diff --git a/composer.lock b/composer.lock
index 322a6bc9..47067177 100644
--- a/composer.lock
+++ b/composer.lock
@@ -4955,16 +4955,16 @@
         },
         {
             "name": "symfony/http-client-contracts",
-            "version": "v1.1.7",
+            "version": "v1.1.8",
             "source": {
                 "type": "git",
                 "url": "https://github.com/symfony/http-client-contracts.git",
-                "reference": "353b2a3e907e5c34cf8f74827a4b21eb745aab1d"
+                "reference": "088bae75cfa2ec5eb6d33dce17dbd8613150ce6e"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/symfony/http-client-contracts/zipball/353b2a3e907e5c34cf8f74827a4b21eb745aab1d",
-                "reference": "353b2a3e907e5c34cf8f74827a4b21eb745aab1d",
+                "url": "https://api.github.com/repos/symfony/http-client-contracts/zipball/088bae75cfa2ec5eb6d33dce17dbd8613150ce6e",
+                "reference": "088bae75cfa2ec5eb6d33dce17dbd8613150ce6e",
                 "shasum": ""
             },
             "require": {
@@ -5008,7 +5008,7 @@
                 "interoperability",
                 "standards"
             ],
-            "time": "2019-09-26T22:09:58+00:00"
+            "time": "2019-11-07T12:44:51+00:00"
         },
         {
             "name": "symfony/http-foundation",
@@ -6566,16 +6566,16 @@
         },
         {
             "name": "symfony/service-contracts",
-            "version": "v1.1.7",
+            "version": "v1.1.8",
             "source": {
                 "type": "git",
                 "url": "https://github.com/symfony/service-contracts.git",
-                "reference": "ffcde9615dc5bb4825b9f6aed07716f1f57faae0"
+                "reference": "ffc7f5692092df31515df2a5ecf3b7302b3ddacf"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/symfony/service-contracts/zipball/ffcde9615dc5bb4825b9f6aed07716f1f57faae0",
-                "reference": "ffcde9615dc5bb4825b9f6aed07716f1f57faae0",
+                "url": "https://api.github.com/repos/symfony/service-contracts/zipball/ffc7f5692092df31515df2a5ecf3b7302b3ddacf",
+                "reference": "ffc7f5692092df31515df2a5ecf3b7302b3ddacf",
                 "shasum": ""
             },
             "require": {
@@ -6620,7 +6620,7 @@
                 "interoperability",
                 "standards"
             ],
-            "time": "2019-09-17T11:12:18+00:00"
+            "time": "2019-10-14T12:27:06+00:00"
         },
         {
             "name": "symfony/stopwatch",
diff --git a/src/Controller/AdminPages/BaseAdminController.php b/src/Controller/AdminPages/BaseAdminController.php
index fe545f1e..f2901087 100644
--- a/src/Controller/AdminPages/BaseAdminController.php
+++ b/src/Controller/AdminPages/BaseAdminController.php
@@ -199,16 +199,21 @@ abstract class BaseAdminController extends AbstractController
         if ($mass_creation_form->isSubmitted() && $mass_creation_form->isValid()) {
             $data = $mass_creation_form->getData();
 
-            dump($data);
-
             //Create entries based on input
-            $errors = $importer->massCreation($data['lines'], $this->entity_class, $data['parent']);
+            $errors = [];
+            $results = $importer->massCreation($data['lines'], $this->entity_class, $data['parent'], $errors);
 
             //Show errors to user:
-            foreach ($errors as $name => $error) {
-                /* @var $error ConstraintViolationList */
-                $this->addFlash('error', $name.':'.$error);
+            foreach ($errors as $error) {
+                dump($error);
+                $this->addFlash('error', $error['entity']->getFullPath().':'.$error['violations']);
             }
+
+            //Persist valid entities to DB
+            foreach ($results as $result) {
+                $em->persist($result);
+            }
+            $em->flush();
         }
 
         return $this->render($this->twig_template, [
diff --git a/src/Services/ElementTypeNameGenerator.php b/src/Services/ElementTypeNameGenerator.php
index fba29366..275554d3 100644
--- a/src/Services/ElementTypeNameGenerator.php
+++ b/src/Services/ElementTypeNameGenerator.php
@@ -111,14 +111,15 @@ class ElementTypeNameGenerator
      * @param bool           $use_html If set to true, a html string is returned, where the type is set italic
      *
      * @return string The localized string
+     * @throws EntityNotSupportedException When the passed entity is not supported.
      */
     public function getTypeNameCombination(NamedDBElement $entity, bool $use_html = false): string
     {
         $type = $this->getLocalizedTypeLabel($entity);
         if ($use_html) {
-            return '<i>'.$type.':</i> '.$entity->getName();
+            return '<i>'.$type.':</i> '.htmlspecialchars($entity->getName());
         }
 
