diff --git a/components/ILIAS/DidacticTemplate/classes/Action/class.ilDidacticTemplateAction.php b/components/ILIAS/DidacticTemplate/classes/Action/class.ilDidacticTemplateAction.php
index f6c191356505..d4974fffea63 100755
--- a/components/ILIAS/DidacticTemplate/classes/Action/class.ilDidacticTemplateAction.php
+++ b/components/ILIAS/DidacticTemplate/classes/Action/class.ilDidacticTemplateAction.php
@@ -24,27 +24,25 @@
  */
 abstract class ilDidacticTemplateAction
 {
-    public const TYPE_LOCAL_POLICY = 1;
-    public const TYPE_LOCAL_ROLE = 2;
-    public const TYPE_BLOCK_ROLE = 3;
+    public const int TYPE_LOCAL_POLICY = 1;
+    public const int TYPE_LOCAL_ROLE = 2;
+    public const int TYPE_BLOCK_ROLE = 3;
 
-    public const FILTER_SOURCE_TITLE = 1;
-    public const FILTER_SOURCE_OBJ_ID = 2;
-    public const FILTER_PARENT_ROLES = 3;
-    public const FILTER_LOCAL_ROLES = 4;
-
-    public const PATTERN_PARENT_TYPE = 'action';
+    public const int FILTER_SOURCE_TITLE = 1;
+    public const int FILTER_SOURCE_OBJ_ID = 2;
+    public const int FILTER_PARENT_ROLES = 3;
+    public const int FILTER_LOCAL_ROLES = 4;
+    public const string PATTERN_PARENT_TYPE = 'action';
 
     protected ilLogger $logger;
     protected ilDBInterface $db;
     protected ilRbacReview $review;
     protected ilRbacAdmin $admin;
 
-    private int $action_id = 0;
-    private int $tpl_id = 0;
-    private int $type = 0;
-
-    private int $ref_id = 0;
+    protected int $action_id = 0;
+    protected int $tpl_id = 0;
+    protected int $type = 0;
+    protected int $ref_id = 0;
 
     public function __construct(int $action_id = 0)
     {
diff --git a/components/ILIAS/DidacticTemplate/classes/Action/class.ilDidacticTemplateLocalPolicyAction.php b/components/ILIAS/DidacticTemplate/classes/Action/class.ilDidacticTemplateLocalPolicyAction.php
index a1ace5cbac91..fd63fdd1589f 100755
--- a/components/ILIAS/DidacticTemplate/classes/Action/class.ilDidacticTemplateLocalPolicyAction.php
+++ b/components/ILIAS/DidacticTemplate/classes/Action/class.ilDidacticTemplateLocalPolicyAction.php
@@ -24,11 +24,11 @@
  */
 class ilDidacticTemplateLocalPolicyAction extends ilDidacticTemplateAction
 {
-    public const TPL_ACTION_OVERWRITE = 1;
-    public const TPL_ACTION_INTERSECT = 2;
-    public const TPL_ACTION_ADD = 3;
-    public const TPL_ACTION_SUBTRACT = 4;
-    public const TPL_ACTION_UNION = 5;
+    public const int TPL_ACTION_OVERWRITE = 1;
+    public const int TPL_ACTION_INTERSECT = 2;
+    public const int TPL_ACTION_ADD = 3;
+    public const int TPL_ACTION_SUBTRACT = 4;
+    public const int TPL_ACTION_UNION = 5;
 
