diff --git a/core/lib/Drupal/Core/TypedData/Plugin/DataType/Language.php b/core/lib/Drupal/Core/TypedData/Plugin/DataType/Language.php
index 8be31e5..dd51f65 100644
--- a/core/lib/Drupal/Core/TypedData/Plugin/DataType/Language.php
+++ b/core/lib/Drupal/Core/TypedData/Plugin/DataType/Language.php
@@ -78,7 +78,7 @@ class Language extends TypedData {
    */
   public function getString() {
     $language = $this->getValue();
-    return $language ? $language->name : '';
+    return $language ? $language->getName() : '';
   }
 
   /**
@@ -89,7 +89,7 @@ class Language extends TypedData {
       return $this->id;
     }
     elseif (isset($this->language)) {
-      return $this->language->id;
+      return $this->language->getId();
     }
   }
 
diff --git a/core/lib/Drupal/Core/TypedData/Plugin/DataType/LanguageReference.php b/core/lib/Drupal/Core/TypedData/Plugin/DataType/LanguageReference.php
index 9fbaa21..5f2669d 100644
--- a/core/lib/Drupal/Core/TypedData/Plugin/DataType/LanguageReference.php
+++ b/core/lib/Drupal/Core/TypedData/Plugin/DataType/LanguageReference.php
@@ -32,7 +32,7 @@ class LanguageReference extends DataReferenceBase {
    */
   public function getTargetIdentifier() {
     $language = $this->getTarget();
-    return isset($language) ? $language->id() : NULL;
+    return isset($language) ? $language->getId() : NULL;
   }
 
 }
diff --git a/core/modules/block/block.module b/core/modules/block/block.module
index 88b6ecc..23e6593 100644
--- a/core/modules/block/block.module
+++ b/core/modules/block/block.module
@@ -438,8 +438,8 @@ function block_language_entity_delete(Language $language) {
   // Remove the block visibility settings for the deleted language.
   foreach (entity_load_multiple('block') as $block) {
     $visibility = $block->get('visibility');
-    if (isset($visibility['language']['langcodes'][$language->id()])) {
-      unset($visibility['language']['langcodes'][$language->id()]);
+    if (isset($visibility['language']['langcodes'][$language->gtetId()])) {
+      unset($visibility['language']['langcodes'][$language->getId()]);
       $block->set('visibility', $visibility);
       $block->save();
     }
diff --git a/core/modules/language/language.module b/core/modules/language/language.module
index efbf47d..beed875 100644
--- a/core/modules/language/language.module
+++ b/core/modules/language/language.module
@@ -82,7 +82,7 @@ function language_help($route_name, Request $request) {
  *   Use \Drupal\language\LanguageAccessController.
  */
 function language_access_language_edit_or_delete($language) {
-  return !$language->locked && \Drupal::currentUser()->hasPermission('administer languages');
+  return !$language->isLocked() && \Drupal::currentUser()->hasPermission('administer languages');
 }
 
 /**
@@ -592,13 +592,13 @@ function language_modules_uninstalled($modules) {
  * Implements hook_ENTITY_TYPE_insert() for 'language_entity'.
  */
 function language_language_entity_insert(LanguageEntity $language) {
-  if (!empty($language->locked)) {
+  if (!empty($language->isLocked())) {
     return;
   }
 
   // Add language to the list of language domains.
   $domains = language_negotiation_url_domains();
-  $domains[$language->id()] = '';
+  $domains[$language->getId()] = '';
   language_negotiation_url_domains_save($domains);
 }
 
@@ -608,12 +608,12 @@ function language_language_entity_insert(LanguageEntity $language) {
 function language_language_entity_delete(LanguageEntity $language) {
   // Remove language from language prefix list.
   $prefixes = language_negotiation_url_prefixes();
-  unset($prefixes[$language->id()]);
+  unset($prefixes[$language->getId()]);
   language_negotiation_url_prefixes_save($prefixes);
 
   // Remove language from language domain list.
   $domains = language_negotiation_url_domains();
-  unset($domains[$language->id()]);
+  unset($domains[$language->getId()]);
   language_negotiation_url_domains_save($domains);
 }
 
diff --git a/core/modules/language/lib/Drupal/language/Form/LanguageFormBase.php b/core/modules/language/lib/Drupal/language/Form/LanguageFormBase.php
index 583787a..2e4c573 100644
--- a/core/modules/language/lib/Drupal/language/Form/LanguageFormBase.php
+++ b/core/modules/language/lib/Drupal/language/Form/LanguageFormBase.php
@@ -9,9 +9,9 @@
 
 use Drupal\Component\Utility\String;
 use Drupal\Core\Entity\EntityForm;
-use Drupal\Core\Language\LanguageInterface;
 use Drupal\language\ConfigurableLanguageManagerInterface;
 use Symfony\Component\DependencyInjection\ContainerInterface;
+use Drupal\Core\Language\LanguageInterface;
 
