diff --git a/Account/Account.php b/Account/Account.php
index a6fc54888..33f9ae6ec 100644
--- a/Account/Account.php
+++ b/Account/Account.php
@@ -169,7 +169,7 @@ class Account implements ArrayableInterface, \JsonSerializable
         $this->createdAt  = new \DateTime('now');
         $this->lastActive = new \DateTime('now');
         $this->id         = $id;
-        $this->l11n       = new NullLocalization();
+        $this->l11n       = new Localization();
     }
 
     /**
diff --git a/Account/AccountManager.php b/Account/AccountManager.php
index 9867f6adb..dfdbb99be 100644
--- a/Account/AccountManager.php
+++ b/Account/AccountManager.php
@@ -27,7 +27,7 @@ use phpOMS\DataStorage\Session\SessionInterface;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class AccountManager implements \Countable
+final class AccountManager implements \Countable
 {
 
     /**
diff --git a/Account/NullAccount.php b/Account/NullAccount.php
index 50a55ee41..4d14d18c0 100644
--- a/Account/NullAccount.php
+++ b/Account/NullAccount.php
@@ -22,6 +22,6 @@ namespace phpOMS\Account;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class NullAccount extends Account
+final class NullAccount extends Account
 {
 }
diff --git a/Asset/AssetManager.php b/Asset/AssetManager.php
index 4c022a834..5743d1cb6 100644
--- a/Asset/AssetManager.php
+++ b/Asset/AssetManager.php
@@ -22,7 +22,7 @@ namespace phpOMS\Asset;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class AssetManager implements \Countable
+final class AssetManager implements \Countable
 {
 
     /**
diff --git a/Auth/Auth.php b/Auth/Auth.php
index ccd46ccb0..b77d8b5cf 100644
--- a/Auth/Auth.php
+++ b/Auth/Auth.php
@@ -26,7 +26,7 @@ use phpOMS\DataStorage\Session\SessionInterface;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class Auth
+final class Auth
 {
     /**
      * Constructor.
diff --git a/AutoloadException.php b/AutoloadException.php
index e4fd2a32f..3a6b63d48 100644
--- a/AutoloadException.php
+++ b/AutoloadException.php
@@ -24,7 +24,7 @@ namespace phpOMS;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class AutoloadException extends \RuntimeException
+final class AutoloadException extends \RuntimeException
 {
     /**
      * Constructor.
diff --git a/Autoloader.php b/Autoloader.php
index 523385d9f..762ade0b2 100644
--- a/Autoloader.php
+++ b/Autoloader.php
@@ -24,7 +24,7 @@ spl_autoload_register('\phpOMS\Autoloader::defaultAutoloader');
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class Autoloader
+final class Autoloader
 {
     /**
      * Base paths for autoloading
@@ -36,6 +36,17 @@ class Autoloader
         __DIR__ . '/../',
         __DIR__ . '/../../',
     ];
+
+    /**
+     * Constructor.
+     *
+     * @since  1.0.0
+     * @codeCoverageIgnore
+     */
+    private function __construct()
+    {
+
+    }
     
     /**
      * Add base path for autoloading
diff --git a/Business/Finance/Depreciation.php b/Business/Finance/Depreciation.php
index 2fbf05de3..6a7c3ecbf 100644
--- a/Business/Finance/Depreciation.php
+++ b/Business/Finance/Depreciation.php
@@ -22,7 +22,7 @@ namespace phpOMS\Business\Finance;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class Depreciation
+final class Depreciation
 {
     /**
      * Calculate linear depretiation rate
diff --git a/Business/Finance/FinanceFormulas.php b/Business/Finance/FinanceFormulas.php
index 32c16bf62..6630eda16 100644
--- a/Business/Finance/FinanceFormulas.php
+++ b/Business/Finance/FinanceFormulas.php
@@ -28,7 +28,7 @@ use phpOMS\Math\Matrix\Exception\InvalidDimensionException;
  * @SuppressWarnings(PHPMD.CamelCaseParameterName)
  * @SuppressWarnings(PHPMD.CamelCaseVariableName)
  */
-class FinanceFormulas
+final class FinanceFormulas
 {
 
     /**
diff --git a/Business/Finance/Loan.php b/Business/Finance/Loan.php
index ac7c60303..c76f3cc5b 100644
--- a/Business/Finance/Loan.php
+++ b/Business/Finance/Loan.php
@@ -25,7 +25,7 @@ namespace phpOMS\Business\Finance;
  * @SuppressWarnings(PHPMD.CamelCaseParameterName)
  * @SuppressWarnings(PHPMD.CamelCaseVariableName)
  */
-class Loan
+final class Loan
 {
     /**
      * Balloon Loan - Payments
diff --git a/Business/Finance/Lorenzkurve.php b/Business/Finance/Lorenzkurve.php
index ff224ed97..3d64eae7a 100644
--- a/Business/Finance/Lorenzkurve.php
+++ b/Business/Finance/Lorenzkurve.php
@@ -22,7 +22,7 @@ namespace phpOMS\Business\Finance;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class Lorenzkurve
+final class Lorenzkurve
 {
     /**
      * Calculate Gini coefficient
diff --git a/Business/Finance/StockBonds.php b/Business/Finance/StockBonds.php
index 3ba8fba66..9ee58eb7c 100644
--- a/Business/Finance/StockBonds.php
+++ b/Business/Finance/StockBonds.php
@@ -25,7 +25,7 @@ namespace phpOMS\Business\Finance;
  * @SuppressWarnings(PHPMD.CamelCaseParameterName)
  * @SuppressWarnings(PHPMD.CamelCaseVariableName)
  */
-class StockBonds
+final class StockBonds
 {
     /**
      * Bond Equivalent Yield
diff --git a/Business/Marketing/Metrics.php b/Business/Marketing/Metrics.php
index 620354de1..2480bffbc 100644
--- a/Business/Marketing/Metrics.php
+++ b/Business/Marketing/Metrics.php
@@ -24,7 +24,7 @@ namespace phpOMS\Business\Marketing;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class Metrics
+final class Metrics
 {
     /**
      * Calculate customer retention
diff --git a/Business/Marketing/NetPromoterScore.php b/Business/Marketing/NetPromoterScore.php
index 4de8e2bbb..a18e292ca 100644
--- a/Business/Marketing/NetPromoterScore.php
+++ b/Business/Marketing/NetPromoterScore.php
@@ -25,7 +25,7 @@ namespace phpOMS\Business\Marketing;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class NetPromoterScore
+final class NetPromoterScore
 {
     /**
      * Score values
diff --git a/Business/Programming/Metrics.php b/Business/Programming/Metrics.php
index bcd2de5bd..855b88f12 100644
--- a/Business/Programming/Metrics.php
+++ b/Business/Programming/Metrics.php
@@ -24,7 +24,7 @@ namespace phpOMS\Business\Programming;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class Metrics
+final class Metrics
 {
     /**
      * Calculate ABC metric score
diff --git a/Business/Sales/MarketShareEstimation.php b/Business/Sales/MarketShareEstimation.php
index 232af05bd..6d60784c2 100644
--- a/Business/Sales/MarketShareEstimation.php
+++ b/Business/Sales/MarketShareEstimation.php
@@ -25,7 +25,7 @@ namespace phpOMS\Business\Sales;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class MarketShareEstimation
+final class MarketShareEstimation
 {
     /**
      * Calculate rank (r) based on market share (m)
diff --git a/DataStorage/Cache/CachePool.php b/DataStorage/Cache/CachePool.php
index 4b2047e13..3daf22cfc 100644
--- a/DataStorage/Cache/CachePool.php
+++ b/DataStorage/Cache/CachePool.php
@@ -30,7 +30,7 @@ use phpOMS\DataStorage\Cache\Connection\NullCache;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class CachePool implements DataStoragePoolInterface
+final class CachePool implements DataStoragePoolInterface
 {
     /**
      * MemCache instance.
diff --git a/DataStorage/Cookie/CookieJar.php b/DataStorage/Cookie/CookieJar.php
index 78ef8df4d..fd207f9e9 100644
--- a/DataStorage/Cookie/CookieJar.php
+++ b/DataStorage/Cookie/CookieJar.php
@@ -24,7 +24,7 @@ use phpOMS\DataStorage\LockException;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class CookieJar
+final class CookieJar
 {
     /**
      * Locked.
diff --git a/DataStorage/Database/Connection/ConnectionFactory.php b/DataStorage/Database/Connection/ConnectionFactory.php
index 4950d55b3..06016d28d 100644
--- a/DataStorage/Database/Connection/ConnectionFactory.php
+++ b/DataStorage/Database/Connection/ConnectionFactory.php
@@ -24,7 +24,7 @@ use phpOMS\DataStorage\Database\DatabaseType;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class ConnectionFactory
+final class ConnectionFactory
 {
 