     /** @var ilDidacticTemplateFilterPattern[] */
     private array $pattern = [];
diff --git a/components/ILIAS/DidacticTemplate/classes/Icon/class.ilDidacticTemplateIconHandler.php b/components/ILIAS/DidacticTemplate/classes/Icon/class.ilDidacticTemplateIconHandler.php
index e9ae50bdfc7b..d3f4e208025a 100755
--- a/components/ILIAS/DidacticTemplate/classes/Icon/class.ilDidacticTemplateIconHandler.php
+++ b/components/ILIAS/DidacticTemplate/classes/Icon/class.ilDidacticTemplateIconHandler.php
@@ -33,8 +33,7 @@
  */
 class ilDidacticTemplateIconHandler
 {
-    protected const WEBDIR_PREFIX = 'ilDidacticTemplateIcons';
-
+    protected const string WEBDIR_PREFIX = 'ilDidacticTemplateIcons';
     protected ilDidacticTemplateSetting $settings;
     protected ilLogger $logger;
     protected Filesystem $webDirectory;
diff --git a/components/ILIAS/DidacticTemplate/classes/Multilingualism/class.ilMultilingualism.php b/components/ILIAS/DidacticTemplate/classes/Multilingualism/class.ilMultilingualism.php
index 527d2043f285..56f2f8a3735a 100755
--- a/components/ILIAS/DidacticTemplate/classes/Multilingualism/class.ilMultilingualism.php
+++ b/components/ILIAS/DidacticTemplate/classes/Multilingualism/class.ilMultilingualism.php
@@ -16,6 +16,8 @@
  *
  *********************************************************************/
 
+declare(strict_types=1);
+
 /**
  * Class handles translation mode for an object.
  *
@@ -301,9 +303,9 @@ public function fromXML(SimpleXMLElement $root): void
 
         foreach ($root->translation as $trans) {
             $this->addLanguage(
-                trim($trans["language"]),
-                trim($trans->title),
-                trim($trans->description),
+                trim((string) $trans["language"]),
+                trim((string) $trans->title),
+                trim((string) $trans->description),
                 (int) $trans["default"] !== 0
             );
         }
diff --git a/components/ILIAS/DidacticTemplate/classes/Multilingualism/class.ilMultilingualismGUI.php b/components/ILIAS/DidacticTemplate/classes/Multilingualism/class.ilMultilingualismGUI.php
index 536d4cdfce32..8403bfd0da15 100755
--- a/components/ILIAS/DidacticTemplate/classes/Multilingualism/class.ilMultilingualismGUI.php
+++ b/components/ILIAS/DidacticTemplate/classes/Multilingualism/class.ilMultilingualismGUI.php
@@ -16,12 +16,14 @@
  *
  *********************************************************************/
 
+declare(strict_types=1);
+
 use ILIAS\MetaData\Services\ServicesInterface as LOMServices;
 
 /**
  * GUI class for object translation handling.
  * @author Alexander Killing <killing@leifos.de>
- * @ilCtrl_IsCalledBy ilMultilingualismeGUI: ilDidacticTemplateSettingsGUI
+ * @ilCtrl_IsCalledBy ilMultilingualismGUI: ilDidacticTemplateSettingsGUI
  */
 class ilMultilingualismGUI
 {
@@ -52,7 +54,7 @@ public function __construct(
         $this->lom_services = $DIC->learningObjectMetadata();
 
         $this->obj_trans = ilMultilingualism::getInstance($a_obj_id, $a_type);
-        $this->request = new \ILIAS\Multilingualism\StandardGUIRequest(
+        $this->request = new \ILIAS\DidacticTemplate\Multilingualism\StandardGUIRequest(
             $DIC->http(),
             $DIC->refinery()
         );
@@ -76,18 +78,12 @@ public function getTitleDescrOnlyMode(): bool
 
     public function executeCommand(): void
     {
-        $next_class = $this->ctrl->getNextClass($this);
-
-        switch ($next_class) {
-            default:
-                $cmd = $this->ctrl->getCmd("listTranslations");
-                if (in_array($cmd, array("listTranslations", "saveTranslations",
-                    "addTranslation", "deleteTranslations", "activateContentMultilinguality",
-                    "confirmRemoveLanguages", "removeLanguages", "confirmDeactivateContentMultiLang", "saveLanguages",
-                    "saveContentTranslationActivation", "deactivateContentMultiLang", "addLanguages"))) {
-                    $this->$cmd();
-                }
-                break;
+        $cmd = $this->ctrl->getCmd("listTranslations");
+        if (in_array($cmd, array("listTranslations", "saveTranslations",
+            "addTranslation", "deleteTranslations", "activateContentMultilinguality",
+            "confirmRemoveLanguages", "removeLanguages", "confirmDeactivateContentMultiLang", "saveLanguages",
+            "saveContentTranslationActivation", "deactivateContentMultiLang", "addLanguages"))) {
+            $this->$cmd();
         }
     }
 
