google-api-client overview (2.9.0)

Google APIs.

Google APIs support based on the Apache HTTP Client.

Google APIs support based on the Apache HTTP Client v5.

Google's additions to OAuth 2.0 authorization as specified in Using OAuth 2.0 to Access Google APIs.

Before using this library, you must register your application at the APIs Console. The result of this registration process is a set of values that are known to both Google and your application, such as the "Client ID", "Client Secret", and "Redirect URIs".

These are the typical steps of the web server flow based on an authorization code, as specified in Using OAuth 2.0 for Web Server Applications:

• Redirect the end user in the browser to the authorization page using com.google.api.client.googleapis.auth.oauth2.GoogleAuthorizationCodeRequestUrl to grant your application access to the end user's protected data.
• Process the authorization response using com.google.api.client.auth.oauth2.AuthorizationCodeResponseUrl to parse the authorization code.
• Request an access token and possibly a refresh token using com.google.api.client.googleapis.auth.oauth2.GoogleAuthorizationCodeTokenRequest.
• Access protected resources using com.google.api.client.googleapis.auth.oauth2.GoogleCredential. Expired access tokens will automatically be refreshed using the refresh token (if applicable).

These are the typical steps of the browser-based client flow specified in Using OAuth 2.0 for Client-side Applications:

• Redirect the end user in the browser to the authorization page using com.google.api.client.googleapis.auth.oauth2.GoogleBrowserClientRequestUrl to grant your browser application access to the end user's protected data.
• Use the Google API Client library for JavaScript to process the access token found in the URL fragment at the redirect URI registered at the APIs Console.

Batch for Google API's.

JSON batch for Google API's.

com.google.api.client.util.Beta
Support for Google Compute Engine.

com.google.api.client.util.Beta
Utilities for Account Manager for Google accounts on Android Eclair (SDK 2.1) and later.

com.google.api.client.util.Beta
Utilities based on Google Play services.

Google App Engine utilities for OAuth 2.0 for Google APIs.

com.google.api.client.util.Beta
Support for subscribing to topics and receiving notifications on servlet-based platforms.

com.google.api.client.util.Beta
Test utilities for the com.google.api.client.googleapis.extensions.appengine.auth.oauth2 package.

com.google.api.client.util.Beta
Support for subscribing to topics and receiving notifications on servlet-based platforms.

com.google.api.client.util.Beta
Support for subscribing to topics and receiving notifications on servlet-based platforms using jakarta.servlet namespace.

Google API's support based on the java.net package.

Google's JSON support (see detailed package specification).

Package Specification

User-defined Partial JSON data models allow you to defined Plain Old Java Objects (POJO's) to define how the library should parse/serialize JSON. Each field that should be included must have an @com.google.api.client.util.Key annotation. The field can be of any visibility (private, package private, protected, or public) and must not be static. By default, the field name is used as the JSON key. To override this behavior, simply specify the JSON key use the optional value parameter of the annotation, for example @Key("name"). Any unrecognized keys from the JSON are normally simply ignored and not stored. If the ability to store unknown keys is important, use com.google.api.client.json.GenericJson.

Let's take a look at a typical partial JSON-C video feed from the YouTube Data API (as specified in YouTube Developer's Guide: JSON-C / JavaScript)

 "data":{
  "updated":"2010-01-07T19:58:42.949Z",
                  "totalItems":800,
                  "startIndex":1,
                  "itemsPerPage":1,
                  "items":[
                          {"id":"hYB0mn5zh2c",
                                  "updated":"2010-01-07T13:26:50.000Z",
                                  "title":"Google Developers Day US - Maps API Introduction",
                                  "description":"Google Maps API Introduction ...",
                                  "tags":[
                                          "GDD07","GDD07US","Maps"],
                              "player":{
                              "default":"http://www.youtube.com/watch?v=hYB0mn5zh2c" },
                              ...
                          }]}
 

Here's one possible way to design the Java data classes for this (each class in its own Java file):

 import com.google.api.client.util.*;
 import java.util.List;

 public class VideoFeed {
   @Key public int itemsPerPage;
   @Key public int startIndex;
   @Key public int totalItems;
   @Key public DateTime updated;
   @Key public List<Video> items;
 }

 public class Video {
   @Key public