 /**
  * Base form for language add and edit forms.
@@ -49,15 +49,15 @@
    */
   public function commonForm(array &$form) {
     $language = $this->entity;
-    if (isset($language->id)) {
+    if (isset($language->getId())) {
       $form['langcode_view'] = array(
         '#type' => 'item',
         '#title' => $this->t('Language code'),
-        '#markup' => $language->id
+        '#markup' => $language->getId()
       );
       $form['langcode'] = array(
         '#type' => 'value',
-        '#value' => $language->id
+        '#value' => $language->getId()
       );
     }
     else {
@@ -75,7 +75,7 @@
       '#type' => 'textfield',
       '#title' => $this->t('Language name in English'),
       '#maxlength' => 64,
-      '#default_value' => $language->label,
+      '#default_value' => $language->label(),
       '#required' => TRUE,
     );
     $form['direction'] = array(
@@ -83,7 +83,7 @@
       '#title' => $this->t('Direction'),
       '#required' => TRUE,
       '#description' => $this->t('Direction that text in this language is presented.'),
-      '#default_value' => $language->direction,
+      '#default_value' => $language->getDirection(),
       '#options' => array(
         LanguageInterface::DIRECTION_LTR => $this->t('Left to right'),
         LanguageInterface::DIRECTION_RTL => $this->t('Right to left'),
diff --git a/core/modules/language/lib/Drupal/language/Plugin/Condition/Language.php b/core/modules/language/lib/Drupal/language/Plugin/Condition/Language.php
index cc20f42..e3f0563 100644
--- a/core/modules/language/lib/Drupal/language/Plugin/Condition/Language.php
+++ b/core/modules/language/lib/Drupal/language/Plugin/Condition/Language.php
@@ -35,7 +35,7 @@ class Language extends ConditionPluginBase {
       $languages = language_list(Lang::STATE_ALL);
       $langcodes_options = array();
       foreach ($languages as $language) {
-        $langcodes_options[$language->id] = $language->label();
+        $langcodes_options[$language->getId()] = $language->label();
       }
       $form['langcodes'] = array(
         '#type' => 'checkboxes',
diff --git a/core/modules/language/lib/Drupal/language/Tests/LanguageConfigurationTest.php b/core/modules/language/lib/Drupal/language/Tests/LanguageConfigurationTest.php
index 03edfaf..e9dff48 100644
--- a/core/modules/language/lib/Drupal/language/Tests/LanguageConfigurationTest.php
+++ b/core/modules/language/lib/Drupal/language/Tests/LanguageConfigurationTest.php
@@ -177,8 +177,8 @@ function testLanguageConfigurationWeight() {
 
     $languages = entity_load_multiple('language_entity', NULL, TRUE);
     foreach ($languages as $language) {
-      if (!$language->locked && $language->weight > $max_weight) {
-        $max_weight = $language->weight;
+      if (!$language->isLocked() && $language->getWeight() > $max_weight) {
+        $max_weight = $language->getWeight();
       }
     }
 
diff --git a/core/modules/locale/locale.module b/core/modules/locale/locale.module
index 97bb3a9..3aa830c 100644
--- a/core/modules/locale/locale.module
+++ b/core/modules/locale/locale.module
@@ -227,7 +227,7 @@ function locale_language_entity_insert(LanguageEntity $language) {
   // Changing the language settings impacts the interface: clear render cache.
   \Drupal::cache('render')->deleteAll();
   // Force JavaScript translation file re-creation for the new language.
-  _locale_invalidate_js($language->id());
+  _locale_invalidate_js($language->getId());
 }
 
 /**
@@ -238,7 +238,7 @@ function locale_language_entity_update(LanguageEntity $language) {
   // Changing the language settings impacts the interface: clear render cache.
   \Drupal::cache('render')->deleteAll();
   // Force JavaScript translation file re-creation for the modified language.
-  _locale_invalidate_js($language->id());
+  _locale_invalidate_js($language->getId());
 }
 
 /**
@@ -246,22 +246,22 @@ function locale_language_entity_update(LanguageEntity $language) {
  */
 function locale_language_entity_delete(LanguageEntity $language) {
   // Remove translations.
-  \Drupal::service('locale.storage')->deleteTranslations(array('language' => $language->id()));
+  \Drupal::service('locale.storage')->deleteTranslations(array('language' => $language->getId()));
 