@@ -391,8 +387,8 @@ public function removeLanguages(): void
         if (count($post_langs) > 0) {
             $langs = $this->obj_trans->getLanguages();
             foreach ($langs as $k => $l) {
-                if (in_array($l, $post_langs)) {
-                    $this->obj_trans->removeLanguage($l);
+                if (in_array($k, $post_langs)) {
+                    $this->obj_trans->removeLanguage($k);
                 }
             }
             $this->obj_trans->save();
diff --git a/components/ILIAS/DidacticTemplate/classes/Multilingualism/class.ilMultilingualismTableGUI.php b/components/ILIAS/DidacticTemplate/classes/Multilingualism/class.ilMultilingualismTableGUI.php
index 814fc1b1fef2..de06955825eb 100755
--- a/components/ILIAS/DidacticTemplate/classes/Multilingualism/class.ilMultilingualismTableGUI.php
+++ b/components/ILIAS/DidacticTemplate/classes/Multilingualism/class.ilMultilingualismTableGUI.php
@@ -16,6 +16,8 @@
  *
  *********************************************************************/
 
+declare(strict_types=1);
+
 use ILIAS\MetaData\Services\ServicesInterface as LOMServices;
 
 /**
diff --git a/components/ILIAS/DidacticTemplate/classes/Pattern/class.ilDidacticTemplateExcludeFilterPattern.php b/components/ILIAS/DidacticTemplate/classes/Pattern/class.ilDidacticTemplateExcludeFilterPattern.php
index 2c6283876be8..9852862c128c 100755
--- a/components/ILIAS/DidacticTemplate/classes/Pattern/class.ilDidacticTemplateExcludeFilterPattern.php
+++ b/components/ILIAS/DidacticTemplate/classes/Pattern/class.ilDidacticTemplateExcludeFilterPattern.php
@@ -35,11 +35,10 @@ public function __construct(int $a_pattern_id = 0)
      */
     public function valid(string $a_source): bool
     {
-        $a_source = trim($a_source);
-        switch ($this->getPatternSubType()) {
-            case self::PATTERN_SUBTYPE_REGEX:
-                $this->logger->debug('Checking exclude pattern with ' . $a_source . ' against ' . $this->getPattern());
-                return preg_match('/' . $this->getPattern() . '/', $a_source) !== 1;
+        if ($this->getPatternSubType() === self::PATTERN_SUBTYPE_REGEX) {
+            $a_source = trim($a_source);
+            $this->logger->debug('Checking exclude pattern with ' . $a_source . ' against ' . $this->getPattern());
+            return preg_match('/' . $this->getPattern() . '/', $a_source) !== 1;
         }
         return true;
     }
diff --git a/components/ILIAS/DidacticTemplate/classes/Pattern/class.ilDidacticTemplateFilterPattern.php b/components/ILIAS/DidacticTemplate/classes/Pattern/class.ilDidacticTemplateFilterPattern.php
index 984b3392d58d..68f01defa33a 100755
--- a/components/ILIAS/DidacticTemplate/classes/Pattern/class.ilDidacticTemplateFilterPattern.php
+++ b/components/ILIAS/DidacticTemplate/classes/Pattern/class.ilDidacticTemplateFilterPattern.php
@@ -24,20 +24,15 @@
  */
 abstract class ilDidacticTemplateFilterPattern
 {
-    public const PATTERN_INCLUDE = 1;
-    public const PATTERN_EXCLUDE = 2;
-
-    public const PATTERN_SUBTYPE_REGEX = 1;
-
-    private int $pattern_id = 0;
-
-    private int $parent_id = 0;
-    private string $parent_type = '';
-
-    private string $pattern = '';
-    private int $pattern_type = 0;
-    private int $pattern_sub_type = 0;
-
+    public const int PATTERN_INCLUDE = 1;
+    public const int PATTERN_EXCLUDE = 2;
+    public const int PATTERN_SUBTYPE_REGEX = 1;
+    protected string $parent_type = '';
+    protected string $pattern = '';
+    protected int $pattern_id = 0;
+    protected int $parent_id = 0;
+    protected int $pattern_type = 0;
+    protected int $pattern_sub_type = 0;
     protected ilDBInterface $db;
     protected ilLogger $logger;
 