     /**
diff --git a/DataStorage/Database/Connection/MysqlConnection.php b/DataStorage/Database/Connection/MysqlConnection.php
index 4aefd867e..3e41ba8ab 100644
--- a/DataStorage/Database/Connection/MysqlConnection.php
+++ b/DataStorage/Database/Connection/MysqlConnection.php
@@ -31,7 +31,7 @@ use phpOMS\DataStorage\Database\Exception\InvalidConnectionConfigException;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class MysqlConnection extends ConnectionAbstract
+final class MysqlConnection extends ConnectionAbstract
 {
 
     /**
diff --git a/DataStorage/Database/Connection/NullConnection.php b/DataStorage/Database/Connection/NullConnection.php
index ff837bba2..dfeadf605 100644
--- a/DataStorage/Database/Connection/NullConnection.php
+++ b/DataStorage/Database/Connection/NullConnection.php
@@ -24,7 +24,7 @@ use phpOMS\DataStorage\Database\Exception\InvalidConnectionConfigException;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class NullConnection extends ConnectionAbstract
+final class NullConnection extends ConnectionAbstract
 {
 
     /**
diff --git a/DataStorage/Database/Connection/PostgresConnection.php b/DataStorage/Database/Connection/PostgresConnection.php
index ea26caf5c..2f65da577 100644
--- a/DataStorage/Database/Connection/PostgresConnection.php
+++ b/DataStorage/Database/Connection/PostgresConnection.php
@@ -25,7 +25,7 @@ namespace phpOMS\DataStorage\Database\Connection;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-abstract class PostgresConnection extends \Exception
+final  class PostgresConnection extends \Exception
 {
 
 }
diff --git a/DataStorage/Database/Connection/SQLiteConnection.php b/DataStorage/Database/Connection/SQLiteConnection.php
index 2404b1d0e..02f1db516 100644
--- a/DataStorage/Database/Connection/SQLiteConnection.php
+++ b/DataStorage/Database/Connection/SQLiteConnection.php
@@ -29,7 +29,7 @@ use phpOMS\DataStorage\Database\Query\Grammar\SqliteGrammar;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class SqliteConnection extends ConnectionAbstract
+final class SqliteConnection extends ConnectionAbstract
 {
 
     /**
diff --git a/DataStorage/Database/Connection/SqlServerConnection.php b/DataStorage/Database/Connection/SqlServerConnection.php
index 5acda01ac..99d085825 100644
--- a/DataStorage/Database/Connection/SqlServerConnection.php
+++ b/DataStorage/Database/Connection/SqlServerConnection.php
@@ -30,7 +30,7 @@ use phpOMS\DataStorage\Database\Schema\Grammar\MysqlGrammar as MysqlSchemaGramma
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class SqlServerConnection extends ConnectionAbstract
+final class SqlServerConnection extends ConnectionAbstract
 {
     /**
      * Object constructor.
diff --git a/DataStorage/Database/DatabasePool.php b/DataStorage/Database/DatabasePool.php
index df1fadf2a..5668f8222 100644
--- a/DataStorage/Database/DatabasePool.php
+++ b/DataStorage/Database/DatabasePool.php
@@ -29,7 +29,7 @@ use phpOMS\DataStorage\Database\Connection\NullConnection;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class DatabasePool implements DataStoragePoolInterface
+final class DatabasePool implements DataStoragePoolInterface
 {
 
     /**
diff --git a/DataStorage/Database/Exception/InvalidConnectionConfigException.php b/DataStorage/Database/Exception/InvalidConnectionConfigException.php
index 77ec24a0b..65f66ae63 100644
--- a/DataStorage/Database/Exception/InvalidConnectionConfigException.php
+++ b/DataStorage/Database/Exception/InvalidConnectionConfigException.php
@@ -22,7 +22,7 @@ namespace phpOMS\DataStorage\Database\Exception;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class InvalidConnectionConfigException extends \InvalidArgumentException
+final class InvalidConnectionConfigException extends \InvalidArgumentException
 {
     /**
      * Constructor.
diff --git a/DataStorage/Database/Exception/InvalidDatabaseTypeException.php b/DataStorage/Database/Exception/InvalidDatabaseTypeException.php
index 010a4c7ba..e2500d4ee 100644
--- a/DataStorage/Database/Exception/InvalidDatabaseTypeException.php
+++ b/DataStorage/Database/Exception/InvalidDatabaseTypeException.php
@@ -22,7 +22,7 @@ namespace phpOMS\DataStorage\Database\Exception;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class InvalidDatabaseTypeException extends \InvalidArgumentException
+final class InvalidDatabaseTypeException extends \InvalidArgumentException
 {
     /**
      * Constructor.
diff --git a/DataStorage/Database/Exception/InvalidMapperException.php b/DataStorage/Database/Exception/InvalidMapperException.php
index 4885c55ea..110bcd6a4 100644
--- a/DataStorage/Database/Exception/InvalidMapperException.php
+++ b/DataStorage/Database/Exception/InvalidMapperException.php
@@ -22,7 +22,7 @@ namespace phpOMS\DataStorage\Database\Exception;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class InvalidMapperException extends \RuntimeException
+final class InvalidMapperException extends \RuntimeException
 {
     /**
      * Constructor.
diff --git a/DataStorage/Database/Query/Builder.php b/DataStorage/Database/Query/Builder.php
index 727f18bf2..4fb668335 100644
--- a/DataStorage/Database/Query/Builder.php
+++ b/DataStorage/Database/Query/Builder.php
@@ -25,7 +25,7 @@ use phpOMS\DataStorage\Database\Connection\ConnectionAbstract;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class Builder extends BuilderAbstract
+final class Builder extends BuilderAbstract
 {
     /**
      * Is read only.
diff --git a/DataStorage/LockException.php b/DataStorage/LockException.php
index 0443463d3..61a0922b0 100644
--- a/DataStorage/LockException.php
+++ b/DataStorage/LockException.php
@@ -22,7 +22,7 @@ namespace phpOMS\DataStorage;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class LockException extends \RuntimeException
+final class LockException extends \RuntimeException
 {
     /**
      * Constructor.
diff --git a/Dispatcher/Dispatcher.php b/Dispatcher/Dispatcher.php
index 7b883a1a0..5113b66fa 100644
--- a/Dispatcher/Dispatcher.php
+++ b/Dispatcher/Dispatcher.php
@@ -26,7 +26,7 @@ use phpOMS\System\File\PathException;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class Dispatcher
+final class Dispatcher
 {
 
