src/java.base/share/classes/java/lang/ref/Cleaner.java

*** 219,228 ****
--- 219,238 ----
          Objects.requireNonNull(action, "action");
          return new CleanerImpl.PhantomCleanableRef(obj, this, action);
      }
  
      /**
+      * Processes next Cleanable that has been waiting in the queue.
+      *
+      * @return {@code true} if a Cleanable was found in the queue and
+      * was processed or {@code false} if the queue was empty.
+      */
+     boolean cleanNextEnqueued() {
+         return impl.cleanNextEnqueued();
+     }
+ 
+     /**
       * {@code Cleanable} represents an object and a
       * cleaning action registered in a {@code Cleaner}.
       * @since 9
       */
      public interface Cleanable {