seal Platform.Preferences

Author: mstr2

modules/javafx.graphics/src/main/java/com/sun/javafx/application/preferences/PlatformPreferences.java

@@ -51,7 +51,7 @@
  * When the operating system signals that a preference has changed, the mappings are updated
  * by calling the {@link #update(Map)} method.
  */
-public class PlatformPreferences extends AbstractMap<String, Object> implements Platform.Preferences {
+public final class PlatformPreferences extends AbstractMap<String, Object> implements Platform.Preferences {
 
     /**
      * Contains mappings from platform-specific keys to their types. This information is

modules/javafx.graphics/src/main/java/javafx/application/Platform.java

@@ -583,7 +583,8 @@ public static Preferences getPreferences() {
      *
      * @since 22
      */
-    public interface Preferences extends ObservableMap<String, Object> {
+    public sealed interface Preferences extends ObservableMap<String, Object>
+            permits com.sun.javafx.application.preferences.PlatformPreferences {
 
         /**
          * Specifies whether applications should minimize the amount of non-essential animations,