     /**
diff --git a/Event/EventManager.php b/Event/EventManager.php
index c48d365ff..a3a75b201 100644
--- a/Event/EventManager.php
+++ b/Event/EventManager.php
@@ -24,7 +24,7 @@ namespace phpOMS\Event;
  *
  * @todo       : make cachable + database storable -> can reload user defined listeners (persistent events)
  */
-class EventManager
+final class EventManager
 {
     /**
      * Events.
diff --git a/Localization/L11nManager.php b/Localization/L11nManager.php
index b7de5cac4..4c3f7e94e 100644
--- a/Localization/L11nManager.php
+++ b/Localization/L11nManager.php
@@ -25,7 +25,7 @@ use phpOMS\Module\ModuleAbstract;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class L11nManager
+final class L11nManager
 {
 
     /**
diff --git a/Localization/Localization.php b/Localization/Localization.php
index 1fa9fc8f8..f0ad0e8fb 100644
--- a/Localization/Localization.php
+++ b/Localization/Localization.php
@@ -26,7 +26,7 @@ use phpOMS\Utils\Converter\TemperatureType;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class Localization
+final class Localization
 {
 
     /**
diff --git a/Localization/Money.php b/Localization/Money.php
index 59bddc09c..f09878f33 100644
--- a/Localization/Money.php
+++ b/Localization/Money.php
@@ -22,7 +22,7 @@ namespace phpOMS\Localization;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class Money implements \Serializable
+final class Money implements \Serializable
 {
 
     /**
diff --git a/Localization/NullLocalization.php b/Localization/NullLocalization.php
index 9868d53da..f00ac1f3d 100644
--- a/Localization/NullLocalization.php
+++ b/Localization/NullLocalization.php
@@ -22,7 +22,7 @@ namespace phpOMS\Localization;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class NullLocalization extends Localization
+final class NullLocalizations
 {
 
 }
diff --git a/Log/FileLogger.php b/Log/FileLogger.php
index ba2d3a409..10828c6da 100644
--- a/Log/FileLogger.php
+++ b/Log/FileLogger.php
@@ -27,7 +27,7 @@ use phpOMS\System\File\Local\File;
  * 
  * @SuppressWarnings(PHPMD.Superglobals)
  */
-class FileLogger implements LoggerInterface
+final class FileLogger implements LoggerInterface
 {
     public const MSG_BACKTRACE = '{datetime}; {level}; {ip}; {message}; {backtrace}';
     public const MSG_FULL      = '{datetime}; {level}; {ip}; {line}; {version}; {os}; {path}; {message}; {file}; {backtrace}';
diff --git a/Math/Exception/ZeroDevisionException.php b/Math/Exception/ZeroDevisionException.php
index 94292f509..ed3ba5417 100644
--- a/Math/Exception/ZeroDevisionException.php
+++ b/Math/Exception/ZeroDevisionException.php
@@ -22,7 +22,7 @@ namespace phpOMS\Math\Exception;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class ZeroDevisionException extends \UnexpectedValueException
+final class ZeroDevisionException extends \UnexpectedValueException
 {
     /**
      * Constructor.
diff --git a/Math/Functions/Fibunacci.php b/Math/Functions/Fibunacci.php
index 7990fc8c2..f40c0aff9 100644
--- a/Math/Functions/Fibunacci.php
+++ b/Math/Functions/Fibunacci.php
@@ -24,8 +24,18 @@ use phpOMS\Math\Number\Numbers;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class Fibunacci
+final class Fibunacci
 {
+    /**
+     * Constructor.
+     *
+     * @since  1.0.0
+     * @codeCoverageIgnore
+     */
+    private function __construct()
+    {
+
+    }
 
     /**
      * Is fibunacci number.
diff --git a/Math/Functions/Functions.php b/Math/Functions/Functions.php
index 29d3fdb63..77f4004d0 100644
--- a/Math/Functions/Functions.php
+++ b/Math/Functions/Functions.php
@@ -22,8 +22,18 @@ namespace phpOMS\Math\Functions;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class Functions
+final class Functions
 {
+    /**
+     * Constructor.
+     *
+     * @since  1.0.0
+     * @codeCoverageIgnore
+     */
+    private function __construct()
+    {
+
+    }
     
     /**
      * Calculate gammar function value.
diff --git a/Math/Functions/Gamma.php b/Math/Functions/Gamma.php
index 5e2fbc71f..f6c4d5cd7 100644
--- a/Math/Functions/Gamma.php
+++ b/Math/Functions/Gamma.php
@@ -22,8 +22,19 @@ namespace phpOMS\Math\Functions;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class Gamma
+final class Gamma
 {
+    /**
+     * Constructor.
+     *
+     * @since  1.0.0
+     * @codeCoverageIgnore
+     */
+    private function __construct()
+    {
+
+    }
+    
     /**
      * approximation values.
      *
diff --git a/Math/Geometry/ConvexHull/MonotoneChain.php b/Math/Geometry/ConvexHull/MonotoneChain.php
index 0a07d6d16..7951d6368 100644
--- a/Math/Geometry/ConvexHull/MonotoneChain.php
+++ b/Math/Geometry/ConvexHull/MonotoneChain.php
@@ -26,6 +26,17 @@ namespace phpOMS\Math\Geometry\ConvexHull;
  */
 final class MonotoneChain
 {
+    /**
+     * Constructor.
+     *
+     * @since  1.0.0
+     * @codeCoverageIgnore
+     */
+    private function __construct()
+    {
+
+    }
+    
     /**
      * Create convex hull
      *
diff --git a/Math/Geometry/Shape/D2/Circle.php b/Math/Geometry/Shape/D2/Circle.php
index 572b18d07..535b37c34 100644
--- a/Math/Geometry/Shape/D2/Circle.php
+++ b/Math/Geometry/Shape/D2/Circle.php
@@ -22,7 +22,7 @@ namespace phpOMS\Math\Geometry\Shape\D2;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class Circle implements D2ShapeInterface
+final class Circle implements D2ShapeInterface
 {
 