@@ -116,15 +111,11 @@ public function getPattern(): string
 
     /**
      * Check if pattern matches
-     * @param mixed
-     * @return bool
      */
     abstract public function valid(string $a_source): bool;
 
     /**
      * Get xml representation of pattern
-     * @param ilXmlWriter $writer
-     * @return string
      */
     abstract public function toXml(ilXmlWriter $writer): void;
 
diff --git a/components/ILIAS/DidacticTemplate/classes/Pattern/class.ilDidacticTemplateIncludeFilterPattern.php b/components/ILIAS/DidacticTemplate/classes/Pattern/class.ilDidacticTemplateIncludeFilterPattern.php
index 362a204be0ea..fabbdbd7eb58 100755
--- a/components/ILIAS/DidacticTemplate/classes/Pattern/class.ilDidacticTemplateIncludeFilterPattern.php
+++ b/components/ILIAS/DidacticTemplate/classes/Pattern/class.ilDidacticTemplateIncludeFilterPattern.php
@@ -32,11 +32,10 @@ public function __construct(int $a_pattern_id = 0)
 
     public function valid(string $a_source): bool
     {
-        $a_source = trim($a_source);
-        switch ($this->getPatternSubType()) {
-            case self::PATTERN_SUBTYPE_REGEX:
-                $this->logger->debug('Checking include pattern with ' . $a_source . ' against ' . $this->getPattern());
-                return preg_match('/' . $this->getPattern() . '/', $a_source) === 1;
+        if ($this->getPatternSubType() === self::PATTERN_SUBTYPE_REGEX) {
+            $a_source = trim($a_source);
+            $this->logger->debug('Checking include pattern with ' . $a_source . ' against ' . $this->getPattern());
+            return preg_match('/' . $this->getPattern() . '/', $a_source) === 1;
         }
         return false;
     }
diff --git a/components/ILIAS/DidacticTemplate/classes/Setting/class.ilDidacticTemplateSetting.php b/components/ILIAS/DidacticTemplate/classes/Setting/class.ilDidacticTemplateSetting.php
index 9d642894d1a9..18710606222a 100755
--- a/components/ILIAS/DidacticTemplate/classes/Setting/class.ilDidacticTemplateSetting.php
+++ b/components/ILIAS/DidacticTemplate/classes/Setting/class.ilDidacticTemplateSetting.php
@@ -25,8 +25,7 @@
  */
 class ilDidacticTemplateSetting
 {
-    public const TYPE_CREATION = 1;
-
+    public const int TYPE_CREATION = 1;
     private int $id = 0;
     private bool $enabled = false;
     private string $title = '';
@@ -474,12 +473,8 @@ protected function read(): bool
 
