return (int)$sizeStr * 1024;
-			case 'G': case 'g': return (int)$sizeStr * 1073741824;
-			default: return (int)$sizeStr;
+		switch (substr($sizeStr, -1)) {
+			case 'M':
+			case 'm':
+				return (int)$sizeStr * 1048576;
+			case 'K':
+			case 'k':
+				return (int)$sizeStr * 1024;
+			case 'G':
+			case 'g':
+				return (int)$sizeStr * 1073741824;
+			default:
+				return (int)$sizeStr;
 		}
 	}
 }
\ No newline at end of file
diff --git a/framework/validators/FilterValidator.php b/framework/validators/FilterValidator.php
index c891979..72a9a9d 100644
--- a/framework/validators/FilterValidator.php
+++ b/framework/validators/FilterValidator.php
@@ -38,6 +38,23 @@ class FilterValidator extends Validator
 	 * ~~~
 	 */
 	public $filter;
+	/**
+	 * @var boolean this property is overwritten to be false so that this validator will
+	 * be applied when the value being validated is empty.
+	 */
+	public $skipOnEmpty = false;
+
+	/**
+	 * Initializes the validator.
+	 * @throws InvalidConfigException if [[filter]] is not set.
+	 */
+	public function init()
+	{
+		parent::init();
+		if ($this->filter === null) {
+			throw new InvalidConfigException('The "filter" property must be set.');
+		}
+	}
 
 	/**
 	 * Validates the attribute of the object.
@@ -48,9 +65,6 @@ class FilterValidator extends Validator
 	 */
 	public function validateAttribute($object, $attribute)
 	{
-		if ($this->filter === null) {
-			throw new InvalidConfigException('The "filter" property must be specified with a valid callback.');
-		}
 		$object->$attribute = call_user_func($this->filter, $object->$attribute);
 	}
 }
diff --git a/framework/validators/InlineValidator.php b/framework/validators/InlineValidator.php
index 5c12d52..3689a2f 100644
--- a/framework/validators/InlineValidator.php
+++ b/framework/validators/InlineValidator.php
@@ -25,8 +25,9 @@ namespace yii\validators;
 class InlineValidator extends Validator
 {
 	/**
-	 * @var string the name of the validation method defined in the
-	 * \yii\base\Model class
+	 * @var string|\Closure an anonymous function or the name of a model class method that will be
+	 * called to perform the actual validation. Note that if you use anonymous function, you cannot
+	 * use `$this` in it unless you are using PHP 5.4 or above.
 	 */
 	public $method;
 	/**
@@ -34,8 +35,8 @@ class InlineValidator extends Validator
 	 */
 	public $params;
 	/**
-	 * @var string the name of the method that returns the client validation code (see [[clientValidateAttribute()]]
-	 * for details on how to return client validation code). The signature of the method should be like the following:
+	 * @var string|\Closure an anonymous function or the name of a model class method that returns the client validation code.
+	 * The signature of the method should be like the following:
 	 *
 	 * ~~~
 	 * function foo($attribute)
@@ -45,6 +46,8 @@ class InlineValidator extends Validator
 	 * ~~~
 	 *
 	 * where `$attribute` refers to the attribute name to be validated.
+	 *
+	 * Please refer to [[clientValidateAttribute()]] for details on how to return client validation code.
 	 */
 	public $clientValidate;
 
@@ -56,7 +59,10 @@ class InlineValidator extends Validator
 	public function validateAttribute($object, $attribute)
 	{
 		$method = $this->method;
-		$object->$method($attribute, $this->params);
+		if (is_string($method)) {
+			$method = array($object, $method);
+		}
+		call_user_func($method, $attribute, $this->params);
 	}
 
 	/**
@@ -82,7 +88,10 @@ class InlineValidator extends Validator
 	{
 		if ($this->clientValidate !== null) {
 			$method = $this->clientValidate;
-			return $object->$method($attribute);
+			if (is_string($method)) {
+				$method = array($object, $method);
+			}
+			return call_user_func($method, $attribute);
 		} else {
 			return null;
 		}
diff --git a/framework/validators/NumberValidator.php b/framework/validators/NumberValidator.php
index 89363fb..915419e 100644
--- a/framework/validators/NumberValidator.php
+++ b/framework/validators/NumberValidator.php
@@ -26,11 +26,6 @@ class NumberValidator extends Validator
 	 */
 	public $integerOnly = false;
 	/**
-	 * @var boolean whether the attribute value can be null or empty. Defaults to true,
-	 * meaning that if the attribute is empty, it is considered valid.
-	 */
-	public $allowEmpty = true;
-	/**
 	 * @var integer|float upper limit of the number. Defaults to null, meaning no upper limit.
 	 */
 	public $max;
@@ -58,6 +53,24 @@ class NumberValidator extends Validator
 
 
 	/**
+	 * Initializes the validator.
+	 */
+	public function init()
+	{
+		parent::init();
+		if ($this->message === null) {
+			$this->message = $this->integerOnly ? Yii::t('yii|{attribute} must be an integer.')
+				: Yii::t('yii|{attribute} must be a number.');
+		}
+		if ($this->min !== null && $this->tooSmall === null) {
+			$this->tooSmall = Yii::t('yii|{attribute} must be no less than {min}.');
+		}
+		if ($this->max !== null && $this->tooBig === null) {
+			$this->tooBig = Yii::t('yii|{attribute} must be no greater than {max}.');
+		}
+	}
+
+	/**
 	 * Validates the attribute of the object.
 	 * If there is any error, the error message is added to the object.
 	 * @param \yii\base\Model $object the object being validated
@@ -66,31 +79,35 @@ class NumberValidator extends Validator
 	public function validateAttribute($object, $attribute)
 	{
 		$value = $object->$attribute;
-		if ($this->allowEmpty && $this->isEmpty($value)) {
+		if (is_array($value)) {
+			$this->addError($object, $attribute, Yii::t('yii|{attribute} is invalid.'));
 			return;
 		}
-		if ($this->integerOnly) {
-			if (!preg_match($this->integerPattern, "$value")) {
-				$message = $this->message !== null ? $this->message : Yii::t('yii|{attribute} must be an integer.');
-				$this->addError($object, $attribute, $message);
-			}
-		} else {
-			if (!preg_match($this->numberPattern, "$value")) {
-				$message = $this->message !== null ? $this->message : Yii::t('yii|{attribute} must be a number.');
-				$this->addError($object, $attribute, $message);
-			}
+		$pattern = $this->integerOnly ? $this->integerPattern : $this->numberPattern;
+		if (!preg_match($pattern, "$value")) {
+			$this->addError($object, $attribute, $this->message);
 		}
 		if ($this->min !== null && $value < $this->min) {
-			$message = $this->tooSmall !== null ? $this->tooSmall : Yii::t('yii|{attribute} is too small (minimum is {min}).');
-			$this->addError($object, $attribute, $message, array('{min}' => $this->min));
+			$this->addError($object, $attribute, $this->tooSmall, array('{min}' => $this->min));
 		}
 		if ($this->max !== null && $value > $this->max) {
-			$message = $this->tooBig !== null ? $this->tooBig : Yii::t('yii|{attribute} is too big (maximum is {max}).');
-			$this->addError($object, $attribute, $message, array('{max}' => $this->max));
+			$this->addError($object, $attribute, $this->tooBig, array('{max}' => $this->max));
 		}
 	}
 
 	/**
+	 * Validates the given value.