     /**
diff --git a/Math/Geometry/Shape/D2/Ellipse.php b/Math/Geometry/Shape/D2/Ellipse.php
index 17d940c04..f1d417ba9 100644
--- a/Math/Geometry/Shape/D2/Ellipse.php
+++ b/Math/Geometry/Shape/D2/Ellipse.php
@@ -22,7 +22,7 @@ namespace phpOMS\Math\Geometry\Shape\D2;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class Ellipse implements D2ShapeInterface
+final class Ellipse implements D2ShapeInterface
 {
 
     /**
diff --git a/Math/Geometry/Shape/D2/Polygon.php b/Math/Geometry/Shape/D2/Polygon.php
index dd8bd5956..9e3168ae0 100644
--- a/Math/Geometry/Shape/D2/Polygon.php
+++ b/Math/Geometry/Shape/D2/Polygon.php
@@ -22,7 +22,7 @@ namespace phpOMS\Math\Geometry\Shape\D2;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class Polygon implements D2ShapeInterface
+final class Polygon implements D2ShapeInterface
 {
     /**
      * Epsilon for float comparison.
diff --git a/Math/Geometry/Shape/D2/Quadrilateral.php b/Math/Geometry/Shape/D2/Quadrilateral.php
index ab71a4b17..280d284c7 100644
--- a/Math/Geometry/Shape/D2/Quadrilateral.php
+++ b/Math/Geometry/Shape/D2/Quadrilateral.php
@@ -13,7 +13,7 @@
 declare(strict_types=1);
 namespace phpOMS\Math\Geometry\Shape\D2;
 
-class Quadrilateral implements D2ShapeInterface
+final class Quadrilateral implements D2ShapeInterface
 {
 
 }
diff --git a/Math/Geometry/Shape/D2/Rectangle.php b/Math/Geometry/Shape/D2/Rectangle.php
index 47c3efa61..8501309d4 100644
--- a/Math/Geometry/Shape/D2/Rectangle.php
+++ b/Math/Geometry/Shape/D2/Rectangle.php
@@ -22,7 +22,7 @@ namespace phpOMS\Math\Geometry\Shape\D2;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class Rectangle implements D2ShapeInterface
+final class Rectangle implements D2ShapeInterface
 {
 
     /**
diff --git a/Math/Geometry/Shape/D2/Trapezoid.php b/Math/Geometry/Shape/D2/Trapezoid.php
index ed3f671cf..d2c91b671 100644
--- a/Math/Geometry/Shape/D2/Trapezoid.php
+++ b/Math/Geometry/Shape/D2/Trapezoid.php
@@ -22,7 +22,7 @@ namespace phpOMS\Math\Geometry\Shape\D2;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class Trapezoid implements D2ShapeInterface
+final class Trapezoid implements D2ShapeInterface
 {
 
     /**
diff --git a/Math/Geometry/Shape/D2/Triangle.php b/Math/Geometry/Shape/D2/Triangle.php
index d6fec1613..003683718 100644
--- a/Math/Geometry/Shape/D2/Triangle.php
+++ b/Math/Geometry/Shape/D2/Triangle.php
@@ -22,7 +22,7 @@ namespace phpOMS\Math\Geometry\Shape\D2;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class Triangle implements D2ShapeInterface
+final class Triangle implements D2ShapeInterface
 {
 
     /**
diff --git a/Math/Geometry/Shape/D3/Cone.php b/Math/Geometry/Shape/D3/Cone.php
index d1522a7d5..c907ec70d 100644
--- a/Math/Geometry/Shape/D3/Cone.php
+++ b/Math/Geometry/Shape/D3/Cone.php
@@ -22,7 +22,7 @@ namespace phpOMS\Math\Geometry\Shape\D3;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class Cone implements D3ShapeInterface
+final class Cone implements D3ShapeInterface
 {
 
     /**
diff --git a/Math/Geometry/Shape/D3/Cuboid.php b/Math/Geometry/Shape/D3/Cuboid.php
index 637905613..3e09eb5d4 100644
--- a/Math/Geometry/Shape/D3/Cuboid.php
+++ b/Math/Geometry/Shape/D3/Cuboid.php
@@ -22,7 +22,7 @@ namespace phpOMS\Math\Geometry\Shape\D3;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class Cuboid implements D3ShapeInterface
+final class Cuboid implements D3ShapeInterface
 {
 
     /**
diff --git a/Math/Geometry/Shape/D3/Cylinder.php b/Math/Geometry/Shape/D3/Cylinder.php
index b4f0db363..a4a9c3962 100644
--- a/Math/Geometry/Shape/D3/Cylinder.php
+++ b/Math/Geometry/Shape/D3/Cylinder.php
@@ -22,7 +22,7 @@ namespace phpOMS\Math\Geometry\Shape\D3;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class Cylinder implements D3ShapeInterface
+final class Cylinder implements D3ShapeInterface
 {
 
     /**
diff --git a/Math/Geometry/Shape/D3/Prism.php b/Math/Geometry/Shape/D3/Prism.php
index fd59da23a..f09576dc8 100644
--- a/Math/Geometry/Shape/D3/Prism.php
+++ b/Math/Geometry/Shape/D3/Prism.php
@@ -13,7 +13,7 @@
 declare(strict_types=1);
 namespace phpOMS\Math\Geometry\Shape\D3;
 
-class Prism implements D3ShapeInterface
+final class Prism implements D3ShapeInterface
 {
 
 }
diff --git a/Math/Geometry/Shape/D3/RectangularPyramid.php b/Math/Geometry/Shape/D3/RectangularPyramid.php
index 385410e88..a14f24909 100644
--- a/Math/Geometry/Shape/D3/RectangularPyramid.php
+++ b/Math/Geometry/Shape/D3/RectangularPyramid.php
@@ -22,7 +22,7 @@ namespace phpOMS\Math\Geometry\Shape\D3;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class RectangularPyramid implements D3ShapeInterface
+final class RectangularPyramid implements D3ShapeInterface
 {
 
     /**
diff --git a/Math/Geometry/Shape/D3/Sphere.php b/Math/Geometry/Shape/D3/Sphere.php
index 9516d9053..4ebab7b85 100644
--- a/Math/Geometry/Shape/D3/Sphere.php
+++ b/Math/Geometry/Shape/D3/Sphere.php
@@ -22,7 +22,7 @@ namespace phpOMS\Math\Geometry\Shape\D3;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class Sphere implements D3ShapeInterface
+final class Sphere implements D3ShapeInterface
 {
     /**
      * Radius.
diff --git a/Math/Geometry/Shape/D3/Tetrahedron.php b/Math/Geometry/Shape/D3/Tetrahedron.php
index 2baa9e45a..70ce08e6d 100644
--- a/Math/Geometry/Shape/D3/Tetrahedron.php
+++ b/Math/Geometry/Shape/D3/Tetrahedron.php
@@ -22,7 +22,7 @@ namespace phpOMS\Math\Geometry\Shape\D3;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class Tetrahedron implements D3ShapeInterface
+final class Tetrahedron implements D3ShapeInterface
 {
 
