diff --git a/Build/phpstan.neon b/Build/phpstan.neon
index 298c80c12..cc37a8087 100644
--- a/Build/phpstan.neon
+++ b/Build/phpstan.neon
@@ -1,7 +1,6 @@
 parameters:
     ignoreErrors:
             - '#Call to an undefined method Kitodo\\Dlf\\Domain\\Model\\Document::getCurrentDocument\(\)\.#'
-            - '#Parameter \#1 \$documentId of method Kitodo\\Dlf\\Controller\\AbstractController::loadDocument\(\) expects int, array given\.#'
     level: 5
     paths:
         - ../Classes/
diff --git a/Classes/Controller/SruController.php b/Classes/Controller/SruController.php
index 06317a058..a0dba70cc 100644
--- a/Classes/Controller/SruController.php
+++ b/Classes/Controller/SruController.php
@@ -2,10 +2,8 @@
 
 namespace Slub\Dfgviewer\Controller;
 
-use Kitodo\Dlf\Domain\Model\Document;
 use Kitodo\Dlf\Common\MetsDocument;
-use Kitodo\Dlf\Domain\Repository\StructureRepository;
-use TYPO3\CMS\Core\Database\ConnectionPool;
+use TYPO3\CMS\Core\Page\PageRenderer;
 use TYPO3\CMS\Core\Utility\GeneralUtility;
 
 /**
@@ -14,22 +12,27 @@
  * Checks if the METS document contains a link to an SRU endpoint, and if so,
  * adds a search form to the pageview.
  *
- * @package    TYPO3
- * @subpackage    tx_dfgviewer
- * @access    public
+ * @package TYPO3
+ * @subpackage tx_dfgviewer
+ * @access public
  */
 class SruController extends \Kitodo\Dlf\Controller\AbstractController
 {
+    /**
+     * The main method of the controller
+     *
+     * @return void
+     */
     public function mainAction()
     {
         // Load current document.
-        $this->loadDocument($this->requestData);
+        $this->loadDocument();
         if (
             $this->isDocMissing()
             || !$this->document->getCurrentDocument() instanceof MetsDocument
         ) {
             // Quit without doing anything if required variables are not set.
-            return '';
+            return;
         }
 
         // Get digital provenance information.
@@ -45,8 +48,8 @@ public function mainAction()
         }
 
         if (empty($sruLink)) {
-            // Quit without doing anything if required variables are not set.
-            return '';
+            // Quit without doing anything if link is not set.
+            return;
         }
 
         $actionUrl = $this->uriBuilder->reset()
@@ -81,7 +84,7 @@ protected function addSruResultsJS()
             }
             $javascriptFooter .= '})';
 
-            $pageRenderer = \TYPO3\CMS\Core\Utility\GeneralUtility::makeInstance(\TYPO3\CMS\Core\Page\PageRenderer::class);
+            $pageRenderer = GeneralUtility::makeInstance(PageRenderer::class);
             $pageRenderer->addJsFooterInlineCode('tx-dfgviewer-footer', $javascriptFooter);
         }
     }