+	 * @param mixed $value the value to be validated.
+	 * @return boolean whether the value is valid.
+	 */
+	public function validateValue($value)
+	{
+		return preg_match($this->integerOnly ? $this->integerPattern : $this->numberPattern, "$value")
+			&& ($this->min === null || $value >= $this->min)
+			&& ($this->max === null || $value <= $this->max);
+	}
+
+	/**
 	 * Returns the JavaScript needed for performing client-side validation.
 	 * @param \yii\base\Model $object the data object being validated
 	 * @param string $attribute the name of the attribute to be validated.
@@ -99,12 +116,7 @@ class NumberValidator extends Validator
 	public function clientValidateAttribute($object, $attribute)
 	{
 		$label = $object->getAttributeLabel($attribute);
-
-		if (($message = $this->message) === null) {
-			$message = $this->integerOnly ? Yii::t('yii|{attribute} must be an integer.')
-					: Yii::t('yii|{attribute} must be a number.');
-		}
-		$message = strtr($message, array(
+		$message = strtr($this->message, array(
 			'{attribute}' => $label,
 		));
 
@@ -115,10 +127,7 @@ if(!value.match($pattern)) {
 }
 ";
 		if ($this->min !== null) {
-			if (($tooSmall = $this->tooSmall) === null) {
-				$tooSmall = Yii::t('yii|{attribute} is too small (minimum is {min}).');
-			}
-			$tooSmall = strtr($tooSmall, array(
+			$tooSmall = strtr($this->tooSmall, array(
 				'{attribute}' => $label,
 				'{min}' => $this->min,
 			));
@@ -130,10 +139,7 @@ if(value<{$this->min}) {
 ";
 		}
 		if ($this->max !== null) {
-			if (($tooBig = $this->tooBig) === null) {
-				$tooBig = Yii::t('yii|{attribute} is too big (maximum is {max}).');
-			}
-			$tooBig = strtr($tooBig, array(
+			$tooBig = strtr($this->tooBig, array(
 				'{attribute}' => $label,
 				'{max}' => $this->max,
 			));
@@ -144,7 +150,7 @@ if(value>{$this->max}) {
 ";
 		}
 
-		if ($this->allowEmpty) {
+		if ($this->skipOnEmpty) {
 			$js = "
 if(jQuery.trim(value)!='') {
 	$js
diff --git a/framework/validators/RangeValidator.php b/framework/validators/RangeValidator.php
index e23567c..18742ae 100644
--- a/framework/validators/RangeValidator.php
+++ b/framework/validators/RangeValidator.php
@@ -6,6 +6,8 @@
  */
 
 namespace yii\validators;
+
+use Yii;
 use yii\base\InvalidConfigException;
 
 /**
@@ -29,58 +31,62 @@ class RangeValidator extends Validator
 	 */
 	public $strict = false;
 	/**
-	 * @var boolean whether the attribute value can be null or empty. Defaults to true,
-	 * meaning that if the attribute is empty, it is considered valid.
-	 */
-	public $allowEmpty = true;
-	/**
 	 * @var boolean whether to invert the validation logic. Defaults to false. If set to true,
 	 * the attribute value should NOT be among the list of values defined via [[range]].
 	 **/
  	public $not = false;
 
 	/**
+	 * Initializes the validator.
+	 * @throws InvalidConfigException if [[range]] is not set.
+	 */
+	public function init()
+	{
+		parent::init();
+		if (!is_array($this->range)) {
+			throw new InvalidConfigException('The "range" property must be set.');
+		}
+		if ($this->message === null) {
+			$this->message = Yii::t('yii|{attribute} is invalid.');
+		}
+	}
+
+	/**
 	 * Validates the attribute of the object.
 	 * If there is any error, the error message is added to the object.
 	 * @param \yii\base\Model $object the object being validated
 	 * @param string $attribute the attribute being validated
-	 * @throws InvalidConfigException if the "range" property is not an array
 	 */
 	public function validateAttribute($object, $attribute)
 	{
 		$value = $object->$attribute;
-		if ($this->allowEmpty && $this->isEmpty($value)) {
-			return;
-		}
-		if (!is_array($this->range)) {
-			throw new InvalidConfigException('The "range" property must be specified as an array.');
-		}
 		if (!$this->not && !in_array($value, $this->range, $this->strict)) {
-			$message = ($this->message !== null) ? $this->message : \Yii::t('yii|{attribute} should be in the list.');
-			$this->addError($object, $attribute, $message);
+			$this->addError($object, $attribute, $this->message);
 		} elseif ($this->not && in_array($value, $this->range, $this->strict)) {
-			$message = ($this->message !== null) ? $this->message : \Yii::t('yii|{attribute} should NOT be in the list.');
-			$this->addError($object, $attribute, $message);
+			$this->addError($object, $attribute, $this->message);
 		}
 	}
 
 	/**
+	 * Validates the given value.
+	 * @param mixed $value the value to be validated.
+	 * @return boolean whether the value is valid.
+	 */
+	public function validateValue($value)
+	{
+		return !$this->not && in_array($value, $this->range, $this->strict)
+			|| $this->not && !in_array($value, $this->range, $this->strict);
+	}
+
+	/**
 	 * Returns the JavaScript needed for performing client-side validation.
 	 * @param \yii\base\Model $object the data object being validated
 	 * @param string $attribute the name of the attribute to be validated.
 	 * @return string the client-side validation script.
-	 * @throws InvalidConfigException if the "range" property is not an array
 	 */
 	public function clientValidateAttribute($object, $attribute)
 	{
-		if (!is_array($this->range)) {
-			throw new InvalidConfigException('The "range" property must be specified as an array.');
-		}
-
-		if (($message = $this->message) === null) {
-			$message = $this->not ? \Yii::t('yii|{attribute} should NOT be in the list.') : \Yii::t('yii|{attribute} should be in the list.');
-		}
-		$message = strtr($message, array(
+		$message = strtr($this->message, array(
 			'{attribute}' => $object->getAttributeLabel($attribute),
 			'{value}' => $object->$attribute,
 		));
@@ -92,7 +98,7 @@ class RangeValidator extends Validator
 		$range = json_encode($range);
 
 		return "
-if (" . ($this->allowEmpty ? "$.trim(value)!='' && " : '') . ($this->not ? "$.inArray(value, $range)>=0" : "$.inArray(value, $range)<0") . ") {
+if (" . ($this->skipOnEmpty ? "$.trim(value)!='' && " : '') . ($this->not ? "$.inArray(value, $range)>=0" : "$.inArray(value, $range)<0") . ") {
 	messages.push(" . json_encode($message) . ");
 }
 ";
diff --git a/framework/validators/RegularExpressionValidator.php b/framework/validators/RegularExpressionValidator.php
index df2b657..6c69be3 100644
--- a/framework/validators/RegularExpressionValidator.php
+++ b/framework/validators/RegularExpressionValidator.php
@@ -7,6 +7,9 @@
 
 namespace yii\validators;
 
+use Yii;
+use yii\base\InvalidConfigException;
+
 /**
  * RegularExpressionValidator validates that the attribute value matches the specified [[pattern]].