     /**
diff --git a/Math/Matrix/CholeskyDecomposition.php b/Math/Matrix/CholeskyDecomposition.php
index 6769a7e22..e78a6e082 100644
--- a/Math/Matrix/CholeskyDecomposition.php
+++ b/Math/Matrix/CholeskyDecomposition.php
@@ -24,7 +24,7 @@ use phpOMS\Math\Matrix\Exception\InvalidDimensionException;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class CholeskyDecomposition
+final class CholeskyDecomposition
 {
     /**
      * L matrix.
diff --git a/Math/Matrix/EigenvalueDecomposition.php b/Math/Matrix/EigenvalueDecomposition.php
index 981f746c6..12281785e 100644
--- a/Math/Matrix/EigenvalueDecomposition.php
+++ b/Math/Matrix/EigenvalueDecomposition.php
@@ -22,6 +22,6 @@ namespace phpOMS\Math\Matrix;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class EigenValueDecomposition
+final class EigenValueDecomposition
 {
 }
diff --git a/Math/Matrix/Exception/InvalidDimensionException.php b/Math/Matrix/Exception/InvalidDimensionException.php
index 7cb05267d..02228184a 100644
--- a/Math/Matrix/Exception/InvalidDimensionException.php
+++ b/Math/Matrix/Exception/InvalidDimensionException.php
@@ -22,7 +22,7 @@ namespace phpOMS\Math\Matrix\Exception;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class InvalidDimensionException extends \UnexpectedValueException
+final class InvalidDimensionException extends \UnexpectedValueException
 {
     /**
      * Constructor.
diff --git a/Math/Matrix/IdentityMatrix.php b/Math/Matrix/IdentityMatrix.php
index 574ab6d8c..e593eb1a2 100644
--- a/Math/Matrix/IdentityMatrix.php
+++ b/Math/Matrix/IdentityMatrix.php
@@ -22,7 +22,7 @@ namespace phpOMS\Math\Matrix;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class IdentityMatrix extends Matrix
+final class IdentityMatrix extends Matrix
 {
     /**
      * Constructor.
diff --git a/Math/Matrix/LUDecomposition.php b/Math/Matrix/LUDecomposition.php
index c0789f08d..575b1c20f 100644
--- a/Math/Matrix/LUDecomposition.php
+++ b/Math/Matrix/LUDecomposition.php
@@ -24,7 +24,7 @@ use phpOMS\Math\Matrix\Exception\InvalidDimensionException;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class LUDecomposition
+final class LUDecomposition
 {
     /**
      * LU matrix.
diff --git a/Math/Matrix/QRDecomposition.php b/Math/Matrix/QRDecomposition.php
index 539755926..8677ee381 100644
--- a/Math/Matrix/QRDecomposition.php
+++ b/Math/Matrix/QRDecomposition.php
@@ -22,7 +22,7 @@ namespace phpOMS\Math\Matrix;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class QRDecomposition
+final class QRDecomposition
 {
     private $QR = [];
 
diff --git a/Math/Matrix/SingularValueDecomposition.php b/Math/Matrix/SingularValueDecomposition.php
index e47e694b5..b96a13157 100644
--- a/Math/Matrix/SingularValueDecomposition.php
+++ b/Math/Matrix/SingularValueDecomposition.php
@@ -22,6 +22,6 @@ namespace phpOMS\Math\Matrix;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class SingularValueDecomposition
+final class SingularValueDecomposition
 {
 }
diff --git a/Math/Matrix/Vector.php b/Math/Matrix/Vector.php
index e9b570235..d6e2fe224 100644
--- a/Math/Matrix/Vector.php
+++ b/Math/Matrix/Vector.php
@@ -22,6 +22,6 @@ namespace phpOMS\Math\Matrix;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class Vector extends Matrix
+final class Vector extends Matrix
 {
 }
diff --git a/Math/Number/Complex.php b/Math/Number/Complex.php
index 6852ca032..dd27625e0 100644
--- a/Math/Number/Complex.php
+++ b/Math/Number/Complex.php
@@ -22,7 +22,7 @@ namespace phpOMS\Math\Number;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class Complex
+final class Complex
 {
     /**
      * Real part.
diff --git a/Math/Number/Integer.php b/Math/Number/Integer.php
index 9d2fc5f61..2b958e8e5 100644
--- a/Math/Number/Integer.php
+++ b/Math/Number/Integer.php
@@ -22,8 +22,19 @@ namespace phpOMS\Math\Number;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class Integer
+final class Integer
 {
+    /**
+     * Constructor.
+     *
+     * @since  1.0.0
+     * @codeCoverageIgnore
+     */
+    private function __construct()
+    {
+
+    }
+    
     /**
      * Is integer.
      *
diff --git a/Math/Number/Natural.php b/Math/Number/Natural.php
index d9ea2d009..712bae656 100644
--- a/Math/Number/Natural.php
+++ b/Math/Number/Natural.php
@@ -22,8 +22,19 @@ namespace phpOMS\Math\Number;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class Natural
+final class Natural
 {
+    /**
+     * Constructor.
+     *
+     * @since  1.0.0
+     * @codeCoverageIgnore
+     */
+    private function __construct()
+    {
+
+    }
+    
     /**
      * Is natural number.
      *
diff --git a/Math/Number/Numbers.php b/Math/Number/Numbers.php
index 4d88c13d9..bd18fd112 100644
--- a/Math/Number/Numbers.php
+++ b/Math/Number/Numbers.php
@@ -22,8 +22,19 @@ namespace phpOMS\Math\Number;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class Numbers
+final class Numbers
 {
+    /**
+     * Constructor.
+     *
+     * @since  1.0.0
+     * @codeCoverageIgnore
+     */
+    private function __construct()
+    {
+
+    }
+    
     /**
      * Is perfect number?
      *
diff --git a/Math/Number/Prime.php b/Math/Number/Prime.php
index a1f56708a..f252d1d99 100644
--- a/Math/Number/Prime.php
+++ b/Math/Number/Prime.php
@@ -22,8 +22,19 @@ namespace phpOMS\Math\Number;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class Prime
+final class Prime
 {
+    /**
+     * Constructor.
+     *
+     * @since  1.0.0
+     * @codeCoverageIgnore
+     */
+    private function __construct()
+    {
+
+    }
+    
     /**
      * Is mersenne number?
      *
diff --git a/Math/Statistic/Average.php b/Math/Statistic/Average.php
index 574c93d20..1c77a471a 100644
--- a/Math/Statistic/Average.php
+++ b/Math/Statistic/Average.php
@@ -25,7 +25,7 @@ use phpOMS\Math\Matrix\Exception\InvalidDimensionException;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class Average
+final class Average
 {
 
     public const MA3    = [1 / 3, 1 / 3];
@@ -40,6 +40,17 @@ class Average
     public const MAH13  = [0.240, 0.214, 0.147, 0.66, 0, -0.028, -0.019];
     public const MAH23  = [0.148, 0.138, 0.122, 0.097, 0.068, 0.039, 0.013, -0.005, -0.015, -0.016, -0.011, -0.004];
 
