diff --git a/core/modules/rest/src/LinkManager/CollectionLinkManager.php b/core/modules/rest/src/LinkManager/CollectionLinkManager.php
index 79c8747..2b3ff99 100644
--- a/core/modules/rest/src/LinkManager/CollectionLinkManager.php
+++ b/core/modules/rest/src/LinkManager/CollectionLinkManager.php
@@ -16,7 +16,8 @@ class CollectionLinkManager implements CollectionLinkManagerInterface {
    */
   public function getCollectionItemRelation($collection_id) {
     // By default, use the item IANA Link Relation, which is a generic way to
-    // link to items from a collection. See http://tools.ietf.org/html/rfc6573.
+    // link to items from a collection.
+    // @see http://tools.ietf.org/html/rfc6573.
     return 'item';
   }
 
diff --git a/core/modules/rest/src/LinkManager/CollectionLinkManagerInterface.php b/core/modules/rest/src/LinkManager/CollectionLinkManagerInterface.php
index 2713f6b..1e4be98 100644
--- a/core/modules/rest/src/LinkManager/CollectionLinkManagerInterface.php
+++ b/core/modules/rest/src/LinkManager/CollectionLinkManagerInterface.php
@@ -13,7 +13,7 @@
 interface CollectionLinkManagerInterface {
 
   /**
-   * Get link relating collection to item.
+   * Get link relations to items in a collection.
    *
    * @param string $collection_id
    *   The identifier of a collection (e.g. View name).
diff --git a/core/modules/rest/src/Plugin/views/style/Serializer.php b/core/modules/rest/src/Plugin/views/style/Serializer.php
index c3f823f..68ba03a 100644
--- a/core/modules/rest/src/Plugin/views/style/Serializer.php
+++ b/core/modules/rest/src/Plugin/views/style/Serializer.php
@@ -53,7 +53,7 @@ class Serializer extends StylePluginBase {
    *
    * @var array
    */
-  protected $formats = array();
+  protected $formats = [];
 
   /**
    * The URL generator service.
@@ -186,14 +186,14 @@ public function getCollection() {
 
     // Inject the page into the canonical URI of the view.
     if ($this->view->getCurrentPage() > 0) {
-      $uri = $this->urlGenerator->generateFromRoute($route_name, array(), array('query' => array('page' => $this->view->getCurrentPage()), 'absolute' => TRUE));
+      $uri = $this->urlGenerator->generateFromRoute($route_name, [], array('query' => array('page' => $this->view->getCurrentPage()), 'absolute' => TRUE));
     }
     else {
-      $uri = $this->urlGenerator->generateFromRoute($route_name, array(), array('absolute' => TRUE));
+      $uri = $this->urlGenerator->generateFromRoute($route_name, [], array('absolute' => TRUE));
     }
     $collection->setUri($uri);
 
-    $rows = array();
+    $rows = [];
     foreach ($this->view->result as $row) {
       $rows[] = $this->view->rowPlugin->render($row);
     }
@@ -209,14 +209,14 @@ public function getCollection() {
       // Starting at page=0 we need to decrement.
       $total = ceil($pager->getTotalItems() / $pager->getItemsPerPage()) - 1;
 
-      $collection->setLink('first', $this->urlGenerator->generateFromRoute($route_name, array(), array(
+      $collection->setLink('first', $this->urlGenerator->generateFromRoute($route_name, [], array(
         'query' => array('page' => 0),
         'absolute' => TRUE,
       )));
 
       // If we are not on the first page add a previous link.
       if ($current_page > 0) {
-        $collection->setLink('prev', $this->urlGenerator->generateFromRoute($route_name, array(), array(
+        $collection->setLink('prev', $this->urlGenerator->generateFromRoute($route_name, [], array(
           'query' => array('page' => $current_page - 1),
           'absolute' => TRUE,
         )));
@@ -224,13 +224,13 @@ public function getCollection() {
 
       // If we are not on the last page add a next link.
       if ($current_page < $total) {
-        $collection->setLink('next', $this->urlGenerator->generateFromRoute($route_name, array(), array(
+        $collection->setLink('next', $this->urlGenerator->generateFromRoute($route_name, [], array(
           'query' => array('page' => $current_page + 1),
           'absolute' => TRUE,
         )));
       }
 
-      $collection->setLink('last', $this->urlGenerator->generateFromRoute($route_name, array(), array(
+      $collection->setLink('last', $this->urlGenerator->generateFromRoute($route_name, [], array(
         'query' => array('page' => $total),
         'absolute' => TRUE,
       )));
diff --git a/core/modules/serialization/src/Collection.php b/core/modules/serialization/src/Collection.php
index 451af3d..e3fd9aa 100644
--- a/core/modules/serialization/src/Collection.php
+++ b/core/modules/serialization/src/Collection.php
@@ -23,7 +23,7 @@ class Collection implements \IteratorAggregate {
    *
    * @var array
    */
-  protected $items;
+  protected $items = [];
 
   /**
    * The title of the collection.
@@ -51,7 +51,7 @@ class Collection implements \IteratorAggregate {
    *
    * @var array
    */
-  protected $links = array();
+  protected $links = [];
 
   /**
    * Constructor.