  *
@@ -22,53 +25,63 @@ class RegularExpressionValidator extends Validator
 	 */
 	public $pattern;
 	/**
-	 * @var boolean whether the attribute value can be null or empty. Defaults to true,
-	 * meaning that if the attribute is empty, it is considered valid.
-	 */
-	public $allowEmpty = true;
-	/**
 	 * @var boolean whether to invert the validation logic. Defaults to false. If set to true,
 	 * the regular expression defined via [[pattern]] should NOT match the attribute value.
+	 * @throws InvalidConfigException if the "pattern" is not a valid regular expression
 	 **/
  	public $not = false;
 
 	/**
+	 * Initializes the validator.
+	 * @throws InvalidConfigException if [[pattern]] is not set.
+	 */
+	public function init()
+	{
+		parent::init();
+		if ($this->pattern === null) {
+			throw new InvalidConfigException('The "pattern" property must be set.');
+		}
+		if ($this->message === null) {
+			$this->message = Yii::t('yii|{attribute} is invalid.');
+		}
+	}
+
+	/**
 	 * Validates the attribute of the object.
 	 * If there is any error, the error message is added to the object.
 	 * @param \yii\base\Model $object the object being validated
 	 * @param string $attribute the attribute being validated
-	 * @throws \yii\base\Exception if the "pattern" is not a valid regular expression
 	 */
 	public function validateAttribute($object, $attribute)
 	{
 		$value = $object->$attribute;
-		if ($this->allowEmpty && $this->isEmpty($value)) {
-			return;
-		}
-		if ($this->pattern === null) {
-			throw new \yii\base\Exception('The "pattern" property must be specified with a valid regular expression.');
-		}
-		if ((!$this->not && !preg_match($this->pattern, $value)) || ($this->not && preg_match($this->pattern, $value))) {
-			$message = ($this->message !== null) ? $this->message : \Yii::t('yii|{attribute} is invalid.');
-			$this->addError($object, $attribute, $message);
+		if (!$this->validateValue($value)) {
+			$this->addError($object, $attribute, $this->message);
 		}
 	}
 
 	/**
+	 * Validates the given value.
+	 * @param mixed $value the value to be validated.
+	 * @return boolean whether the value is valid.
+	 */
+	public function validateValue($value)
+	{
+		return !is_array($value) &&
+			(!$this->not && preg_match($this->pattern, $value)
+			|| $this->not && !preg_match($this->pattern, $value));
+	}
+
+	/**
 	 * Returns the JavaScript needed for performing client-side validation.
 	 * @param \yii\base\Model $object the data object being validated
 	 * @param string $attribute the name of the attribute to be validated.
 	 * @return string the client-side validation script.
-	 * @throws \yii\base\Exception if the "pattern" is not a valid regular expression
+	 * @throws InvalidConfigException if the "pattern" is not a valid regular expression
 	 */
 	public function clientValidateAttribute($object, $attribute)
 	{
-		if ($this->pattern === null) {
-			throw new \yii\base\Exception('The "pattern" property must be specified with a valid regular expression.');
-		}
-
-		$message = ($this->message !== null) ? $this->message : \Yii::t('yii|{attribute} is invalid.');
-		$message = strtr($message, array(
+		$message = strtr($this->message, array(
 			'{attribute}' => $object->getAttributeLabel($attribute),
 			'{value}' => $object->$attribute,
 		));
@@ -88,7 +101,7 @@ class RegularExpressionValidator extends Validator
 		}
 
 		return "
-if (" . ($this->allowEmpty ? "$.trim(value)!='' && " : '') . ($this->not ? '' : '!') . "value.match($pattern)) {
+if (" . ($this->skipOnEmpty ? "$.trim(value)!='' && " : '') . ($this->not ? '' : '!') . "value.match($pattern)) {
 	messages.push(" . json_encode($message) . ");
 }
 ";
diff --git a/framework/validators/RequiredValidator.php b/framework/validators/RequiredValidator.php
index 66b9c3c..3b13eb3 100644
--- a/framework/validators/RequiredValidator.php
+++ b/framework/validators/RequiredValidator.php
@@ -7,6 +7,8 @@
 
 namespace yii\validators;
 
+use Yii;
+
 /**
  * RequiredValidator validates that the specified attribute does not have null or empty value.
  *
@@ -16,6 +18,10 @@ namespace yii\validators;
 class RequiredValidator extends Validator
 {
 	/**
+	 * @var boolean whether to skip this validator if the value being validated is empty.
+	 */
+	public $skipOnEmpty = false;
+	/**
 	 * @var mixed the desired value that the attribute must have.
 	 * If this is null, the validator will validate that the specified attribute is not empty.
 	 * If this is set as a value that is not null, the validator will validate that
@@ -35,6 +41,18 @@ class RequiredValidator extends Validator
 	public $strict = false;
 
 	/**
+	 * Initializes the validator.
+	 */
+	public function init()
+	{
+		parent::init();
+		if ($this->message === null) {
+			$this->message = $this->requiredValue === null ? Yii::t('yii|{attribute} is invalid.')
+				: Yii::t('yii|{attribute} must be "{requiredValue}".');
+		}
+	}
+
+	/**
 	 * Validates the attribute of the object.
 	 * If there is any error, the error message is added to the object.
 	 * @param \yii\base\Model $object the object being validated
@@ -45,13 +63,11 @@ class RequiredValidator extends Validator
 		$value = $object->$attribute;
 		if ($this->requiredValue === null) {
 			if ($this->strict && $value === null || !$this->strict && $this->isEmpty($value, true)) {
-				$message = ($this->message !== null) ? $this->message : \Yii::t('yii|{attribute} cannot be blank.');
-				$this->addError($object, $attribute, $message);
+				$this->addError($object, $attribute, $this->message);
 			}
 		} else {
 			if (!$this->strict && $value != $this->requiredValue || $this->strict && $value !== $this->requiredValue) {
-				$message = ($this->message !== null) ? $this->message : \Yii::t('yii|{attribute} must be "{requiredValue}".');
-				$this->addError($object, $attribute, $message, array(
+				$this->addError($object, $attribute, $this->message, array(
 					'{requiredValue}' => $this->requiredValue,
 				));
 			}
@@ -59,6 +75,23 @@ class RequiredValidator extends Validator
 	}
 
 	/**
+	 * Validates the given value.
+	 * @param mixed $value the value to be validated.
+	 * @return boolean whether the value is valid.
+	 */
+	public function validateValue($value)
+	{
+		if ($this->requiredValue === null) {
+			if ($this->strict && $value !== null || !$this->strict && !$this->isEmpty($value, true)) {
+				return true;
+			}
+		} elseif (!$this->strict && $value == $this->requiredValue || $this->strict && $value === $this->requiredValue) {
+			return true;
+		}
+		return false;
+	}
+
+	/**
 	 * Returns the JavaScript needed for performing client-side validation.
 	 * @param \yii\base\Model $object the data object being validated
 	 * @param string $attribute the name of the attribute to be validated.
