src/java.base/share/classes/jdk/internal/ref/Cleaner.java

*** 56,66 ****
   * @author Mark Reinhold
   */
  
  public class Cleaner
      extends PhantomReference<Object>
-     implements Runnable
  {
  
      // Dummy reference queue, needed because the PhantomReference constructor
      // insists that we pass a queue.  Nothing will ever be placed on this queue
      // since the reference handler invokes cleaners explicitly.
--- 56,65 ----
*** 152,164 ****
                          return null;
                      }});
          }
      }
  
-     @Override public void run() {
-         SecurityManager security = System.getSecurityManager();
-         if (security != null)
-             security.checkPackageAccess("jdk.internal.ref");
-         this.clean();
-     }
- 
  }
--- 151,156 ----