assertEquals(42, (int) future.get());
  }

  public void testSetException() throws Exception {
    SettableFuture<Object> future = SettableFuture.create();
    Exception e = new Exception("foobarbaz");
    assertTrue(future.setException(e));
    // Later attempts to set the future should return false.
    assertFalse(future.set(23));
    assertFalse(future.setException(new Exception("quux")));