@@ -66,12 +99,8 @@ class RequiredValidator extends Validator
 	 */
 	public function clientValidateAttribute($object, $attribute)
 	{
-		$message = $this->message;
 		if ($this->requiredValue !== null) {
-			if ($message === null) {
-				$message = \Yii::t('yii|{attribute} must be "{requiredValue}".');
-			}
-			$message = strtr($message, array(
+			$message = strtr($this->message, array(
 				'{attribute}' => $object->getAttributeLabel($attribute),
 				'{value}' => $object->$attribute,
 				'{requiredValue}' => $this->requiredValue,
@@ -82,10 +111,7 @@ if (value != " . json_encode($this->requiredValue) . ") {
 }
 ";
 		} else {
-			if ($message === null) {
-				$message = \Yii::t('yii|{attribute} cannot be blank.');
-			}
-			$message = strtr($message, array(
+			$message = strtr($this->message, array(
 				'{attribute}' => $object->getAttributeLabel($attribute),
 				'{value}' => $object->$attribute,
 			));
diff --git a/framework/validators/StringValidator.php b/framework/validators/StringValidator.php
index 9135b9e..8b8c73b 100644
--- a/framework/validators/StringValidator.php
+++ b/framework/validators/StringValidator.php
@@ -7,6 +7,8 @@
 
 namespace yii\validators;
 
+use Yii;
+
 /**
  * StringValidator validates that the attribute value is of certain length.
  *
@@ -46,19 +48,34 @@ class StringValidator extends Validator
 	 */
 	public $notEqual;
 	/**
-	 * @var boolean whether the attribute value can be null or empty. Defaults to true,
-	 * meaning that if the attribute is empty, it is considered valid.
+	 * @var string the encoding of the string value to be validated (e.g. 'UTF-8').
+	 * If this property is not set, [[\yii\base\Application::charset]] will be used.
 	 */
-	public $allowEmpty = true;
+	public $encoding;
+
+
 	/**
-	 * @var mixed the encoding of the string value to be validated (e.g. 'UTF-8').
-	 * This property is used only when mbstring PHP extension is enabled.
-	 * The value of this property will be used as the 2nd parameter of the
-	 * mb_strlen() function. If this property is not set, the application charset
-	 * will be used. If this property is set false, then strlen() will be used even
-	 * if mbstring is enabled.
+	 * Initializes the validator.
 	 */
-	public $encoding;
+	public function init()
+	{
+		parent::init();
+		if ($this->encoding === null) {
+			$this->encoding = Yii::$app->charset;
+		}
+		if ($this->message === null) {
+			$this->message = Yii::t('yii|{attribute} must be a string.');
+		}
+		if ($this->min !== null && $this->tooShort === null) {
+			$this->tooShort = Yii::t('yii|{attribute} should contain at least {min} characters.');
+		}
+		if ($this->max !== null && $this->tooLong === null) {
+			$this->tooLong = Yii::t('yii|{attribute} should contain at most {max} characters.');
+		}
+		if ($this->is !== null && $this->notEqual === null) {
+			$this->notEqual = Yii::t('yii|{attribute} should contain {length} characters.');
+		}
+	}
 
 	/**
 	 * Validates the attribute of the object.
@@ -69,34 +86,39 @@ class StringValidator extends Validator
 	public function validateAttribute($object, $attribute)
 	{
 		$value = $object->$attribute;
-		if ($this->allowEmpty && $this->isEmpty($value)) {
-			return;
-		}
 
 		if (!is_string($value)) {
-			$message = ($this->message !== null) ? $this->message : \Yii::t('yii|{attribute} must be a string.');
-			$this->addError($object, $attribute, $message);
+			$this->addError($object, $attribute, $this->message);
 			return;
 		}
 
-		if (function_exists('mb_strlen') && $this->encoding !== false) {
-			$length = mb_strlen($value, $this->encoding ? $this->encoding : \Yii::$app->charset);
-		} else {
-			$length = strlen($value);
-		}
+		$length = mb_strlen($value, $this->encoding);
 
 		if ($this->min !== null && $length < $this->min) {
-			$message = ($this->tooShort !== null) ? $this->tooShort : \Yii::t('yii|{attribute} is too short (minimum is {min} characters).');
-			$this->addError($object, $attribute, $message, array('{min}' => $this->min));
+			$this->addError($object, $attribute, $this->tooShort, array('{min}' => $this->min));
 		}
 		if ($this->max !== null && $length > $this->max) {
-			$message = ($this->tooLong !== null) ? $this->tooLong : \Yii::t('yii|{attribute} is too long (maximum is {max} characters).');
-			$this->addError($object, $attribute, $message, array('{max}' => $this->max));
+			$this->addError($object, $attribute, $this->tooLong, array('{max}' => $this->max));
 		}
 		if ($this->is !== null && $length !== $this->is) {
-			$message = ($this->notEqual !== null) ? $this->notEqual : \Yii::t('yii|{attribute} is of the wrong length (should be {length} characters).');
-			$this->addError($object, $attribute, $message, array('{length}' => $this->is));
+			$this->addError($object, $attribute, $this->notEqual, array('{length}' => $this->is));
+		}
+	}
+
+	/**
+	 * Validates the given value.
+	 * @param mixed $value the value to be validated.
+	 * @return boolean whether the value is valid.
+	 */
+	public function validateValue($value)
+	{
+		if (!is_string($value)) {
+			return false;
 		}
+		$length = mb_strlen($value, $this->encoding);
+		return ($this->min === null || $length >= $this->min)
+			&& ($this->max === null || $length <= $this->max)
+			&& ($this->is === null || $length === $this->is);
 	}
 
 	/**
@@ -110,28 +132,19 @@ class StringValidator extends Validator
 		$label = $object->getAttributeLabel($attribute);
 		$value = $object->$attribute;
 
-		if (($notEqual = $this->notEqual) === null) {
-			$notEqual = \Yii::t('yii|{attribute} is of the wrong length (should be {length} characters).');
-		}
-		$notEqual = strtr($notEqual, array(
+		$notEqual = strtr($this->notEqual, array(
 			'{attribute}' => $label,
 			'{value}' => $value,
 			'{length}' => $this->is,
 		));
 
-		if (($tooShort = $this->tooShort) === null) {
-			$tooShort = \Yii::t('yii|{attribute} is too short (minimum is {min} characters).');
-		}
-		$tooShort = strtr($tooShort, array(
+		$tooShort = strtr($this->tooShort, array(
 			'{attribute}' => $label,
 			'{value}' => $value,
 			'{min}' => $this->min,
 		));
 
-		if (($tooLong = $this->tooLong) === null) {
-			$tooLong = \Yii::t('yii|{attribute} is too long (maximum is {max} characters).');
-		}
-		$tooLong = strtr($tooLong, array(
+		$tooLong = strtr($this->tooLong, array(
 			'{attribute}' => $label,
 			'{value}' => $value,
 			'{max}' => $this->max,
@@ -160,7 +173,7 @@ if(value.length!= {$this->is}) {
 ";
 		}
 
-		if ($this->allowEmpty) {
+		if ($this->skipOnEmpty) {
 			$js = "
 if($.trim(value)!='') {
 	$js
diff --git a/framework/validators/UniqueValidator.php b/framework/validators/UniqueValidator.php
index bc12f5a..fa55df7 100644
--- a/framework/validators/UniqueValidator.php
+++ b/framework/validators/UniqueValidator.php
@@ -6,6 +6,8 @@
  */
 
 namespace yii\validators;
+
+use Yii;
 use yii\base\InvalidConfigException;
 
 /**
@@ -17,11 +19,6 @@ use yii\base\InvalidConfigException;
 class UniqueValidator extends Validator
 {
 	/**
-	 * @var boolean whether the attribute value can be null or empty. Defaults to true,
-	 * meaning that if the attribute is empty, it is considered valid.
