Urlshortener.Builder builder = new Urlshortener.Builder(TRANSPORT, JSON_FACTORY, credential);
builder.setApplicationName(Constants.GOOGLE_APPLICATION_NAME);
Urlshortener urlshortener = builder.build();
// URLの設定
Url url = new Url();
url.setLongUrl("http://plucial.com/u/" + userModel.getKey().getName() + "/a/" +activityModel.getKey().getName());
// 短縮URLの発行
url = urlshortener.url().insert(url).execute();
return url.getId();
}