   // Remove interface translation files.
   module_load_include('inc', 'locale', 'locale.bulk');
-  locale_translate_delete_translation_files(array(), array($language->id()));
+  locale_translate_delete_translation_files(array(), array($language->getId()));
 
   // Remove translated configuration objects.
-  \Drupal\locale\Locale::config()->deleteLanguageTranslations($language->id());
+  \Drupal\locale\Locale::config()->deleteLanguageTranslations($language->getId());
 
   // Changing the language settings impacts the interface:
-  _locale_invalidate_js($language->id());
+  _locale_invalidate_js($language->getId());
   \Drupal::cache('render')->deleteAll();
 
   // Clear locale translation caches.
-  locale_translation_status_delete_languages(array($language->id()));
-  \Drupal::cache()->delete('locale:' . $language->id());
+  locale_translation_status_delete_languages(array($language->getId()));
+  \Drupal::cache()->delete('locale:' . $language->getId());
 }
 
 /**
@@ -665,7 +665,7 @@ function locale_form_language_admin_overview_form_alter(&$form, &$form_state) {
       'translated' => 0,
       'ratio' => 0,
     );
-    if (!$language->locked && ($langcode != 'en' || locale_translate_english())) {
+    if (!$language->isLocked() && ($langcode != 'en' || locale_translate_english())) {
       $form['languages'][$langcode]['locale_statistics'] = array(
         '#markup' => l(
           t('@translated/@total (@ratio%)', array(
diff --git a/core/modules/node/lib/Drupal/node/NodeStorage.php b/core/modules/node/lib/Drupal/node/NodeStorage.php
index 8bb17fd..89162f6 100644
--- a/core/modules/node/lib/Drupal/node/NodeStorage.php
+++ b/core/modules/node/lib/Drupal/node/NodeStorage.php
@@ -10,7 +10,7 @@
 use Drupal\Core\Database\Database;
 use Drupal\Core\Entity\ContentEntityDatabaseStorage;
 use Drupal\Core\Session\AccountInterface;
-use Drupal\Core\Language\Language;
+use Drupal\Core\Language\LanguageInterface;
 
 /**
  * Defines the controller class for nodes.
@@ -55,8 +55,8 @@ class NodeStorage extends ContentEntityDatabaseStorage implements NodeStorageInt
    */
   public function clearRevisionsLanguage($language) {
     return $this->database->update('node_revision')
-      ->fields(array('langcode' => Language::LANGCODE_NOT_SPECIFIED))
-      ->condition('langcode', $language->id)
+      ->fields(array('langcode' => LanguageInterface::LANGCODE_NOT_SPECIFIED))
+      ->condition('langcode', $language->getId())
       ->execute();
   }
 }
diff --git a/core/modules/node/lib/Drupal/node/Plugin/views/field/Language.php b/core/modules/node/lib/Drupal/node/Plugin/views/field/Language.php
index af705cb..9d12a1d 100644
--- a/core/modules/node/lib/Drupal/node/Plugin/views/field/Language.php
+++ b/core/modules/node/lib/Drupal/node/Plugin/views/field/Language.php
@@ -44,7 +44,7 @@ class Language extends Node {
     // ready, see http://drupal.org/node/1616594.
     $value = $this->getValue($values);
     $language = language_load($value);
-    $value = $language ? $language->name : '';
+    $value = $language ? $language->getName() : '';
     return $this->renderLink($value, $values);
   }
 
diff --git a/core/modules/node/lib/Drupal/node/Tests/NodeAccessLanguageTest.php b/core/modules/node/lib/Drupal/node/Tests/NodeAccessLanguageTest.php
index e90b48b..3357792 100644
--- a/core/modules/node/lib/Drupal/node/Tests/NodeAccessLanguageTest.php
+++ b/core/modules/node/lib/Drupal/node/Tests/NodeAccessLanguageTest.php
@@ -260,7 +260,7 @@ function testNodeAccessQueryTag() {
     // langcode is given it will use the fallback node.
     $this->assertEqual(count($nids), 2, 'db_select() returns 2 node');
     $this->assertTrue(array_key_exists($node_public->id(), $nids), 'Returned node ID is public node.');
-    $this->assertTrue(array_key_exists($node_no_language->id(), $nids), 'Returned node ID is no language node.');
+    $this->assertTrue(array_key_exists($node_no_language->getId(), $nids), 'Returned node ID is no language node.');
 
     // Query the nodes table as the web user with the node access tag and
     // langcode de.