-	 */
-	public $allowEmpty = true;
-	/**
 	 * @var string the ActiveRecord class name or alias of the class
 	 * that should be used to look for the attribute value being validated.
 	 * Defaults to null, meaning using the ActiveRecord class of the attribute being validated.
@@ -36,6 +33,17 @@ class UniqueValidator extends Validator
 	public $attributeName;
 
 	/**
+	 * Initializes the validator.
+	 */
+	public function init()
+	{
+		parent::init();
+		if ($this->message === null) {
+			$this->message = Yii::t('yii|{attribute} "{value}" has already been taken.');
+		}
+	}
+
+	/**
 	 * Validates the attribute of the object.
 	 * If there is any error, the error message is added to the object.
 	 * @param \yii\db\ActiveRecord $object the object being validated
@@ -45,7 +53,9 @@ class UniqueValidator extends Validator
 	public function validateAttribute($object, $attribute)
 	{
 		$value = $object->$attribute;
-		if ($this->allowEmpty && $this->isEmpty($value)) {
+
+		if (is_array($value)) {
+			$this->addError($object, $attribute, Yii::t('yii|{attribute} is invalid.'));
 			return;
 		}
 
@@ -55,7 +65,7 @@ class UniqueValidator extends Validator
 
 		$table = $className::getTableSchema();
 		if (($column = $table->getColumn($attributeName)) === null) {
-			throw new InvalidConfigException('Table "' . $table->name . '" does not have a column named "' . $attributeName . '"');
+			throw new InvalidConfigException("Table '{$table->name}' does not have a column named '$attributeName'.");
 		}
 
 		$query = $className::find();
@@ -84,8 +94,7 @@ class UniqueValidator extends Validator
 		}
 
 		if ($exists) {
-			$message = $this->message !== null ? $this->message : \Yii::t('yii|{attribute} "{value}" has already been taken.');
-			$this->addError($object, $attribute, $message);
+			$this->addError($object, $attribute, $this->message);
 		}
 	}
 }
\ No newline at end of file
diff --git a/framework/validators/UrlValidator.php b/framework/validators/UrlValidator.php
index 0ba039b..cd6bfef 100644
--- a/framework/validators/UrlValidator.php
+++ b/framework/validators/UrlValidator.php
@@ -7,6 +7,8 @@
 
 namespace yii\validators;
 
+use Yii;
+
 /**
  * UrlValidator validates that the attribute value is a valid http or https URL.
  *
@@ -32,11 +34,18 @@ class UrlValidator extends Validator
 	 * contain the scheme part.
 	 **/
 	public $defaultScheme;
+
+
 	/**
-	 * @var boolean whether the attribute value can be null or empty. Defaults to true,
-	 * meaning that if the attribute is empty, it is considered valid.
+	 * Initializes the validator.
 	 */
-	public $allowEmpty = true;
+	public function init()
+	{
+		parent::init();
+		if ($this->message === null) {
+			$this->message = Yii::t('yii|{attribute} is not a valid URL.');
+		}
+	}
 
 	/**
 	 * Validates the attribute of the object.
@@ -47,23 +56,19 @@ class UrlValidator extends Validator
 	public function validateAttribute($object, $attribute)
 	{
 		$value = $object->$attribute;
-		if ($this->allowEmpty && $this->isEmpty($value)) {
-			return;
-		}
-		if (($value = $this->validateValue($value)) !== false) {
-			$object->$attribute = $value;
+		if ($this->validateValue($value)) {
+			if ($this->defaultScheme !== null && strpos($value, '://') === false) {
+				$object->$attribute = $this->defaultScheme . '://' . $value;
+			}
 		} else {
-			$message = ($this->message !== null) ? $this->message : \Yii::t('yii|{attribute} is not a valid URL.');
-			$this->addError($object, $attribute, $message);
+			$this->addError($object, $attribute, $this->message);
 		}
 	}
 
 	/**
-	 * Validates a static value to see if it is a valid URL.
-	 * Note that this method does not respect [[allowEmpty]] property.
-	 * This method is provided so that you can call it directly without going through the model validation rule mechanism.
-	 * @param mixed $value the value to be validated
-	 * @return mixed false if the the value is not a valid URL, otherwise the possibly modified value ({@see defaultScheme})
+	 * Validates the given value.
+	 * @param mixed $value the value to be validated.
+	 * @return boolean whether the value is valid.
 	 */
 	public function validateValue($value)
 	{
@@ -80,7 +85,7 @@ class UrlValidator extends Validator
 			}
 
 			if (preg_match($pattern, $value)) {
-				return $value;
+				return true;
 			}
 		}
 		return false;
@@ -95,8 +100,7 @@ class UrlValidator extends Validator
 	 */
 	public function clientValidateAttribute($object, $attribute)
 	{
-		$message = ($this->message !== null) ? $this->message : \Yii::t('yii|{attribute} is not a valid URL.');
-		$message = strtr($message, array(
+		$message = strtr($this->message, array(
 			'{attribute}' => $object->getAttributeLabel($attribute),
 			'{value}' => $object->$attribute,
 		));
@@ -121,7 +125,7 @@ $js
 ";
 		}
 
-		if ($this->allowEmpty) {
+		if ($this->skipOnEmpty) {
 			$js = "
 if($.trim(value)!='') {
 	$js
diff --git a/framework/validators/Validator.php b/framework/validators/Validator.php
index b688f32..5ab8dfe 100644
--- a/framework/validators/Validator.php
+++ b/framework/validators/Validator.php
@@ -7,7 +7,9 @@
 
 namespace yii\validators;
 
+use Yii;
 use yii\base\Component;
+use yii\base\NotSupportedException;
 
 /**
  * Validator is the base class for all validators.
@@ -81,7 +83,7 @@ abstract class Validator extends Component
 	 */
 	public $message;
 	/**
-	 * @var array list of scenarios that the validator should be applied.
+	 * @var array list of scenarios that the validator can be applied to.
 	 */
 	public $on = array();
 	/**
@@ -94,6 +96,12 @@ abstract class Validator extends Component
 	 */
 	public $skipOnError = true;
 	/**
+	 * @var boolean whether this validation rule should be skipped if the attribute value
+	 * is null or an empty string.
+	 */
+	public $skipOnEmpty = true;
+
+	/**
 	 * @var boolean whether to enable client-side validation. Defaults to null, meaning
 	 * its actual value inherits from that of [[\yii\web\ActiveForm::enableClientValidation]].
 	 */
@@ -149,7 +157,7 @@ abstract class Validator extends Component
 			}
 		}
 
-		return \Yii::createObject($params);
+		return Yii::createObject($params);
 	}
 
 	/**
@@ -168,13 +176,26 @@ abstract class Validator extends Component
 			$attributes = $this->attributes;
 		}
 		foreach ($attributes as $attribute) {
-			if (!($this->skipOnError && $object->hasErrors($attribute))) {
+			$skip = $this->skipOnError && $object->hasErrors($attribute)
+				 || $this->skipOnEmpty && $this->isEmpty($object->$attribute);
+			if (!$skip) {
 				$this->validateAttribute($object, $attribute);
 			}
 		}
 	}
 
 	/**
+	 * Validates a value.
