@Test
public void testInvalidatingOneAccessTokenDoesNotAffectOther() {

    ByteBuffer username = getAcceptableUsername();
    ByteBuffer password = getSecurePassword();
    service.create(username, password, Role.ADMIN);
    AccessToken token1 = service.tokens.issue(username);
    AccessToken token2 = service.tokens.issue(username);
    service.tokens.expire(token2);
    Assert.assertTrue(service.tokens.isValid(token1));
}