-        return $type.': '.htmlspecialchars($entity->getName());
+        return $type.': '.$entity->getName();
     }
 }
diff --git a/src/Services/EntityImporter.php b/src/Services/EntityImporter.php
index a12b958a..0f056cb7 100644
--- a/src/Services/EntityImporter.php
+++ b/src/Services/EntityImporter.php
@@ -21,6 +21,7 @@
 
 namespace App\Services;
 
+use App\Entity\Base\DBElement;
 use App\Entity\Base\StructuralDBElement;
 use Doctrine\ORM\EntityManagerInterface;
 use Symfony\Component\HttpFoundation\File\File;
@@ -44,7 +45,7 @@ class EntityImporter
     protected function configureOptions(OptionsResolver $resolver)
     {
         $resolver->setDefaults([
-           'csv_separator' => ';',
+            'csv_separator' => ';',
             'format' => 'json',
             'preserve_children' => true,
             'parent' => null,
@@ -53,24 +54,37 @@ class EntityImporter
     }
 
     /**
-     * Creates many entries at once, based on a (text) list of names.
+     * Creates many entries at once, based on a (text) list of name.
+     * The created enties are not persisted to database yet, so you have to do it yourself.
      *
      * @param string                   $lines      The list of names seperated by \n
      * @param string                   $class_name The name of the class for which the entities should be created
      * @param StructuralDBElement|null $parent     The element which will be used as parent element for new elements.
+     * @param array                    $errors     An associative array containing all validation errors.
      *
-     * @return array An associative array containing an ConstraintViolationList and the entity name as key are returned,
-     *               if an error happened during validation. When everything was successfull, the array should be empty.
+     * @return StructuralDBElement[]  An array containing all valid imported entities (with the type $class_name)
      */
-    public function massCreation(string $lines, string $class_name, ?StructuralDBElement $parent): array
+    public function massCreation(string $lines, string $class_name, ?StructuralDBElement $parent = null, array &$errors = []): array
     {
         //Expand every line to a single entry:
         $names = explode("\n", $lines);
 
+        if (!is_a($class_name, StructuralDBElement::class, true)) {
+            throw new \InvalidArgumentException('$class_name must be a StructuralDBElement type!');
+        }
+        if ($parent !== null && !is_a($parent, $class_name)) {
+            throw new \InvalidArgumentException('$parent must have the same type as specified in $class_name!');
+        }
+
         $errors = [];
+        $valid_entities = [];
 
         foreach ($names as $name) {
             $name = trim($name);
+            if ($name === '') {
+                //Skip empty lines (StrucuralDBElements must have a name)
+                continue;
+            }
             /** @var $entity StructuralDBElement */
             //Create new element with given name
             $entity = new $class_name();
@@ -81,17 +95,13 @@ class EntityImporter
             $tmp = $this->validator->validate($entity);
             //If no error occured, write entry to DB:
             if (0 === \count($tmp)) {
-                $this->em->persist($entity);
+                $valid_entities[] = $entity;
             } else { //Otherwise log error
-                dump($tmp);
-                $errors[$entity->getFullPath()] = $tmp;
+                $errors[] = ['entity' => $entity, 'violations' => $tmp];
             }
         }
 
-        //Save changes to database
-        $this->em->flush();
-
-        return $errors;
+        return $valid_entities;
     }
 