     public function toXml(ilXmlWriter $writer): ilXmlWriter
     {
-        $type = '';
-        switch ($this->getType()) {
-            case self::TYPE_CREATION:
-                $type = 'creation';
-                break;
-        }
+        $type = ($this->getType() === self::TYPE_CREATION) ? 'creation' : '';
+
         $writer->xmlStartTag('didacticTemplate', ['type' => $type]);
         $writer->xmlElement('title', [], $this->getTitle());
         $writer->xmlElement('description', [], $this->getDescription());
@@ -489,8 +484,7 @@ public function toXml(ilXmlWriter $writer): ilXmlWriter
         // info text with p-tags
         if ($this->getInfo() !== '') {
             $writer->xmlStartTag('info');
-
-            $info_lines = (array) explode("\n", $this->getInfo());
+            $info_lines = explode("\n", $this->getInfo());
             foreach ($info_lines as $info) {
                 $trimmed_info = trim($info);
                 if ($trimmed_info !== '') {
diff --git a/components/ILIAS/DidacticTemplate/classes/Setting/class.ilDidacticTemplateSettingsGUI.php b/components/ILIAS/DidacticTemplate/classes/Setting/class.ilDidacticTemplateSettingsGUI.php
index c02dc74d5109..8a2c6179f9a2 100755
--- a/components/ILIAS/DidacticTemplate/classes/Setting/class.ilDidacticTemplateSettingsGUI.php
+++ b/components/ILIAS/DidacticTemplate/classes/Setting/class.ilDidacticTemplateSettingsGUI.php
@@ -503,7 +503,7 @@ protected function initEditTemplate(ilDidacticTemplateSetting $set): ilPropertyF
                     }
                 }
                 $title->setInfo($this->lng->txt("language") . ": " . $language .
-                    ' <a href="' . $this->ctrl->getLinkTargetByClass("ilmultilingualismgui", "listTranslations") .
+                    ' <a href="' . $this->ctrl->getLinkTargetByClass(ilMultilingualismGUI::class, "listTranslations") .
                     '">&raquo; ' . $this->lng->txt("more_translations") . '</a>');
             }
         }
@@ -752,7 +752,7 @@ protected function setEditTabs(string $a_tab_active = "edit"): void
                 $this->tabs->addSubTab(
                     'settings_trans',
                     $this->lng->txt("obj_multilinguality"),
-                    $this->ctrl->getLinkTargetByClass(["ilmultilingualismgui"], 'listTranslations')
+                    $this->ctrl->getLinkTargetByClass(ilMultilingualismGUI::class, 'listTranslations')
                 );
                 $this->tabs->setTabActive('edit');
                 $this->tabs->setSubTabActive($a_tab_active);
diff --git a/components/ILIAS/DidacticTemplate/classes/Setting/class.ilDidacticTemplateSettingsTableFilter.php b/components/ILIAS/DidacticTemplate/classes/Setting/class.ilDidacticTemplateSettingsTableFilter.php
index 6919fa608159..71b7d05a0e0b 100755
--- a/components/ILIAS/DidacticTemplate/classes/Setting/class.ilDidacticTemplateSettingsTableFilter.php
+++ b/components/ILIAS/DidacticTemplate/classes/Setting/class.ilDidacticTemplateSettingsTableFilter.php
@@ -23,18 +23,16 @@
 
 class ilDidacticTemplateSettingsTableFilter
 {
-    protected const FILTER_ID = 'otpl_templates_table';
-
-    protected const FILTER_NAME_ICON = 'icon';
-    protected const FILTER_NAME_TITLE = 'title';
-    protected const FILTER_NAME_TYPE = 'type';
-    protected const FILTER_NAME_SCOPE = 'scope';
-    protected const FILTER_NAME_ACTIVE = 'active';
-
-    protected const FILTER_ON = 1;
-    protected const FILTER_OFF = 2;
-    protected const FILTER_GLOBAL = 1;
-    protected const FILTER_LOCAL = 2;
+    protected const string FILTER_ID = 'otpl_templates_table';
+    protected const string FILTER_NAME_ICON = 'icon';
+    protected const string FILTER_NAME_TITLE = 'title';
+    protected const string FILTER_NAME_TYPE = 'type';
+    protected const string FILTER_NAME_SCOPE = 'scope';
+    protected const string FILTER_NAME_ACTIVE = 'active';
+    protected const int FILTER_ON = 1;
+    protected const int FILTER_OFF = 2;
+    protected const int FILTER_GLOBAL = 1;
+    protected const int FILTER_LOCAL = 2;
 