+	 * A validator class can implement this method to support data validation out of the context of a data model.
+	 * @param mixed $value the data value to be validated.
+	 * @throws NotSupportedException if data validation without a model is not supported
+	 */
+	public function validateValue($value)
+	{
+		throw new NotSupportedException(get_class($this) . ' does not support validateValue().');
+	}
+
+	/**
 	 * Returns the JavaScript needed for performing client-side validation.
 	 *
 	 * You may override this method to return the JavaScript validation code if
@@ -224,8 +245,9 @@ abstract class Validator extends Component
 	 */
 	public function addError($object, $attribute, $message, $params = array())
 	{
+		$value = $object->$attribute;
 		$params['{attribute}'] = $object->getAttributeLabel($attribute);
-		$params['{value}'] = $object->$attribute;
+		$params['{value}'] = is_array($value) ? 'array()' : $value;
 		$object->addError($attribute, strtr($message, $params));
 	}
 
diff --git a/framework/web/Application.php b/framework/web/Application.php
index b839d92..f9b615d 100644
--- a/framework/web/Application.php
+++ b/framework/web/Application.php
@@ -23,21 +23,15 @@ class Application extends \yii\base\Application
 	public $defaultRoute = 'site';
 
 	/**
-	 * Sets default path aliases.
-	 */
-	public function registerDefaultAliases()
-	{
-		parent::registerDefaultAliases();
-		Yii::$aliases['@webroot'] = dirname($_SERVER['SCRIPT_FILENAME']);
-	}
-
-	/**
 	 * Processes the request.
 	 * @return integer the exit status of the controller action (0 means normal, non-zero values mean abnormal)
 	 */
 	public function processRequest()
 	{
-		list ($route, $params) = $this->getRequest()->resolve();
+		$request = $this->getRequest();
+		Yii::setAlias('@wwwroot', dirname($request->getScriptFile()));
+		Yii::setAlias('@www', $request->getBaseUrl());
+		list ($route, $params) = $request->resolve();
 		return $this->runAction($route, $params);
 	}
 
diff --git a/framework/web/Request.php b/framework/web/Request.php
index 093a394..369fa0c 100644
--- a/framework/web/Request.php
+++ b/framework/web/Request.php
@@ -43,8 +43,6 @@ class Request extends \yii\base\Request
 	 */
 	public function resolve()
 	{
-		Yii::setAlias('@www', $this->getBaseUrl());
-
 		$result = Yii::$app->getUrlManager()->parseRequest($this);
 		if ($result !== false) {
 			list ($route, $params) = $result;
@@ -301,7 +299,8 @@ class Request extends \yii\base\Request
 	public function getScriptUrl()
 	{
 		if ($this->_scriptUrl === null) {
-			$scriptName = basename($_SERVER['SCRIPT_FILENAME']);
+			$scriptFile = $this->getScriptFile();
+			$scriptName = basename($scriptFile);
 			if (basename($_SERVER['SCRIPT_NAME']) === $scriptName) {
 				$this->_scriptUrl = $_SERVER['SCRIPT_NAME'];
 			} elseif (basename($_SERVER['PHP_SELF']) === $scriptName) {
@@ -310,8 +309,8 @@ class Request extends \yii\base\Request
 				$this->_scriptUrl = $_SERVER['ORIG_SCRIPT_NAME'];
 			} elseif (($pos = strpos($_SERVER['PHP_SELF'], '/' . $scriptName)) !== false) {
 				$this->_scriptUrl = substr($_SERVER['SCRIPT_NAME'], 0, $pos) . '/' . $scriptName;
-			} elseif (isset($_SERVER['DOCUMENT_ROOT']) && strpos($_SERVER['SCRIPT_FILENAME'], $_SERVER['DOCUMENT_ROOT']) === 0) {
-				$this->_scriptUrl = str_replace('\\', '/', str_replace($_SERVER['DOCUMENT_ROOT'], '', $_SERVER['SCRIPT_FILENAME']));
+			} elseif (isset($_SERVER['DOCUMENT_ROOT']) && strpos($scriptFile, $_SERVER['DOCUMENT_ROOT']) === 0) {
+				$this->_scriptUrl = str_replace('\\', '/', str_replace($_SERVER['DOCUMENT_ROOT'], '', $scriptFile));
 			} else {
 				throw new InvalidConfigException('Unable to determine the entry script URL.');
 			}
@@ -330,6 +329,30 @@ class Request extends \yii\base\Request
 		$this->_scriptUrl = '/' . trim($value, '/');
 	}
 
+	private $_scriptFile;
+
+	/**
+	 * Returns the entry script file path.
+	 * The default implementation will simply return `$_SERVER['SCRIPT_FILENAME']`.
+	 * @return string the entry script file path
+	 */
+	public function getScriptFile()
+	{
+		return isset($this->_scriptFile) ? $this->_scriptFile : $_SERVER['SCRIPT_FILENAME'];
+	}
+
+	/**
+	 * Sets the entry script file path.
+	 * The entry script file path normally can be obtained from `$_SERVER['SCRIPT_FILENAME']`.
+	 * If your server configuration does not return the correct value, you may configure
+	 * this property to make it right.
+	 * @param string $value the entry script file path.
+	 */
+	public function setScriptFile($value)
+	{
+		$this->_scriptFile = $value;
+	}
+
 	private $_pathInfo;
 
 	/**
diff --git a/framework/web/UploadedFile.php b/framework/web/UploadedFile.php
new file mode 100644
index 0000000..c67281c
--- /dev/null
+++ b/framework/web/UploadedFile.php
@@ -0,0 +1,246 @@
+<?php
+/**
+ * @link http://www.yiiframework.com/
+ * @copyright Copyright (c) 2008 Yii Software LLC
+ * @license http://www.yiiframework.com/license/
+ */
+
+namespace yii\web;
+
+use yii\widgets\ActiveForm;
+
+/**
+ * @author Qiang Xue <qiang.xue@gmail.com>
+ * @since 2.0
+ */
+class UploadedFile extends \yii\base\Object
+{
+	private static $_files;
+	private $_name;
+	private $_tempName;
+	private $_type;
+	private $_size;
+	private $_error;
+
+
+	/**
+	 * Constructor.
+	 * Instead of using the constructor to create a new instance,
+	 * you should normally call [[getInstance()]] or [[getInstances()]]
+	 * to obtain new instances.
+	 * @param string $name the original name of the file being uploaded
+	 * @param string $tempName the path of the uploaded file on the server.
+	 * @param string $type the MIME-type of the uploaded file (such as "image/gif").
+	 * @param integer $size the actual size of the uploaded file in bytes
+	 * @param integer $error the error code
+	 */
+	public function __construct($name, $tempName, $type, $size, $error)
+	{
+		$this->_name = $name;
+		$this->_tempName = $tempName;
+		$this->_type = $type;
+		$this->_size = $size;
+		$this->_error = $error;
+	}
+
+	/**
+	 * String output.
