diff --git a/composer.json b/composer.json
index fbee068..8fc5224 100644
--- a/composer.json
+++ b/composer.json
@@ -26,6 +26,7 @@
     "beberlei/assert": "^3.3"
   },
   "require-dev": {
+    "d3/testingtools": "^1.0",
     "phpunit/phpunit": "^9.6"
   },
   "autoload": {
diff --git a/tests/unit/autoload/functions_oxDICTest.php b/tests/unit/autoload/functions_oxDICTest.php
index 7f5b0eb..674eefe 100644
--- a/tests/unit/autoload/functions_oxDICTest.php
+++ b/tests/unit/autoload/functions_oxDICTest.php
@@ -15,16 +15,19 @@ declare(strict_types=1);
 
 namespace D3\DIContainerHandler\tests\autoload;
 
+use D3\TestingTools\Development\CanAccessRestricted;
+use Exception;
 use PHPUnit\Framework\TestCase;
-use ReflectionClass;
-use ReflectionException;
 use Symfony\Component\DependencyInjection\ContainerBuilder;
 
 class functions_oxDICTest extends TestCase
 {
+    use CanAccessRestricted;
+
     /**
      * @test
      * @return void
+     * @throws Exception
      */
     public function d3GetOxidDICTest(): void
     {
@@ -33,92 +36,4 @@ class functions_oxDICTest extends TestCase
             d3GetOxidDIC()
         );
     }
-
-    /**************/
-
-
-
-    /**
-     * Calls a private or protected object method.
-     *
-     * @param object $object
-     * @param string $methodName
-     * @param array $arguments
-     *
-     * @return mixed
-     * @throws ReflectionException
-     */
-    public function callMethod($object, $methodName, array $arguments = [])
-    {
-        $class = new ReflectionClass($object);
-        $method = $class->getMethod($methodName);
-        $method->setAccessible(true);
-        return $method->invokeArgs($object, $arguments);
-    }
-
-    /**
-     * Sets a private or protected property in defined class instance
-     *
-     * @param object $object
-     * @param string $valueName
-     * @param mixed $value
-     * @throws ReflectionException
-     */
-    public function setValue($object, $valueName, $value)
-    {
-        $reflection = new ReflectionClass($object);
-        $property = $reflection->getProperty($valueName);
-        $property->setAccessible(true);
-        $property->setValue($object, $value);
-    }
-
-    /**
-     * Sets a private or protected property in mocked class instance based on original class
-     * (required for e.g. final properties, which aren't contained in mock, but in original class)
-     * @param $mockedClassName  * FQNS of original class
-     * @param $object           * mock object
-     * @param $valueName        * property name
-     * @param $value            * new property value
-     *
-     * @throws ReflectionException
-     */
-    public function setMockedClassValue($mockedClassName, $object, $valueName, $value)
-    {
-        $property = new \ReflectionProperty($mockedClassName, $valueName);
-        $property->setAccessible(true);
-        $property->setValue($object, $value);
-    }
-
-    /**
-     * get a private or protected property from defined class instance
-     *
-     * @param object $object
-     * @param string $valueName
-     * @param mixed $value
-     * @return mixed
-     * @throws ReflectionException
-     */
-    public function getValue($object, $valueName)
-    {
-        $reflection = new ReflectionClass($object);
-        $property = $reflection->getProperty($valueName);
-        $property->setAccessible(true);
-        return $property->getValue($object);
-    }
-
-    /**
-     * get a private or protected property from mocked class instance based on original class
-     * (required for e.g. final properties, which aren't contained in mock, but in original class)
-     * @param object $object
-     * @param string $valueName
-     * @param mixed $value
-     * @return mixed
-     * @throws ReflectionException
-     */
-    public function getMockedClassValue($mockedClassName, $object, $valueName)
-    {
-        $property = new \ReflectionProperty($mockedClassName, $valueName);
-        $property->setAccessible(true);
-        return $property->getValue($object);
-    }
-}
\ No newline at end of file
+}
diff --git a/tests/unit/d3DicHandlerTest.php b/tests/unit/d3DicHandlerTest.php
index 15cabdf..9a5989e 100644
--- a/tests/unit/d3DicHandlerTest.php
+++ b/tests/unit/d3DicHandlerTest.php
@@ -16,12 +16,12 @@ declare(strict_types=1);
 namespace D3\DIContainerHandler\tests;
 
 use D3\DIContainerHandler\d3DicHandler;
+use D3\TestingTools\Development\CanAccessRestricted;
 use d3DIContainerCache;
 use Generator;
 use OxidEsales\Eshop\Core\Config;
 use PHPUnit\Framework\MockObject\MockObject;
 use PHPUnit\Framework\TestCase;
-use ReflectionClass;
 use ReflectionException;
 use Symfony\Component\DependencyInjection\ContainerBuilder;
 use Symfony\Component\DependencyInjection\Loader\YamlFileLoader;
@@ -30,6 +30,8 @@ define('D3_MODCFG_TEST', true);
 
 class d3DicHandlerTest extends TestCase
 {
+    use CanAccessRestricted;
+
     /**
      * @test
      * @return void
@@ -368,92 +370,4 @@ class d3DicHandlerTest extends TestCase
             )
         );
     }
-
-    /**************/
-
-
-
-    /**
-     * Calls a private or protected object method.
-     *
-     * @param object $object
-     * @param string $methodName
-     * @param array $arguments
-     *
-     * @return mixed
-     * @throws ReflectionException
-     */
-    public function callMethod($object, $methodName, array $arguments = [])
-    {
-        $class = new ReflectionClass($object);
-        $method = $class->getMethod($methodName);
-        $method->setAccessible(true);
-        return $method->invokeArgs($object, $arguments);
-    }
-
-    /**
-     * Sets a private or protected property in defined class instance
-     *
-     * @param object $object
-     * @param string $valueName
-     * @param mixed $value
-     * @throws ReflectionException
-     */
-    public function setValue($object, $valueName, $value)
-    {
-        $reflection = new ReflectionClass($object);
-        $property = $reflection->getProperty($valueName);
-        $property->setAccessible(true);
-        $property->setValue($object, $value);
-    }
-
-    /**
-     * Sets a private or protected property in mocked class instance based on original class
-     * (required for e.g. final properties, which aren't contained in mock, but in original class)
-     * @param $mockedClassName  * FQNS of original class
-     * @param $object           * mock object
-     * @param $valueName        * property name
-     * @param $value            * new property value
-     *
-     * @throws ReflectionException
-     */
-    public function setMockedClassValue($mockedClassName, $object, $valueName, $value)
-    {
-        $property = new \ReflectionProperty($mockedClassName, $valueName);
-        $property->setAccessible(true);
-        $property->setValue($object, $value);
-    }
-
-    /**
-     * get a private or protected property from defined class instance
-     *
-     * @param object $object
-     * @param string $valueName
-     * @param mixed $value
-     * @return mixed
-     * @throws ReflectionException
-     */
-    public function getValue($object, $valueName)
-    {
-        $reflection = new ReflectionClass($object);
-        $property = $reflection->getProperty($valueName);
-        $property->setAccessible(true);
-        return $property->getValue($object);
-    }
-
-    /**
-     * get a private or protected property from mocked class instance based on original class
-     * (required for e.g. final properties, which aren't contained in mock, but in original class)
-     * @param object $object
-     * @param string $valueName
-     * @param mixed $value
-     * @return mixed
-     * @throws ReflectionException
-     */
-    public function getMockedClassValue($mockedClassName, $object, $valueName)
-    {
-        $property = new \ReflectionProperty($mockedClassName, $valueName);
-        $property->setAccessible(true);
-        return $property->getValue($object);
-    }
-}
\ No newline at end of file
+}
diff --git a/tests/unit/d3DicUtilitiesTest.php b/tests/unit/d3DicUtilitiesTest.php
index 368afed..bcb0051 100644
--- a/tests/unit/d3DicUtilitiesTest.php
+++ b/tests/unit/d3DicUtilitiesTest.php
@@ -17,13 +17,15 @@ namespace D3\DIContainerHandler\tests;
 
 use D3\DIContainerHandler\d3DicHandler;
 use D3\DIContainerHandler\d3DicUtilities;
+use D3\TestingTools\Development\CanAccessRestricted;
 use Generator;
 use PHPUnit\Framework\TestCase;
-use ReflectionClass;
 use ReflectionException;
 
 class d3DicUtilitiesTest extends TestCase
 {
+    use CanAccessRestricted;
+
     /**
      * @test
      * @param string      $className
@@ -103,92 +105,4 @@ class d3DicUtilitiesTest extends TestCase
             )
         );
     }
-
-    /**************/
-
-
-
-    /**
-     * Calls a private or protected object method.
-     *
-     * @param object $object
-     * @param string $methodName
-     * @param array $arguments
-     *
-     * @return mixed
-     * @throws ReflectionException
-     */
-    public function callMethod($object, $methodName, array $arguments = [])
-    {
-        $class = new ReflectionClass($object);
-        $method = $class->getMethod($methodName);
-        $method->setAccessible(true);
-        return $method->invokeArgs($object, $arguments);
-    }
-
-    /**
-     * Sets a private or protected property in defined class instance
-     *
-     * @param object $object
-     * @param string $valueName
-     * @param mixed $value
-     * @throws ReflectionException
-     */
-    public function setValue($object, $valueName, $value)
-    {
-        $reflection = new ReflectionClass($object);
-        $property = $reflection->getProperty($valueName);
-        $property->setAccessible(true);
-        $property->setValue($object, $value);
-    }
-
-    /**
-     * Sets a private or protected property in mocked class instance based on original class
-     * (required for e.g. final properties, which aren't contained in mock, but in original class)
-     * @param $mockedClassName  * FQNS of original class
-     * @param $object           * mock object
-     * @param $valueName        * property name
-     * @param $value            * new property value
-     *
-     * @throws ReflectionException
-     */
-    public function setMockedClassValue($mockedClassName, $object, $valueName, $value)
-    {
-        $property = new \ReflectionProperty($mockedClassName, $valueName);
-        $property->setAccessible(true);
-        $property->setValue($object, $value);
-    }
-
-    /**
-     * get a private or protected property from defined class instance
-     *
-     * @param object $object
-     * @param string $valueName
-     * @param mixed $value
-     * @return mixed
-     * @throws ReflectionException
-     */
-    public function getValue($object, $valueName)
-    {
-        $reflection = new ReflectionClass($object);
-        $property = $reflection->getProperty($valueName);
-        $property->setAccessible(true);
-        return $property->getValue($object);
-    }
-
-    /**
-     * get a private or protected property from mocked class instance based on original class
-     * (required for e.g. final properties, which aren't contained in mock, but in original class)
-     * @param object $object
-     * @param string $valueName
-     * @param mixed $value
-     * @return mixed
-     * @throws ReflectionException
-     */
-    public function getMockedClassValue($mockedClassName, $object, $valueName)
-    {
-        $property = new \ReflectionProperty($mockedClassName, $valueName);
-        $property->setAccessible(true);
-        return $property->getValue($object);
-    }
-}
\ No newline at end of file
+}
diff --git a/tests/unit/definitionFileContainerTest.php b/tests/unit/definitionFileContainerTest.php
index d06224f..9257cc4 100644
--- a/tests/unit/definitionFileContainerTest.php
+++ b/tests/unit/definitionFileContainerTest.php
@@ -17,13 +17,15 @@ namespace D3\DIContainerHandler\tests;
 
 use Assert\InvalidArgumentException;
 use D3\DIContainerHandler\definitionFileContainer;
+use D3\TestingTools\Development\CanAccessRestricted;
 use Generator;
 use PHPUnit\Framework\TestCase;
-use ReflectionClass;
 use ReflectionException;
 
 class definitionFileContainerTest extends TestCase
 {
+    use CanAccessRestricted;
+
     /**
      * @test
      *
@@ -192,93 +194,4 @@ class definitionFileContainerTest extends TestCase
             )
         );
     }
-
-
-    /**************/
-
-
-
-    /**
-     * Calls a private or protected object method.
-     *
-     * @param object $object
-     * @param string $methodName
-     * @param array $arguments
-     *
-     * @return mixed
-     * @throws ReflectionException
-     */
-    public function callMethod($object, $methodName, array $arguments = [])
-    {
-        $class = new ReflectionClass($object);
-        $method = $class->getMethod($methodName);
-        $method->setAccessible(true);
-        return $method->invokeArgs($object, $arguments);
-    }
-
-    /**
-     * Sets a private or protected property in defined class instance
-     *
-     * @param object $object
-     * @param string $valueName
-     * @param mixed $value
-     * @throws ReflectionException
-     */
-    public function setValue($object, $valueName, $value)
-    {
-        $reflection = new ReflectionClass($object);
-        $property = $reflection->getProperty($valueName);
-        $property->setAccessible(true);
-        $property->setValue($object, $value);
-    }
-
-    /**
-     * Sets a private or protected property in mocked class instance based on original class
-     * (required for e.g. final properties, which aren't contained in mock, but in original class)
-     * @param $mockedClassName  * FQNS of original class
-     * @param $object           * mock object
-     * @param $valueName        * property name
-     * @param $value            * new property value
-     *
-     * @throws ReflectionException
-     */
-    public function setMockedClassValue($mockedClassName, $object, $valueName, $value)
-    {
-        $property = new \ReflectionProperty($mockedClassName, $valueName);
-        $property->setAccessible(true);
-        $property->setValue($object, $value);
-    }
-
-    /**
-     * get a private or protected property from defined class instance
-     *
-     * @param object $object
-     * @param string $valueName
-     * @param mixed $value
-     * @return mixed
-     * @throws ReflectionException
-     */
-    public function getValue($object, $valueName)
-    {
-        $reflection = new ReflectionClass($object);
-        $property = $reflection->getProperty($valueName);
-        $property->setAccessible(true);
-        return $property->getValue($object);
-    }
-
-    /**
-     * get a private or protected property from mocked class instance based on original class
-     * (required for e.g. final properties, which aren't contained in mock, but in original class)
-     * @param object $object
-     * @param string $valueName
-     * @param mixed $value
-     * @return mixed
-     * @throws ReflectionException
-     */
-    public function getMockedClassValue($mockedClassName, $object, $valueName)
-    {
-        $property = new \ReflectionProperty($mockedClassName, $valueName);
-        $property->setAccessible(true);
-        return $property->getValue($object);
-    }
-}
\ No newline at end of file
+}