(Yaf >=1.0.0)
Examples:
Plugin example
<?php
   /* bootstrap class should be defined under ./application/Bootstrap.php */
   class Bootstrap extends Yaf_Bootstrap_Abstract {
        public function _initPlugin(Yaf_Dispatcher $dispatcher) {
            /* register a plugin */
            $dispatcher->registerPlugin(new TestPlugin());
        }
   }

   /* plugin class should be placed under ./application/plugins/ */
   class TestPlugin extends Yaf_Plugin_Abstract {
        public function routerStartup(Yaf_Request_Abstract $request, Yaf_Response_Abstract $response) {
            /* before router 
               in this hook,  user can do some url rewrite */
            var_dump("routerStartup");
        }
        public function routerShutdown(Yaf_Request_Abstract $request, Yaf_Response_Abstract $response) {
            /* router complete 
               in this hook, user can do login check */
            var_dump("routerShutdown");
        }
        public function dispatchLoopStartup(Yaf_Request_Abstract $request, Yaf_Response_Abstract $response) {
            var_dump("dispatchLoopStartup");
        }
        public function preDispatch(Yaf_Request_Abstract $request, Yaf_Response_Abstract $response) {
            var_dump("preDispatch");
        }
        public function postDispatch(Yaf_Request_Abstract $request, Yaf_Response_Abstract $response) {
            var_dump("postDispatch");
        }
        public function dispatchLoopShutdown(Yaf_Request_Abstract $request, Yaf_Response_Abstract $response) {
            /* final hoook
               in this hook user can do loging or implement layout */
            var_dump("dispatchLoopShutdown");
        }
   }

   Class IndexController extends Yaf_Controller_Abstract {
        public function indexAction() {
            return FALSE; //prevent rendering
        }
   }

   $config = array(
       "application" => array(
           "directory" => dirname(__FILE__) . "/application/",
       ),
   );
 
   $app = new Yaf_Application($config);
   $app->bootstrap()->run();
?>

The above example will output something similar to:

string(13) "routerStartup"
string(14) "routerShutdown"
string(19) "dispatchLoopStartup"
string(11) "preDispatch"
string(12) "postDispatch"
string(20) "dispatchLoopShutdown"
Yaf_Plugin_Abstract::dispatchLoopStartup

(Yaf >=1.0.0) The dispatchLoopStartup purpose

2016-02-24 16:07:35
Yaf_Plugin_Abstract::preResponse

(Yaf >=1.0.0) The preResponse purpose public

2016-02-24 16:07:36
Yaf_Plugin_Abstract::dispatchLoopShutdown

(Yaf >=1.0.0) The dispatchLoopShutdown purpose

2016-02-24 16:07:35
Yaf_Plugin_Abstract::routerShutdown

(Yaf >=1.0.0) The routerShutdown purpose public

2016-02-24 16:07:36
Yaf_Plugin_Abstract::postDispatch

(Yaf >=1.0.0) The postDispatch purpose public

2016-02-24 16:07:35
Yaf_Plugin_Abstract::routerStartup

(Yaf >=1.0.0) RouterStartup hook public void

2016-02-24 16:07:36
Yaf_Plugin_Abstract::preDispatch

(Yaf >=1.0.0) The preDispatch purpose public

2016-02-24 16:07:36