+    /**
+     * Constructor.
+     *
+     * @since  1.0.0
+     * @codeCoverageIgnore
+     */
+    private function __construct()
+    {
+
+    }
+    
     /**
      * Average change.
      *
diff --git a/Math/Statistic/Basic.php b/Math/Statistic/Basic.php
index 0729cc29c..2215a233f 100644
--- a/Math/Statistic/Basic.php
+++ b/Math/Statistic/Basic.php
@@ -22,8 +22,18 @@ namespace phpOMS\Math\Statistic;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class Basic
+final class Basic
 {
+    /**
+     * Constructor.
+     *
+     * @since  1.0.0
+     * @codeCoverageIgnore
+     */
+    private function __construct()
+    {
+
+    }
 
     /**
      * Calculate frequency.
diff --git a/Math/Statistic/Correlation.php b/Math/Statistic/Correlation.php
index 4404ec949..e98f47d3f 100644
--- a/Math/Statistic/Correlation.php
+++ b/Math/Statistic/Correlation.php
@@ -22,8 +22,18 @@ namespace phpOMS\Math\Statistic;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class Correlation
+final class Correlation
 {
+    /**
+     * Constructor.
+     *
+     * @since  1.0.0
+     * @codeCoverageIgnore
+     */
+    private function __construct()
+    {
+
+    }
 
     /**
      * Calculage bravais person correlation coefficient.
diff --git a/Math/Statistic/MeasureOfDispersion.php b/Math/Statistic/MeasureOfDispersion.php
index a369c67dc..d9366898c 100644
--- a/Math/Statistic/MeasureOfDispersion.php
+++ b/Math/Statistic/MeasureOfDispersion.php
@@ -25,8 +25,18 @@ use phpOMS\Math\Matrix\Exception\InvalidDimensionException;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class MeasureOfDispersion
+final class MeasureOfDispersion
 {
+    /**
+     * Constructor.
+     *
+     * @since  1.0.0
+     * @codeCoverageIgnore
+     */
+    private function __construct()
+    {
+
+    }
 
     /**
      * Get range.
diff --git a/Message/Http/Header.php b/Message/Http/Header.php
index 46f6908a3..49fe50695 100644
--- a/Message/Http/Header.php
+++ b/Message/Http/Header.php
@@ -27,7 +27,7 @@ use phpOMS\DataStorage\LockException;
  * 
  * @SuppressWarnings(PHPMD.Superglobals)
  */
-class Header extends HeaderAbstract
+final class Header extends HeaderAbstract
 {
 
     /**
diff --git a/Message/Http/Request.php b/Message/Http/Request.php
index 51dd73280..7de42d828 100644
--- a/Message/Http/Request.php
+++ b/Message/Http/Request.php
@@ -32,7 +32,7 @@ use phpOMS\Uri\UriInterface;
  * 
  * @SuppressWarnings(PHPMD.Superglobals)
  */
-class Request extends RequestAbstract
+final class Request extends RequestAbstract
 {
 
     /**
diff --git a/Message/Http/Response.php b/Message/Http/Response.php
index 7134c987f..91bfe56b7 100644
--- a/Message/Http/Response.php
+++ b/Message/Http/Response.php
@@ -28,7 +28,7 @@ use phpOMS\Views\View;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class Response extends ResponseAbstract implements RenderableInterface
+final class Response extends ResponseAbstract implements RenderableInterface
 {
     /**
      * Response status.
diff --git a/Message/Http/Rest.php b/Message/Http/Rest.php
index ec4d0a2b3..3bc67adea 100644
--- a/Message/Http/Rest.php
+++ b/Message/Http/Rest.php
@@ -22,7 +22,7 @@ namespace phpOMS\Message\Http;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class Rest
+final class Rest
 {
 
     /**
diff --git a/Module/Exception/InvalidModuleException.php b/Module/Exception/InvalidModuleException.php
index 36bb49ddd..8bb55a1c8 100644
--- a/Module/Exception/InvalidModuleException.php
+++ b/Module/Exception/InvalidModuleException.php
@@ -22,7 +22,7 @@ namespace phpOMS\Module\Exception;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class InvalidModuleException extends \UnexpectedValueException
+final class InvalidModuleException extends \UnexpectedValueException
 {
     /**
      * Constructor.
diff --git a/Module/Exception/InvalidThemeException.php b/Module/Exception/InvalidThemeException.php
index f08416349..36e06c276 100644
--- a/Module/Exception/InvalidThemeException.php
+++ b/Module/Exception/InvalidThemeException.php
@@ -22,7 +22,7 @@ namespace phpOMS\Module\Exception;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class InvalidThemeException extends \UnexpectedValueException
+final class InvalidThemeException extends \UnexpectedValueException
 {
     /**
      * Constructor.
diff --git a/Module/InfoManager.php b/Module/InfoManager.php
index 95998fc72..261e09a13 100644
--- a/Module/InfoManager.php
+++ b/Module/InfoManager.php
@@ -27,7 +27,7 @@ use phpOMS\Utils\ArrayUtils;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class InfoManager
+final class InfoManager
 {
 
     /**
diff --git a/Module/ModuleFactory.php b/Module/ModuleFactory.php
index 3a5cac6ef..9f905dd99 100644
--- a/Module/ModuleFactory.php
+++ b/Module/ModuleFactory.php
@@ -27,7 +27,7 @@ use phpOMS\ApplicationAbstract;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class ModuleFactory
+final class ModuleFactory
 {
 
     /**
diff --git a/Module/ModuleManager.php b/Module/ModuleManager.php
index debeeb334..c77d9d235 100644
--- a/Module/ModuleManager.php
+++ b/Module/ModuleManager.php
@@ -33,7 +33,7 @@ use phpOMS\Module\Exception\InvalidModuleException;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class ModuleManager
+final class ModuleManager
 {
 
     /**
diff --git a/Module/NullModule.php b/Module/NullModule.php
index 6c7790cb4..79b5841a2 100644
--- a/Module/NullModule.php
+++ b/Module/NullModule.php
@@ -22,6 +22,6 @@ namespace phpOMS\Module;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class NullModule extends ModuleAbstract
+final class NullModule extends ModuleAbstract
 {
 }
diff --git a/Module/PackageManager.php b/Module/PackageManager.php
index 54e8fa434..039149644 100644
--- a/Module/PackageManager.php
+++ b/Module/PackageManager.php
@@ -31,7 +31,7 @@ use phpOMS\Utils\StringUtils;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class PackageManager
+final class PackageManager
 {
     /**
      * File path.
diff --git a/Router/Router.php b/Router/Router.php
index 2b9341237..f1afc3111 100644
--- a/Router/Router.php
+++ b/Router/Router.php
@@ -24,7 +24,7 @@ use phpOMS\Message\RequestAbstract;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class Router
+final class Router
 {
 
     /**
diff --git a/Security/PhpCode.php b/Security/PhpCode.php
index b9883c9ba..5b1fa21bf 100644
--- a/Security/PhpCode.php
+++ b/Security/PhpCode.php
@@ -22,7 +22,7 @@ namespace phpOMS\Security;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class PhpCode
+final class PhpCode
 {
     /**
      * Disabled functions
@@ -54,6 +54,17 @@ class PhpCode
         'posix_setuid', 'posix_uname', 'proc_close', 'proc_get_status',
     ];
 
+    /**
+     * Constructor.
+     *
+     * @since  1.0.0
+     * @codeCoverageIgnore
+     */
+    private function __construct()
+    {
+
+    }
+
     /**
      * Normalize source code for inspection
      *
diff --git a/System/File/FileUtils.php b/System/File/FileUtils.php
index 8a791ad66..cf144848d 100644
--- a/System/File/FileUtils.php
+++ b/System/File/FileUtils.php
@@ -22,7 +22,7 @@ namespace phpOMS\System\File;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class FileUtils
+final class FileUtils
 {
     public const CODE_EXTENSION         = ['cpp', 'c', 'h', 'hpp', 'cs', 'css', 'htm', 'html', 'php', 'rb'];
     public const TEXT_EXTENSION         = ['doc', 'docx', 'txt', 'md', 'csv'];
diff --git a/System/File/Local/Directory.php b/System/File/Local/Directory.php
index 2e0f76bf8..53cd51867 100644
--- a/System/File/Local/Directory.php
+++ b/System/File/Local/Directory.php
@@ -29,7 +29,7 @@ use phpOMS\Utils\StringUtils;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class Directory extends FileAbstract implements DirectoryInterface
+final class Directory extends FileAbstract implements DirectoryInterface
 {
     /**
      * Directory list filter.
diff --git a/System/File/Local/File.php b/System/File/Local/File.php
index 970e2bb2c..7abd73c8c 100644
--- a/System/File/Local/File.php
+++ b/System/File/Local/File.php
@@ -29,7 +29,7 @@ use phpOMS\System\File\PathException;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class File extends FileAbstract implements FileInterface
+final class File extends FileAbstract implements FileInterface
 {
 
     /**
diff --git a/System/File/PathException.php b/System/File/PathException.php
index aa8cede2f..713f53702 100644
--- a/System/File/PathException.php
+++ b/System/File/PathException.php
@@ -22,7 +22,7 @@ namespace phpOMS\System\File;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class PathException extends \UnexpectedValueException
+final class PathException extends \UnexpectedValueException
 {
     /**
      * Constructor.
diff --git a/System/File/PermissionException.php b/System/File/PermissionException.php
index 658532430..d5d6f1f12 100644
--- a/System/File/PermissionException.php
+++ b/System/File/PermissionException.php
@@ -22,7 +22,7 @@ namespace phpOMS\System\File;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class PermissionException extends \RuntimeException
+final class PermissionException extends \RuntimeException
 {
     /**
      * Constructor.
diff --git a/System/OperatingSystem.php b/System/OperatingSystem.php
index 4df3e6b9d..a61229d6a 100644
--- a/System/OperatingSystem.php
+++ b/System/OperatingSystem.php
@@ -24,6 +24,17 @@ namespace phpOMS\System;
  */
 final class OperatingSystem
 {
+    /**
+     * Constructor.
+     *
+     * @since  1.0.0
+     * @codeCoverageIgnore
+     */
+    private function __construct()
+    {
+
+    }
+    
     /**
      * Get OS.
      *
diff --git a/System/SystemUtils.php b/System/SystemUtils.php
index 74221a201..c0383fe92 100644
--- a/System/SystemUtils.php
+++ b/System/SystemUtils.php
@@ -22,7 +22,7 @@ namespace phpOMS\System;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class SystemUtils
+final class SystemUtils
 {
 
     /**
diff --git a/Uri/Http.php b/Uri/Http.php
index 798fbbfae..d304a73ed 100644
--- a/Uri/Http.php
+++ b/Uri/Http.php
@@ -28,7 +28,7 @@ use phpOMS\Utils\StringUtils;
  * 
  * @SuppressWarnings(PHPMD.Superglobals)
  */
-class Http implements UriInterface
+final class Http implements UriInterface
 {
 
     /**
diff --git a/Uri/UriFactory.php b/Uri/UriFactory.php
index ddfdcc3f7..cdb06cbd4 100644
--- a/Uri/UriFactory.php
+++ b/Uri/UriFactory.php
@@ -24,7 +24,7 @@ namespace phpOMS\Uri;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class UriFactory
+final class UriFactory
 {
 
     /**
diff --git a/Utils/ArrayUtils.php b/Utils/ArrayUtils.php
index f93fdfa8a..bb1eec94e 100644
--- a/Utils/ArrayUtils.php
+++ b/Utils/ArrayUtils.php
@@ -22,7 +22,7 @@ namespace phpOMS\Utils;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class ArrayUtils
+final class ArrayUtils
 {
 
     /**
diff --git a/Utils/ColorUtils.php b/Utils/ColorUtils.php
index 134c963b5..ef9b1245d 100644
--- a/Utils/ColorUtils.php
+++ b/Utils/ColorUtils.php
@@ -22,8 +22,18 @@ namespace phpOMS\Utils;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class ColorUtils
+final class ColorUtils
 {
+    /**
+     * Constructor.
+     *
+     * @since  1.0.0
+     * @codeCoverageIgnore
+     */
+    private function __construct()
+    {
+
+    }
 
     /**
      * Convert int to rgb
diff --git a/Utils/ImageUtils.php b/Utils/ImageUtils.php
index 2bb38d928..d1e82b3c0 100644
--- a/Utils/ImageUtils.php
+++ b/Utils/ImageUtils.php
@@ -24,8 +24,19 @@ namespace phpOMS\Utils;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class ImageUtils
+final class ImageUtils
 {
+    /**
+     * Constructor.
+     *
+     * @since  1.0.0
+     * @codeCoverageIgnore
+     */
+    private function __construct()
+    {
+
+    }
+
     /**
      * Decode base64 image.
      *
diff --git a/Utils/JsonBuilder.php b/Utils/JsonBuilder.php
index 5d2f4d6f0..b1c0aabc9 100644
--- a/Utils/JsonBuilder.php
+++ b/Utils/JsonBuilder.php
@@ -22,7 +22,7 @@ namespace phpOMS\Utils;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class JsonBuilder implements \Serializable, \JsonSerializable
+final class JsonBuilder implements \Serializable, \JsonSerializable
 {
 
     /**
@@ -33,15 +33,6 @@ class JsonBuilder implements \Serializable, \JsonSerializable
      */
     private $json = [];
 
-    /**
-     * Constructor.
-     *
-     * @since  1.0.0
-     */
-    public function __construct()
-    {
-    }
-
     /**
      * Get json data.
      *
diff --git a/Utils/Permutation.php b/Utils/Permutation.php
index 87b0097f2..b49dfc1b0 100644
--- a/Utils/Permutation.php
+++ b/Utils/Permutation.php
@@ -22,8 +22,19 @@ namespace phpOMS\Utils;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class Permutation
+final class Permutation
 {
+    /**
+     * Constructor.
+     *
+     * @since  1.0.0
+     * @codeCoverageIgnore
+     */
+    private function __construct()
+    {
+
+    }
+
     /**
      * Create all permutations.
      *
diff --git a/Utils/StringCompare.php b/Utils/StringCompare.php
index 9539756ca..c2a479416 100644
--- a/Utils/StringCompare.php
+++ b/Utils/StringCompare.php
@@ -24,7 +24,7 @@ namespace phpOMS\Utils;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class StringCompare
+final class StringCompare
 {
     /**
      * Dictionary.
diff --git a/Utils/StringUtils.php b/Utils/StringUtils.php
index b62961847..cedd86b13 100644
--- a/Utils/StringUtils.php
+++ b/Utils/StringUtils.php
@@ -26,7 +26,7 @@ namespace phpOMS\Utils;
  * 
  * @SuppressWarnings(PHPMD.CamelCaseMethodName)
  */
-class StringUtils
+final class StringUtils
 {
 
