diff --git a/DependencyInjection/NelmioApiDocExtension.php b/DependencyInjection/NelmioApiDocExtension.php
index 6298f78..ce10263 100644
--- a/DependencyInjection/NelmioApiDocExtension.php
+++ b/DependencyInjection/NelmioApiDocExtension.php
@@ -16,7 +16,6 @@ use Symfony\Component\DependencyInjection\Loader\XmlFileLoader;
 use Symfony\Component\DependencyInjection\ContainerBuilder;
 use Symfony\Component\Config\Definition\Processor;
 use Symfony\Component\Config\FileLocator;
-use Symfony\Component\DependencyInjection\Reference;
 
 class NelmioApiDocExtension extends Extension
 {
diff --git a/Extractor/Handler/FosRestHandler.php b/Extractor/Handler/FosRestHandler.php
index 8ad2602..a3b3373 100644
--- a/Extractor/Handler/FosRestHandler.php
+++ b/Extractor/Handler/FosRestHandler.php
@@ -14,23 +14,22 @@ namespace Nelmio\ApiDocBundle\Extractor\Handler;
 use Nelmio\ApiDocBundle\Extractor\HandlerInterface;
 use Nelmio\ApiDocBundle\Annotation\ApiDoc;
 use Symfony\Component\Routing\Route;
+use FOS\RestBundle\Controller\Annotations\RequestParam;
+use FOS\RestBundle\Controller\Annotations\QueryParam;
 
 class FosRestHandler implements HandlerInterface
 {
-    const FOS_REST_REQUEST_PARAM_CLASS    = 'FOS\\RestBundle\\Controller\\Annotations\\RequestParam';
-    const FOS_REST_QUERY_PARAM_CLASS      = 'FOS\\RestBundle\\Controller\\Annotations\\QueryParam';
-
     public function handle(ApiDoc $annotation, $annotations, Route $route, \ReflectionMethod $method)
     {
         foreach ($annotations as $annot) {
-            if (is_a($annot, self::FOS_REST_REQUEST_PARAM_CLASS)) {
+            if ($annot instanceof RequestParam) {
                 $annotation->addParameter($annot->name, array(
                     'required'    => $annot->strict && $annot->default === null,
                     'dataType'    => $annot->requirements,
                     'description' => $annot->description,
                     'readonly'    => false
                 ));
-            } elseif (is_a($annot, self::FOS_REST_QUERY_PARAM_CLASS)) {
+            } elseif ($annot instanceof QueryParam) {
                 if ($annot->strict && $annot->default === null) {
                     $annotation->addRequirement($annot->name, array(
                         'requirement'   => $annot->requirements,
diff --git a/Extractor/Handler/JmsSecurityExtraHandler.php b/Extractor/Handler/JmsSecurityExtraHandler.php
index 6dfca7a..2c639b4 100644
--- a/Extractor/Handler/JmsSecurityExtraHandler.php
+++ b/Extractor/Handler/JmsSecurityExtraHandler.php
@@ -14,15 +14,14 @@ namespace Nelmio\ApiDocBundle\Extractor\Handler;
 use Nelmio\ApiDocBundle\Extractor\HandlerInterface;
 use Nelmio\ApiDocBundle\Annotation\ApiDoc;
 use Symfony\Component\Routing\Route;
+use JMS\SecurityExtraBundle\Annotation\Secure;
 
 class JmsSecurityExtraHandler implements HandlerInterface
 {
-    const JMS_SECURITY_EXTRA_SECURE_CLASS = 'JMS\\SecurityExtraBundle\\Annotation\\Secure';
-
     public function handle(ApiDoc $annotation, $annotations, Route $route, \ReflectionMethod $method)
     {
         foreach ($annotations as $annot) {
-            if (is_a($annot, self::JMS_SECURITY_EXTRA_SECURE_CLASS)) {
+            if ($annot instanceof Secure) {
                 $annotation->setAuthentication(true);
             }
         }
diff --git a/Extractor/Handler/SensioFrameworkExtraHandler.php b/Extractor/Handler/SensioFrameworkExtraHandler.php
index e92f143..55eac5c 100644
--- a/Extractor/Handler/SensioFrameworkExtraHandler.php
+++ b/Extractor/Handler/SensioFrameworkExtraHandler.php
@@ -14,15 +14,14 @@ namespace Nelmio\ApiDocBundle\Extractor\Handler;
 use Nelmio\ApiDocBundle\Extractor\HandlerInterface;
 use Nelmio\ApiDocBundle\Annotation\ApiDoc;
 use Symfony\Component\Routing\Route;
+use Sensio\Bundle\FrameworkExtraBundle\Configuration\Cache;
 
 class SensioFrameworkExtraHandler implements HandlerInterface
 {
-    const CACHE_ANNOTATION_CLASS = 'Sensio\\Bundle\\FrameworkExtraBundle\\Configuration\\Cache';
-
     public function handle(ApiDoc $annotation, $annotations, Route $route, \ReflectionMethod $method)
     {
         foreach ($annotations as $annot) {
-            if (is_a($annot, self::CACHE_ANNOTATION_CLASS)) {
+            if ($annot instanceof Cache) {
                 $annotation->setCache($annot->getMaxAge());
             }
         }
diff --git a/Extractor/HandlerInterface.php b/Extractor/HandlerInterface.php
index 00557e1..ae2f475 100644
--- a/Extractor/HandlerInterface.php
+++ b/Extractor/HandlerInterface.php
@@ -17,5 +17,13 @@ use Symfony\Component\Routing\Route;
 
 interface HandlerInterface
 {
+    /**
+     * Parse route parameters in order to populate ApiDoc.
+     *
+     * @param Nelmio\ApiDocBundle\Annotation\ApiDoc $annotation
+     * @param array                                 $annotations
+     * @param Symfony\Component\Routing\Route       $route
+     * @param ReflectionMethod                      $method
+     */
     public function handle(ApiDoc $annotation, $annotations, Route $route, \ReflectionMethod $method);
 }
diff --git a/README.md b/README.md
index a146aa2..13ba96e 100644
--- a/README.md
+++ b/README.md
@@ -238,7 +238,9 @@ You can also define your own motd content (above methods list). All you have to
 
 ## Using your own annotations ##
 
-If you have developped your own project-related annotations, and you want to parse them to populate the ApiDoc, you can provide custom handlers as services. You juste have to implements the `Nelmio\ApiDocBundle\Extractor\HandlerInterface` and tag it as `nelmio_api_doc.extractor.handler`.
+If you have developped your own project-related annotations, and you want to parse them to populate the ApiDoc,
+you can provide custom handlers as services. You juste have to implements the
+`Nelmio\ApiDocBundle\Extractor\HandlerInterface` and tag it as `nelmio_api_doc.extractor.handler`.
 
     #app/config/config.yml
     services: