diff --git a/application/symfony/src/Domain/SourceManagement/SourceClassInformationService.php b/application/symfony/src/Domain/SourceManagement/SourceClassInformationService.php
new file mode 100644
index 0000000..3b38f44
--- /dev/null
+++ b/application/symfony/src/Domain/SourceManagement/SourceClassInformationService.php
@@ -0,0 +1,132 @@
+<?php
+
+namespace App\Domain\SourceManagement;
+
+/**
+ * @author kevinfrantz
+ */
+final class SourceClassInformationService implements SourceClassInformationServiceInterface
+{
+    /**
+     * @var string Folder with the source entities
+     */
+    const FOLDER = __DIR__.'/../../Entity/Source';
+
+    /**
+     * @var string Namespace praefix for sources
+     */
+    const SOURCE_CLASS_NAMESPACE = 'App\\Entity\\Source';
+
+    /**
+     * @var string Suffix to identifie php files
+     */
+    const PHP_SUFFIX = '.php';
+
+    /**
+     * @var string Suffix to identify interfaces
+     */
+    const INTERFACE_SUFFIX = 'Interface'.self::PHP_SUFFIX;
+
+    /**
+     * @var string[]|array Containes all source classes
+     */
+    private $allClasses = [];
+
+    /**
+     * @param string $path
+     *
+     * @return bool
+     */
+    private function isPHP(string $path): bool
+    {
+        return self::PHP_SUFFIX === substr($path, -strlen(self::PHP_SUFFIX));
+    }
+
+    /**
+     * @param string $path
+     *
+     * @return bool
+     */
+    private function isInterface(string $path): bool
+    {
+        return self::INTERFACE_SUFFIX === substr($path, -strlen(self::INTERFACE_SUFFIX));
+    }
+
+    /**
+     * @param string $path
+     *
+     * @return string
+     */
+    private function transformPathToClass(string $path): string
+    {
+        $withoutSuffix = str_replace(self::PHP_SUFFIX, '', $path);
+        $withoutFolder = str_replace(self::FOLDER, '', $withoutSuffix);
+        $class = str_replace('/', '\\', $withoutFolder);
+        $fullclass = self::SOURCE_CLASS_NAMESPACE.$class;
+
+        return $fullclass;
+    }
+
+    /**
+     * @param string $path
+     */
+    private function addToClasses(string $path): void
+    {
+        $this->allClasses[] = $this->transformPathToClass($path);
+    }
+
+    private function loadClasses()
+    {
+        $recursiveDirectoryIterator = new \RecursiveDirectoryIterator(self::FOLDER);
+        $files = new \RecursiveIteratorIterator($recursiveDirectoryIterator, \RecursiveIteratorIterator::SELF_FIRST);
+        foreach ($files as $file) {
+            $path = $file->getPathname();
+            if ($this->isPHP($path) && !$this->isInterface($path)) {
+                $this->addToClasses($path);
+            }
+        }
+    }
+
+    public function __construct()
+    {
+        $this->loadClasses();
+    }
+
+    /**
+     * @param string $subPath
+     * @param string $rootPath
+     *
+     * @return bool
+     */
+    private function isSubSourceClass(string $subPath, string $rootPath): bool
+    {
+        return substr($rootPath, 0, strlen($subPath)) === $subPath;
+    }
+
+    /**
+     * {@inheritdoc}
+     *
+     * @see \App\Domain\SourceManagement\SourceClassInformationServiceInterface::getAllSourceClasses()
+     */
+    public function getAllSourceClasses(): array
+    {
+        return $this->allClasses;
+    }
+
+    /**
+     * {@inheritdoc}
+     *
+     * @see \App\Domain\SourceManagement\SourceClassInformationServiceInterface::getAllSubSourceClasses()
+     */
+    public function getAllSubSourceClasses(string $subNamespace): array
+    {
+        $subSourceClasses = [];
+        foreach ($this->allClasses as $class) {
+            if ($this->isSubSourceClass($subNamespace, $class)) {
+                $subSourceClasses[] = $class;
+            }
+        }
+
+        return $subSourceClasses;
+    }
+}
diff --git a/application/symfony/src/Domain/SourceManagement/SourceClassInformationServiceInterface.php b/application/symfony/src/Domain/SourceManagement/SourceClassInformationServiceInterface.php
new file mode 100644
index 0000000..33eae96
--- /dev/null
+++ b/application/symfony/src/Domain/SourceManagement/SourceClassInformationServiceInterface.php
@@ -0,0 +1,23 @@
+<?php
+
+namespace App\Domain\SourceManagement;
+
+/**
+ * Offers informations about the source classes.
+ *
+ * @author kevinfrantz
+ */
+interface SourceClassInformationServiceInterface
+{
+    /**
+     * @return array|string[] Returns all source classes
+     */
+    public function getAllSourceClasses(): array;
+
+    /**
+     * @param string $subNamespace The subpath of the classes
+     *
+     * @return array|string[] Returns all source classes of a subfolder
+     */
+    public function getAllSubSourceClasses(string $subNamespace): array;
+}
diff --git a/application/symfony/tests/Unit/Domain/SourceManagement/SourceClassInformationServiceTest.php b/application/symfony/tests/Unit/Domain/SourceManagement/SourceClassInformationServiceTest.php
new file mode 100644
index 0000000..8a9e4f1
--- /dev/null
+++ b/application/symfony/tests/Unit/Domain/SourceManagement/SourceClassInformationServiceTest.php
@@ -0,0 +1,44 @@
+<?php
+
+namespace tests\Unit\Domain\SourceManagement;
+
+use App\Domain\SourceManagement\SourceClassInformationServiceInterface;
+use App\Domain\SourceManagement\SourceClassInformationService;
+use PHPUnit\Framework\TestCase;
+use App\Entity\Source\PureSource;
+use App\Entity\Source\Complex\AbstractComplexSource;
+
+/**
+ * @author kevinfrantz
+ */
+class SourceClassInformationServiceTest extends TestCase
+{
+    /**
+     * @var SourceClassInformationServiceInterface
+     */
+    private $sourceClassInformationService;
+
+    public function setUp(): void
+    {
+        $this->sourceClassInformationService = new SourceClassInformationService();
+    }
+
+    public function testPureSource(): void
+    {
+        $allClasses = $this->sourceClassInformationService->getAllSourceClasses();
+        $this->assertTrue(in_array(PureSource::class, $allClasses));
+    }
+
+    public function testNotSource(): void
+    {
+        $allClasses = $this->sourceClassInformationService->getAllSourceClasses();
+        $this->assertFalse(in_array('ALLALALABBBB', $allClasses));
+    }
+
+    public function testSubSource(): void
+    {
+        $allClasses = $this->sourceClassInformationService->getAllSubSourceClasses('App\\Entity\\Source\\Complex');
+        $this->assertFalse(in_array(PureSource::class, $allClasses));
+        $this->assertTrue(in_array(AbstractComplexSource::class, $allClasses));
+    }
+}