+	 * This is PHP magic method that returns string representation of an object.
+	 * The implementation here returns the uploaded file's name.
+	 * @return string the string representation of the object
+	 */
+	public function __toString()
+	{
+		return $this->_name;
+	}
+
+	/**
+	 * Returns an uploaded file for the given model attribute.
+	 * The file should be uploaded using [[ActiveForm::fileInput()]].
+	 * @param \yii\base\Model $model the data model
+	 * @param string $attribute the attribute name. The attribute name may contain array indexes.
+	 * For example, '[1]file' for tabular file uploading; and 'file[1]' for an element in a file array.
+	 * @return UploadedFile the instance of the uploaded file.
+	 * Null is returned if no file is uploaded for the specified model attribute.
+	 * @see getInstanceByName
+	 */
+	public static function getInstance($model, $attribute)
+	{
+		$name = ActiveForm::getInputName($model, $attribute);
+		return static::getInstanceByName($name);
+	}
+
+	/**
+	 * Returns all uploaded files for the given model attribute.
+	 * @param \yii\base\Model $model the data model
+	 * @param string $attribute the attribute name. The attribute name may contain array indexes
+	 * for tabular file uploading, e.g. '[1]file'.
+	 * @return UploadedFile[] array of UploadedFile objects.
+	 * Empty array is returned if no available file was found for the given attribute.
+	 */
+	public static function getInstances($model, $attribute)
+	{
+		$name = ActiveForm::getInputName($model, $attribute);
+		return static::getInstancesByName($name);
+	}
+
+	/**
+	 * Returns an uploaded file according to the given file input name.
+	 * The name can be a plain string or a string like an array element (e.g. 'Post[imageFile]', or 'Post[0][imageFile]').
+	 * @param string $name the name of the file input field.
+	 * @return UploadedFile the instance of the uploaded file.
+	 * Null is returned if no file is uploaded for the specified name.
+	 */
+	public static function getInstanceByName($name)
+	{
+		$files = static::loadFiles();
+		return isset($files[$name]) ? $files[$name] : null;
+	}
+
+	/**
+	 * Returns an array of uploaded files corresponding to the specified file input name.
+	 * This is mainly used when multiple files were uploaded and saved as 'files[0]', 'files[1]',
+	 * 'files[n]'..., and you can retrieve them all by passing 'files' as the name.
+	 * @param string $name the name of the array of files
+	 * @return UploadedFile[] the array of CUploadedFile objects. Empty array is returned
+	 * if no adequate upload was found. Please note that this array will contain
+	 * all files from all sub-arrays regardless how deeply nested they are.
+	 */
+	public static function getInstancesByName($name)
+	{
+		$files = static::loadFiles();
+		if (isset($files[$name])) {
+			return array($files[$name]);
+		}
+		$results = array();
+		foreach ($files as $key => $file) {
+			if (strpos($key, "{$name}[") === 0) {
+				$results[] = self::$_files[$key];
+			}
+		}
+		return $results;
+	}
+
+	/**
+	 * Cleans up the loaded UploadedFile instances.
+	 * This method is mainly used by test scripts to set up a fixture.
+	 */
+	public static function reset()
+	{
+		self::$_files = null;
+	}
+
+	/**
+	 * Saves the uploaded file.
+	 * Note that this method uses php's move_uploaded_file() method. If the target file `$file`
+	 * already exists, it will be overwritten.
+	 * @param string $file the file path used to save the uploaded file
+	 * @param boolean $deleteTempFile whether to delete the temporary file after saving.
+	 * If true, you will not be able to save the uploaded file again in the current request.
+	 * @return boolean true whether the file is saved successfully
+	 * @see error
+	 */
+	public function saveAs($file, $deleteTempFile = true)
+	{
+		if ($this->_error == UPLOAD_ERR_OK) {
+			if ($deleteTempFile) {
+				return move_uploaded_file($this->_tempName, $file);
+			} elseif (is_uploaded_file($this->_tempName)) {
+				return copy($this->_tempName, $file);
+			}
+		}
+		return false;
+	}
+
+	/**
+	 * @return string the original name of the file being uploaded
+	 */
+	public function getName()
+	{
+		return $this->_name;
+	}
+
+	/**
+	 * @return string the path of the uploaded file on the server.
+	 * Note, this is a temporary file which will be automatically deleted by PHP
+	 * after the current request is processed.
+	 */
+	public function getTempName()
+	{
+		return $this->_tempName;
+	}
+
+	/**
+	 * @return string the MIME-type of the uploaded file (such as "image/gif").
+	 * Since this MIME type is not checked on the server side, do not take this value for granted.
+	 * Instead, use [[FileHelper::getMimeType()]] to determine the exact MIME type.
+	 */
+	public function getType()
+	{
+		return $this->_type;
+	}
+
+	/**
+	 * @return integer the actual size of the uploaded file in bytes
+	 */
+	public function getSize()
+	{
+		return $this->_size;
+	}
+
+	/**
+	 * Returns an error code describing the status of this file uploading.
+	 * @return integer the error code
+	 * @see http://www.php.net/manual/en/features.file-upload.errors.php
+	 */
+	public function getError()
+	{
+		return $this->_error;
+	}
+
+	/**
+	 * @return boolean whether there is an error with the uploaded file.
+	 * Check [[error]] for detailed error code information.
+	 */
+	public function getHasError()
+	{
+		return $this->_error != UPLOAD_ERR_OK;
+	}
+
+	/**
+	 * Creates UploadedFile instances from $_FILE.
+	 * @return array the UploadedFile instances
+	 */
+	private static function loadFiles()
+	{
+		if (self::$_files === null) {
+			self::$_files = array();
+			if (isset($_FILES) && is_array($_FILES)) {
+				foreach ($_FILES as $class => $info) {
+					self::loadFilesRecursive($class, $info['name'], $info['tmp_name'], $info['type'], $info['size'], $info['error']);
+				}
+			}
+		}
+		return self::$_files;
+	}
+
+	/**
+	 * Creates UploadedFile instances from $_FILE recursively.
