Something of namespacing the child-specific batch...

... 'cause need to slap together a media-specific batch similarly?

islandora.services.yml

@@ -60,7 +60,7 @@ services:
     tags:
       - { name: event_subscriber }
   islandora.upload_children.batch_processor:
-    class: Drupal\islandora\Form\AddChildrenWizard\BatchProcessor
+    class: Drupal\islandora\Form\AddChildrenWizard\ChildBatchProcessor
     arguments:
       - '@entity_type.manager'
       - '@database'

src/Form/AddChildrenWizard/ChildBatchProcessor.php

@@ -14,7 +14,7 @@ use Symfony\Component\HttpKernel\Exception\HttpExceptionInterface;
 /**
  * Children addition batch processor.
  */
-class BatchProcessor {
+class ChildBatchProcessor {
 
   use FieldTrait;
 
@@ -171,8 +171,8 @@ class BatchProcessor {
         foreach ($info as $id => $count) {
           $this->messenger()->addWarning($this->formatPlural(
             $count,
-            '1 validation error present in <a href=":uri">bulk created entity of type %type, with ID %id</a>.',
+            '1 validation error present in <a target="_blank" href=":uri">bulk created entity of type %type, with ID %id</a>.',
-            '@count validation errors present in <a href=":uri">bulk created entity of type %type, with ID %id</a>.',
+            '@count validation errors present in <a target="_blank" href=":uri">bulk created entity of type %type, with ID %id</a>.',
             [
               '%type' => $entity_type,
               ':uri' => Url::fromRoute("entity.{$entity_type}.canonical", [$entity_type => $id])->toString(),

src/Form/AddChildrenWizard/FileSelectionForm.php

@@ -43,9 +43,9 @@ class FileSelectionForm extends FormBase {
   /**
    * The batch processor service.
    *
-   * @var \Drupal\islandora\Form\AddChildrenWizard\BatchProcessor|null
+   * @var \Drupal\islandora\Form\AddChildrenWizard\ChildBatchProcessor|null
    */
-  protected ?BatchProcessor $batchProcessor;
+  protected ?ChildBatchProcessor $batchProcessor;
 
   /**
    * {@inheritdoc}