     private array $input_activation_config = [
         self::FILTER_NAME_ICON => false,
diff --git a/components/ILIAS/DidacticTemplate/classes/class.ilDidacticTemplateGUI.php b/components/ILIAS/DidacticTemplate/classes/class.ilDidacticTemplateGUI.php
index f030489b457a..343ebf00903f 100755
--- a/components/ILIAS/DidacticTemplate/classes/class.ilDidacticTemplateGUI.php
+++ b/components/ILIAS/DidacticTemplate/classes/class.ilDidacticTemplateGUI.php
@@ -77,16 +77,8 @@ public function executeCommand(): void
     {
         $next_class = $this->ctrl->getNextClass($this);
         $cmd = $this->ctrl->getCmd();
-
-        switch ($next_class) {
-            default:
-                if (!$cmd) {
-                    $cmd = 'overview';
-                }
-                $this->$cmd();
-
-                break;
-        }
+        $cmd = !$cmd ? 'overview' : $cmd;
+        $this->$cmd();
     }
 
     public function appendToolbarSwitch(ilToolbarGUI $toolbar, string $a_obj_type, int $a_ref_id): bool
diff --git a/components/ILIAS/DidacticTemplate/classes/class.ilDidacticTemplateImport.php b/components/ILIAS/DidacticTemplate/classes/class.ilDidacticTemplateImport.php
index 5bcee0c19067..fdee5e9c2850 100755
--- a/components/ILIAS/DidacticTemplate/classes/class.ilDidacticTemplateImport.php
+++ b/components/ILIAS/DidacticTemplate/classes/class.ilDidacticTemplateImport.php
@@ -30,12 +30,11 @@
  */
 class ilDidacticTemplateImport
 {
-    protected const XML_ELEMENT_NAME_LOCAL_ROLE_ACTION = 'localRoleAction';
-    protected const XML_ELEMENT_NAME_BLOCK_ROLE_ACIONE = 'blockRoleAction';
-    protected const XML_ELEMENT_NAME_LOCAL_POLICY_ACTION = 'localPolicyAction';
-    public const IMPORT_FILE = 1;
-    protected const SCHEMA_TYPE = 'otpl';
-
+    protected const string XML_ELEMENT_NAME_LOCAL_ROLE_ACTION = 'localRoleAction';
+    protected const string XML_ELEMENT_NAME_BLOCK_ROLE_ACIONE = 'blockRoleAction';
+    protected const string XML_ELEMENT_NAME_LOCAL_POLICY_ACTION = 'localPolicyAction';
+    protected const string SCHEMA_TYPE = 'otpl';
+    public const int IMPORT_FILE = 1;
     protected int $type = 0;
     protected string $xmlfile = '';
     protected ilLogger $logger;
@@ -71,13 +70,8 @@ public function getInputType(): int
      */
     public function import(int $a_dtpl_id = 0): ilDidacticTemplateSetting
     {
-        $root = null;
         $use_internal_errors = libxml_use_internal_errors(true);
-        switch ($this->getInputType()) {
-            case self::IMPORT_FILE:
-                $root = simplexml_load_string(file_get_contents($this->getInputFile()));
-                break;
-        }
+        $root = ($this->getInputType() === self::IMPORT_FILE) ? simplexml_load_string(file_get_contents($this->getInputFile())) : null;
         libxml_use_internal_errors($use_internal_errors);
         if (!$root instanceof SimpleXMLElement) {
             throw new ilDidacticTemplateImportException(
@@ -322,7 +316,6 @@ protected function parseActions(ilDidacticTemplateSetting $set, ?SimpleXMLElemen
             }
             if ($action->getName() === self::XML_ELEMENT_NAME_LOCAL_POLICY_ACTION) {
                 $this->parseLocalPolicyAction($set, $action);
-                continue;
             }
         }
     }