Google+ APIを使ってOAuth2認証しprofileデータをとってみる(3)

Controllerですべてできたー説明はコメントに記載する。

public class GoauthController extends Controller{
    private final static Logger LOG = Logger.getLogger(GoauthController.class.getName());
    private final static String CLIENT_ID = "*********************************************";
    private final static String CLIENT_SECRET = "***************";
    private final static String REDIRECT_URL = "http://***************/Goauth/callback";
    private final static String GOOGLE_API_KEY = "***************";
    private final static String OAUTH_SCOPES = "https://www.googleapis.com/auth/plus.me";
    
	/** Getですべてをまかなう */
    public Navigation doGet(){
        
        response.setContentType("application/json"); 
		
        String error = param("error");
		/** Callbackのパラメータにerrorが含まれていればParmission Errorにする */
        if (error != null) {
            response.setContentType("text/plain");
            try {
                response.getWriter().println("There was a problem during authentication: " + error);
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            LOG.severe("There was a problem during authentication: " + error);
            return null;
        }
        
        String code = param("code");
        /** Callbackのパラメータにcodeが含まれていればOAuth2認証成功 */
        if (code == null || code.isEmpty()) {
		/** 認証スタートするところ(パラメータにcodeが含まれていない) */
            // Now that we have the OAuth 2.0 code, we must exchange it for a token to make API requests.
            // Build the authorization URL
            AuthorizationRequestUrl authorizeUrl = new GoogleAuthorizationRequestUrl(CLIENT_ID, REDIRECT_URL, OAUTH_SCOPES);
			
            authorizeUrl.redirectUri = REDIRECT_URL;
            authorizeUrl.scope = OAUTH_SCOPES;
            String authorizationUrl = authorizeUrl.build();

            LOG.info("Redirecting browser for OAuth 2.0 authorization to " + authorizationUrl);
            try {
			　　 /** 認証スタート */
                response.sendRedirect(authorizationUrl);
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            return null;
         }else{
		 /** Callbackがくるところ */
             LOG.info("Exchanging OAuth code for access token using server side call");
             
			 LOG.info("callback start");
			 /** AccessTokenRequestを取得 */
             AccessTokenResponse accessTokenResponse = null;
             try {
                 accessTokenResponse = new GoogleAccessTokenRequest.GoogleAuthorizationCodeGrant(
                     new NetHttpTransport(),
                     new GsonFactory(),
                     CLIENT_ID,
                     CLIENT_SECRET,
                     code,
                     REDIRECT_URL
                     ).execute();
             } catch (IOException e) {
                 //  TODO Auto-generated catch block
                 e.printStackTrace();
             }

             /** AccessTokenがとれたーー */
             LOG.info("Storing authentication token into the session");
             LOG.info("accessToken: " + accessTokenResponse.accessToken);
             LOG.info("refreshToken: " + accessTokenResponse.refreshToken);
                 
             Plus unauthenticatedPlus = new Plus(Util.TRANSPORT, Util.JSON_FACTORY);
             unauthenticatedPlus.setKey(GOOGLE_API_KEY);
             GoogleAccessProtectedResource requestInitializer =
                     new GoogleAccessProtectedResource(
                         accessTokenResponse.accessToken,
                         Util.TRANSPORT,
                         Util.JSON_FACTORY,
                         CLIENT_ID,
                         CLIENT_SECRET,
                         accessTokenResponse.refreshToken
                         );
                     Plus plus = new Plus(Util.TRANSPORT, requestInitializer, Util.JSON_FACTORY);
              Person profile = null;
                 
              try {
                 profile = plus.people.get("me").execute();
              } catch (IOException e) {
                 // TODO Auto-generated catch block
                 e.printStackTrace();
              }
                 
             return redirect("/");
         }
     }
     return null;
 }