+	 * @param string $key key for identifying uploaded file: class name and sub-array indexes
+	 * @param mixed $names file names provided by PHP
+	 * @param mixed $tempNames temporary file names provided by PHP
+	 * @param mixed $types file types provided by PHP
+	 * @param mixed $sizes file sizes provided by PHP
+	 * @param mixed $errors uploading issues provided by PHP
+	 */
+	private static function loadFilesRecursive($key, $names, $tempNames, $types, $sizes, $errors)
+	{
+		if (is_array($names)) {
+			foreach ($names as $i => $name) {
+				self::loadFilesRecursive($key . '[' . $i . ']', $name, $tempNames[$i], $types[$i], $sizes[$i], $errors[$i]);
+			}
+		} else {
+			self::$_files[$key] = new self($names, $tempNames, $types, $sizes, $errors);
+		}
+	}
+}
diff --git a/framework/widgets/ActiveForm.php b/framework/widgets/ActiveForm.php
index 8ac5365..48bc181 100644
--- a/framework/widgets/ActiveForm.php
+++ b/framework/widgets/ActiveForm.php
@@ -52,10 +52,6 @@ class ActiveForm extends Widget
 	public $enableClientValidation = false;
 
 	public $options = array();
-	/**
-	 * @var array model-class mapped to name prefix
-	 */
-	public $modelMap;
 
 	/**
 	 * @param Model|Model[] $models
@@ -240,35 +236,6 @@ class ActiveForm extends Widget
 		return Html::radioList($name, $checked, $items, $options);
 	}
 
-	public function getInputName($model, $attribute)
-	{
-		$class = get_class($model);
-		if (isset($this->modelMap[$class])) {
-			$class = $this->modelMap[$class];
-		} elseif (($pos = strrpos($class, '\\')) !== false) {
-			$class = substr($class, $pos + 1);
-		}
-		if (!preg_match('/(^|.*\])(\w+)(\[.*|$)/', $attribute, $matches)) {
-			throw new InvalidParamException('Attribute name must contain word characters only.');
-		}
-		$prefix = $matches[1];
-		$attribute = $matches[2];
-		$suffix = $matches[3];
-		if ($class === '' && $prefix === '') {
-			return $attribute . $suffix;
-		} elseif ($class !== '') {
-			return $class . $prefix . "[$attribute]" . $suffix;
-		} else {
-			throw new InvalidParamException('Model name cannot be mapped to empty for tabular inputs.');
-		}
-	}
-
-	public function getInputId($model, $attribute)
-	{
-		$name = $this->getInputName($model, $attribute);
-		return str_replace(array('[]', '][', '[', ']', ' '), array('', '-', '-', '', '-'), $name);
-	}
-
 	public function getAttributeValue($model, $attribute)
 	{
 		if (!preg_match('/(^|.*\])(\w+)(\[.*|$)/', $attribute, $matches)) {
@@ -299,4 +266,34 @@ class ActiveForm extends Widget
 			throw new InvalidParamException('Attribute name must contain word characters only.');
 		}
 	}
+
+	/**
+	 * @param Model $model
+	 * @param string $attribute
+	 * @return string
+	 * @throws \yii\base\InvalidParamException
+	 */
+	public static function getInputName($model, $attribute)
+	{
+		$formName = $model->formName();
+		if (!preg_match('/(^|.*\])(\w+)(\[.*|$)/', $attribute, $matches)) {
+			throw new InvalidParamException('Attribute name must contain word characters only.');
+		}
+		$prefix = $matches[1];
+		$attribute = $matches[2];
+		$suffix = $matches[3];
+		if ($formName === '' && $prefix === '') {
+			return $attribute . $suffix;
+		} elseif ($formName !== '') {
+			return $formName . $prefix . "[$attribute]" . $suffix;
+		} else {
+			throw new InvalidParamException(get_class($model) . '::formName() cannot be empty for tabular inputs.');
+		}
+	}
+
+	public static function getInputId($model, $attribute)
+	{
+		$name = static::getInputName($model, $attribute);
+		return str_replace(array('[]', '][', '[', ']', ' '), array('', '-', '-', '', '-'), $name);
+	}
 }
diff --git a/tests/unit/framework/base/ComponentTest.php b/tests/unit/framework/base/ComponentTest.php
index 97b0116..74b6e9a 100644
--- a/tests/unit/framework/base/ComponentTest.php
+++ b/tests/unit/framework/base/ComponentTest.php
@@ -41,12 +41,12 @@ class ComponentTest extends TestCase
 		$component->attachBehavior('a', $behavior);
 		$this->assertSame($behavior, $component->getBehavior('a'));
 		$component->on('test', 'fake');
-		$this->assertEquals(1, $component->getEventHandlers('test')->count);
+		$this->assertTrue($component->hasEventHandlers('test'));
 
 		$clone = clone $component;
 		$this->assertNotSame($component, $clone);
 		$this->assertNull($clone->getBehavior('a'));
-		$this->assertEquals(0, $clone->getEventHandlers('test')->count);
+		$this->assertFalse($clone->hasEventHandlers('test'));
 	}
 	
 	public function testHasProperty()
@@ -151,34 +151,32 @@ class ComponentTest extends TestCase
 
 	public function testOn()
 	{
-		$this->assertEquals(0, $this->component->getEventHandlers('click')->getCount());
+		$this->assertFalse($this->component->hasEventHandlers('click'));
 		$this->component->on('click', 'foo');
-		$this->assertEquals(1, $this->component->getEventHandlers('click')->getCount());
-		$this->component->on('click', 'bar');
-		$this->assertEquals(2, $this->component->getEventHandlers('click')->getCount());
-		$p = 'on click';
-		$this->component->$p = 'foo2';
-		$this->assertEquals(3, $this->component->getEventHandlers('click')->getCount());
+		$this->assertTrue($this->component->hasEventHandlers('click'));
 
-		$this->component->getEventHandlers('click')->add('test');
-		$this->assertEquals(4, $this->component->getEventHandlers('click')->getCount());
+		$this->assertFalse($this->component->hasEventHandlers('click2'));
+		$p = 'on click2';
+		$this->component->$p = 'foo2';
+		$this->assertTrue($this->component->hasEventHandlers('click2'));
 	}
 
 	public function testOff()
 	{
+		$this->assertFalse($this->component->hasEventHandlers('click'));
 		$this->component->on('click', 'foo');
-		$this->component->on('click', array($this->component, 'myEventHandler'));
-		$this->assertEquals(2, $this->component->getEventHandlers('click')->getCount());
-
-		$result = $this->component->off('click', 'foo');
-		$this->assertTrue($result);
-		$this->assertEquals(1, $this->component->getEventHandlers('click')->getCount());
-		$result = $this->component->off('click', 'foo');
-		$this->assertFalse($result);
-		$this->assertEquals(1, $this->component->getEventHandlers('click')->getCount());
-		$result = $this->component->off('click', array($this->component, 'myEventHandler'));
-		$this->assertTrue($result);
-		$this->assertEquals(0, $this->component->getEventHandlers('click')->getCount());
+		$this->assertTrue($this->component->hasEventHandlers('click'));
+		$this->component->off('click', 'foo');
+		$this->assertFalse($this->component->hasEventHandlers('click'));
+
+		$this->component->on('click2', 'foo');
+		$this->component->on('click2', 'foo2');
+		$this->component->on('click2', 'foo3');
+		$this->assertTrue($this->component->hasEventHandlers('click2'));
+		$this->component->off('click2', 'foo3');
+		$this->assertTrue($this->component->hasEventHandlers('click2'));
+		$this->component->off('click2');
+		$this->assertFalse($this->component->hasEventHandlers('click2'));
 	}
 
 	public function testTrigger()
diff --git a/tests/unit/framework/helpers/HtmlTest.php b/tests/unit/framework/helpers/HtmlTest.php
index 2c3de72..bf0ca0a 100644
--- a/tests/unit/framework/helpers/HtmlTest.php
+++ b/tests/unit/framework/helpers/HtmlTest.php
@@ -10,7 +10,9 @@ class HtmlTest extends \yii\test\TestCase
 {
 	public function setUp()
 	{
-		new Application('test', '@yiiunit/runtime', array(
+		new Application(array(
+			'id' => 'test',
+			'basePath' => '@yiiunit/runtime',
 			'components' => array(
 				'request' => array(
 					'class' => 'yii\web\Request',