code: public void popCallbackBeanO() // d662032
      {
          final boolean isTraceOn = TraceComponent.isAnyTracingEnabled();
          if (isTraceOn && tc.isDebugEnabled())
              Tr.debug(tc, "popCallbackBeanO: " + ivCallbackBeanOStack.peek());
  
          ivHandleListContext.endContext();
          BeanO beanO = ivCallbackBeanOStack.pop();
          beanO.parkHandleList();
      }
docs: Restores the callback bean after removing the thread context established
  by a previous call to {@link #pushCallbackBeanO}.