     /**
diff --git a/tests/Services/ElementTypeNameGeneratorTest.php b/tests/Services/ElementTypeNameGeneratorTest.php
new file mode 100644
index 00000000..12b2b968
--- /dev/null
+++ b/tests/Services/ElementTypeNameGeneratorTest.php
@@ -0,0 +1,89 @@
+<?php
+/**
+ * This file is part of Part-DB (https://github.com/Part-DB/Part-DB-symfony).
+ *
+ * Copyright (C) 2019 Jan Böhmer (https://github.com/jbtronics)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
+ */
+
+namespace App\Tests\Services;
+
+
+use App\Entity\Attachments\PartAttachment;
+use App\Entity\Base\DBElement;
+use App\Entity\Base\NamedDBElement;
+use App\Entity\Parts\Category;
+use App\Entity\Parts\Part;
+use App\Exceptions\EntityNotSupportedException;
+use App\Services\AmountFormatter;
+use App\Services\ElementTypeNameGenerator;
+use PHPUnit\Framework\TestCase;
+use Symfony\Bundle\FrameworkBundle\Test\WebTestCase;
+
+class ElementTypeNameGeneratorTest extends WebTestCase
+{
+    /**
+     * @var AmountFormatter
+     */
+    protected $service;
+
+    public function setUp()
+    {
+        parent::setUp();
+
+        //Get an service instance.
+        self::bootKernel();
+        $this->service = self::$container->get(ElementTypeNameGenerator::class);
+    }
+
+    public function testGetLocalizedTypeNameCombination()
+    {
+        //We only test in english
+        $this->assertEquals('Part', $this->service->getLocalizedTypeLabel(new Part()));
+        $this->assertEquals('Category', $this->service->getLocalizedTypeLabel(new Category()));
+
+        //Test inheritance
+        $this->assertEquals('Attachment', $this->service->getLocalizedTypeLabel(new PartAttachment()));
+
+        //Test exception for unknpwn type
+        $this->expectException(EntityNotSupportedException::class);
+        $this->service->getLocalizedTypeLabel(new class extends DBElement {
+            public function getIDString(): string
+            {
+                return 'Stub';
+            }
+        });
+    }
+
+    public function testGetTypeNameCombination()
+    {
+        $part = new Part();
+        $part->setName('Test<Part');
+        //When the text version is used, dont escape the name
+        $this->assertEquals('Part: Test<Part', $this->service->getTypeNameCombination($part, false));
+
+        $this->assertEquals('<i>Part:</i> Test&lt;Part', $this->service->getTypeNameCombination($part, true));
+
+        //Test exception
+        $this->expectException(EntityNotSupportedException::class);
+        $this->service->getTypeNameCombination(new class extends NamedDBElement {
+            public function getIDString(): string
+            {
+                return 'Stub';
+            }
+        });
+    }
+}
\ No newline at end of file
diff --git a/tests/Services/EntityImporterTest.php b/tests/Services/EntityImporterTest.php
new file mode 100644
index 00000000..36a4912c
--- /dev/null
+++ b/tests/Services/EntityImporterTest.php
@@ -0,0 +1,84 @@
+<?php
+/**
+ * This file is part of Part-DB (https://github.com/Part-DB/Part-DB-symfony).
+ *
+ * Copyright (C) 2019 Jan Böhmer (https://github.com/jbtronics)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
+ */
+
+namespace App\Tests\Services;
+
+
+use App\Entity\Attachments\AttachmentType;
+use App\Services\AmountFormatter;
+use App\Services\ElementTypeNameGenerator;
+use App\Services\EntityImporter;
+use Symfony\Bundle\FrameworkBundle\Test\WebTestCase;
+
+class EntityImporterTest extends WebTestCase
+{
+    /**
+     * @var AmountFormatter
+     */
+    protected $service;
+
+    public function setUp()
+    {
+        parent::setUp();
+
+        //Get an service instance.
+        self::bootKernel();
+        $this->service = self::$container->get(EntityImporter::class);
+    }
+
+    public function testMassCreationResults()
+    {
+        $errors = [];
+        $results = $this->service->massCreation('', AttachmentType::class, null, $errors);
+        $this->assertEmpty($results);
+        $this->assertEmpty($errors);
+
+        $errors = [];
+        $lines = "Test 1 \n Test 2 \n Test 3";
+        $results = $this->service->massCreation($lines, AttachmentType::class, null, $errors);
+        $this->assertCount(0, $errors);
+        $this->assertCount(3, $results);
+        //Check type
+        $this->assertInstanceOf(AttachmentType::class, $results[0]);
+        //Check names
+        $this->assertEquals('Test 1', $results[0]->getName());
+        $this->assertEquals('Test 2', $results[1]->getName());
+        //Check parent
+        $this->assertNull($results[0]->getMasterPictureAttachment());
+
+        $parent = new AttachmentType();
+        $results = $this->service->massCreation($lines, AttachmentType::class, $parent, $errors);
+        $this->assertCount(3, $results);
+        $this->assertEquals($parent, $results[0]->getParent());
+    }
+
+    public function testMassCreationErrors()
+    {
+        $errors = [];
+        //Node 1 and Node 2 are created in datafixtures, so their attemp to create them again must fail.
+        $lines = "Test 1 \n Node 1 \n Node 2";
+        $results = $this->service->massCreation($lines, AttachmentType::class, null, $errors);
+        $this->assertCount(1, $results);
+        $this->assertEquals('Test 1', $results[0]->getName());
+        $this->assertCount(2, $errors);
+        $this->assertEquals('Node 1', $errors[0]['entity']->getName());
+    }
+}
\ No newline at end of file