Google APIs Client Library for Java

Setup Instructions
Component Modules
Google App Engine
Media Download
Media Upload
OAuth 2.0
Timeouts and Errors

Running on Google App Engine

App Engine-specific helpers make quick work of authenticated calls to APIs, and you do not need to worry about exchanging code for tokens.

For example:

protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws IOException {
  AppIdentityCredential credential =
      new AppIdentityCredential(Arrays.asList(UrlshortenerScopes.URLSHORTENER));
  Urlshortener shortener =
      new Urlshortener.Builder(new UrlFetchTransport(), new JacksonFactory(), credential)
  UrlHistory history = shortener.URL().list().execute();

Auth helpers

If you are building a web app that interacts with a user’s data via an OAuth 2.0-enabled API, we’ve created some helpers to assist you with the process. The helpers aim to:

Getting started

  1. Install the Google API Client Library for Java:
    • Follow the download instructions and put the library jar files into your war/WEB-INF/lib directory.
    • Alternatively, you can use Maven.
  2. Learn about using OAuth 2.0 with the authorization code flow for Google App Engine applications.
  3. Learn about using OAuth 2.0 with the Google App Engine Identity API.
  4. Take a look at the Calendar App Engine sample. This sample combines our Java library and auth helpers to show you how to access end-user data from within a Google App Engine web app. The sample also uses GWT for the user interface.