The HttpKernel component has many interesting features, but the one we need

right now is the *controller resolver*. A controller resolver knows how to

determine the controller to execute and the arguments to pass to it, based on

a Request object. All controller resolvers implement the following interface::

The HttpKernel component has many interesting features, but the ones we need

right now are the *controller resolver* and *argument resolver*. A controller resolver knows how to

determine the controller to execute and the argument resolver determines the arguments to pass to it,

based on a Request object. All controller resolvers implement the following interface

..caution::

The `getArguments()` method in the:class:`Symfony\\Component\\Httpkernel\\Controller\\ControllerResolver`

and respective interface:class:`Symfony\\Component\\Httpkernel\\Controller\\ControllerResolverInterface`

are deprecated as of 3.1 and will be removed in 4.0. You can use the

:class:`Symfony\\Component\\Httpkernel\\Controller\\ArgumentResolver` which uses the

:class:`Symfony\\Component\\Httpkernel\\Controller\\ArgumentResolverInterface` instead.::

namespace Symfony\Component\HttpKernel\Controller;

function getArguments(Request $request, $controller);

}

// ...

interface ArgumentResolverInterface

{

function getArguments(Request $request, $controller);

}

The ``getController()`` method relies on the same convention as the one we

have defined earlier: the ``_controller`` request attribute must contain the

controller associated with the Request. Besides the built-in PHP callbacks,

..note::

With the great flexibility of the default controller resolver, you might

wonder why someone would want to create another one (why would there be an

interface if not?). Two examples: in Symfony, ``getController()`` is

enhanced to support

:doc:`controllers as services</cookbook/controller/service>`; and in

`FrameworkExtraBundle`_, ``getArguments()`` is enhanced to support

parameter converters, where request attributes are converted to objects

automatically.

With the great flexibility of the default controller resolver and argument

resolver, you might wonder why someone would want to create another one

(why would there be an interface if not?). Two examples: in Symfony,

``getController()`` is enhanced to support:doc:`controllers as services</cookbook/controller/service>`;

and ``getArguments()`` provides an extension point to alter or enhance

the resolving of arguments.

Let's conclude with the new version of our framework::

Think about it once more: our framework is more robust and more flexible than

ever and it still has less than40 lines of code.

ever and it still has less than60 lines of code.

.. _`reflection`:http://php.net/reflection

.. _`FrameworkExtraBundle`:http://symfony.com/doc/current/bundles/SensioFrameworkExtraBundle/annotations/converters.html