} finally {
      joinPool(e);
    }
  }

  /** invokeAny(c) returns result of some task in c if at least one completes */
  public void testInvokeAnyImpl() throws Exception {
    ListeningExecutorService e = newDirectExecutorService();
    try {
      List<Callable<String>> l = new ArrayList<>();
      l.add(new StringTask());
      l.add(new StringTask());