     /**
diff --git a/Utils/TestUtils.php b/Utils/TestUtils.php
index 2c37503f5..da6d73c9d 100644
--- a/Utils/TestUtils.php
+++ b/Utils/TestUtils.php
@@ -24,8 +24,19 @@ namespace phpOMS\Utils;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class TestUtils
+final class TestUtils
 {
+    /**
+     * Constructor.
+     *
+     * @since  1.0.0
+     * @codeCoverageIgnore
+     */
+    private function __construct()
+    {
+
+    }
+    
     /**
      * Set private object member
      *
diff --git a/Version/Version.php b/Version/Version.php
index 97c031384..5c828d13f 100644
--- a/Version/Version.php
+++ b/Version/Version.php
@@ -24,7 +24,7 @@ namespace phpOMS\Version;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class Version
+final class Version
 {
 
     /**
diff --git a/tests/Account/AccountTest.php b/tests/Account/AccountTest.php
index e9d081265..464f2e33a 100644
--- a/tests/Account/AccountTest.php
+++ b/tests/Account/AccountTest.php
@@ -65,7 +65,7 @@ class AccountTest extends \PHPUnit\Framework\TestCase
         self::assertTrue(is_int($account->getId()));
         self::assertEquals(0, $account->getId());
 
-        self::assertInstanceOf('\phpOMS\Localization\NullLocalization', $account->getL11n());
+        self::assertInstanceOf('\phpOMS\Localization\Localization', $account->getL11n());
 
         self::assertEquals([], $account->getGroups());
 
@@ -154,11 +154,8 @@ class AccountTest extends \PHPUnit\Framework\TestCase
         self::assertFalse($account->hasPermission(PermissionType::READ, 1, 'a', 1, 1, 1, 1));
         self::assertTrue($account->hasPermission(PermissionType::NONE));
 
-        $account->setL11n(new NullLocalization());
-        self::assertInstanceOf('\phpOMS\Localization\NullLocalization', $account->getL11n());
         $account->setL11n(new Localization());
         self::assertInstanceOf('\phpOMS\Localization\Localization', $account->getL11n());
-        self::assertNotInstanceOf('\phpOMS\Localization\NullLocalization', $account->getL11n());
 
         $datetime = new \DateTime('now');
         $account->updateLastActive();
diff --git a/tests/Localization/NullLocalizationTest.php b/tests/Localization/NullLocalizationTest.php
deleted file mode 100644
index 47c48386c..000000000
--- a/tests/Localization/NullLocalizationTest.php
+++ /dev/null
@@ -1,27 +0,0 @@
-<?php
-/**
- * Orange Management
- *
- * PHP Version 7.2
- *
- * @package    TBD
- * @copyright  Dennis Eichhorn
- * @license    OMS License 1.0
- * @version    1.0.0
- * @link       http://website.orange-management.de
- */
-
-namespace phpOMS\tests\Localization;
-
-require_once __DIR__ . '/../Autoloader.php';
-
-use phpOMS\Localization\NullLocalization;
-use phpOMS\Localization\Localization;
-
-class NullLocalizationTest extends \PHPUnit\Framework\TestCase
-{
-    public function testNullModel()
-    {
-        self::assertInstanceOf(Localization::class, new NullLocalization());
-    }
-}
diff --git a/tests/Utils/Parser/Markdown/data/compound_emphasis.html b/tests/Utils/Parser/Markdown/data/compound_emphasis.html
index 178dd54ba..f1b334502 100644
--- a/tests/Utils/Parser/Markdown/data/compound_emphasis.html
+++ b/tests/Utils/Parser/Markdown/data/compound_emphasis.html
@@ -1,2 +1,2 @@
-<p><em><code>code</code></em> <strong><code>code</code></strong></p>
+<p><em><code>code</code></em> <u><code>code</code></u></p>
 <p><em><code>code</code><strong><code>code</code></strong><code>code</code></em></p>
\ No newline at end of file
diff --git a/tests/Utils/Parser/Markdown/data/em_strong.html b/tests/Utils/Parser/Markdown/data/em_strong.html
index 323d60aec..c2cddc0fc 100644
--- a/tests/Utils/Parser/Markdown/data/em_strong.html
+++ b/tests/Utils/Parser/Markdown/data/em_strong.html
@@ -1,7 +1,7 @@
-<p><strong><em>em strong</em></strong></p>
-<p><strong><em>em strong</em> strong</strong></p>
-<p><strong>strong <em>em strong</em></strong></p>
-<p><strong>strong <em>em strong</em> strong</strong></p>
+<p><u><em>em strong</em></u></p>
+<p><u><em>em strong</em> strong</u></p>
+<p><u>strong <em>em strong</em></u></p>
+<p><u>strong <em>em strong</em> strong</u></p>
 <p><strong><em>em strong</em></strong></p>
 <p><strong><em>em strong</em> strong</strong></p>
 <p><strong>strong <em>em strong</em></strong></p>
diff --git a/tests/Utils/Parser/Markdown/data/escaping.html b/tests/Utils/Parser/Markdown/data/escaping.html
index ab1c41fdc..06b4339b0 100644
--- a/tests/Utils/Parser/Markdown/data/escaping.html
+++ b/tests/Utils/Parser/Markdown/data/escaping.html
@@ -2,5 +2,5 @@
 <p><code>escaped \*emphasis\* in a code span</code></p>
 <pre><code>escaped \*emphasis\* in a code block</code></pre>
 <p>\ ` * _ { } [ ] ( ) > # + - . !</p>
-<p><em>one_two</em> <strong>one_two</strong></p>
+<p><em>one_two</em> <u>one_two</u></p>
 <p><em>one*two</em> <strong>one*two</strong></p>
\ No newline at end of file
diff --git a/tests/Utils/Parser/Markdown/data/strong_em.html b/tests/Utils/Parser/Markdown/data/strong_em.html
index b709c9914..4ae9392bd 100644
--- a/tests/Utils/Parser/Markdown/data/strong_em.html
+++ b/tests/Utils/Parser/Markdown/data/strong_em.html
@@ -1,6 +1,6 @@
 <p><em>em <strong>strong em</strong></em></p>
 <p><em><strong>strong em</strong> em</em></p>
 <p><em>em <strong>strong em</strong> em</em></p>
-<p><em>em <strong>strong em</strong></em></p>
-<p><em><strong>strong em</strong> em</em></p>
-<p><em>em <strong>strong em</strong> em</em></p>
\ No newline at end of file
+<p><em>em <u>strong em</u></em></p>
+<p><em><u>strong em</u> em</em></p>
+<p><em>em <u>strong em</u> em</em></p>
\ No newline at end of file