code: @Override
    public <T> T doAs(final PrivilegedExceptionAction<T> action) throws Exception {
      return action.run();
    }
docs: Execute the privileged action as a given user.
  This implementation always executes the action outside the user context, simply by calling action.run().
  @param action an action to run.
  @param <T> action return type.
  @return result of an action.
  @throws Exception whatever the action can throw.