| FileSystem | core/lib/Drupal/Core/File/FileSystem.php | Provides helpers to operate on files and stream wrappers. | 
          
                  | FileSystemInterface | core/lib/Drupal/Core/File/FileSystemInterface.php | Provides an interface for helpers that operate on files and stream wrappers. | 
          
                  | FileUrlGenerator | core/lib/Drupal/Core/File/FileUrlGenerator.php | Default implementation for the file URL generator service. | 
          
                  | FileUrlGeneratorInterface | core/lib/Drupal/Core/File/FileUrlGeneratorInterface.php | Generates file URLs for a stream to an external or local file. | 
          
                  | HtaccessWriter | core/lib/Drupal/Core/File/HtaccessWriter.php | Provides functions to manage Apache .htaccess files. | 
          
                  | HtaccessWriterInterface | core/lib/Drupal/Core/File/HtaccessWriterInterface.php | Interface for managing Apache .htaccess files. | 
          
                  | ProtectedDirectory | core/lib/Drupal/Core/File/ProtectedDirectory.php | A value object representing a protected directory. |