package com.test; import java.io.IOException; import java.net.MalformedURLException; import java.net.URL; import java.util.*; import java.util.List; import java.util.TimeZone; import java.util.logging.Logger; import javax.servlet.http.*; import com.google.api.client.http.HttpTransport; import com.google.appengine.api.appidentity.AppIdentityService; import com.google.appengine.api.appidentity.AppIdentityServiceFactory; import com.google.api.client.extensions.appengine.http.UrlFetchTransport; import com.google.api.client.googleapis.auth.oauth2.GoogleCredential; import com.google.api.client.json.jackson2.JacksonFactory; import com.google.api.services.oauth2.*; import com.google.api.services.oauth2.model.Userinfoplus; import com.google.cloud.storage.Bucket; import com.google.cloud.storage.Storage; import com.google.cloud.storage.StorageOptions; import java.util.Collection; public class TestServlet extends HttpServlet { private static final Logger log = Logger.getLogger(TestServlet.class.getName()); public void doGet(HttpServletRequest req, HttpServletResponse resp) throws IOException { resp.setContentType("text/plain"); resp.getWriter().println("Hello, world"); HttpTransport httpTransport = new UrlFetchTransport(); JacksonFactory jsonFactory = new JacksonFactory(); AppIdentityService appIdentity = AppIdentityServiceFactory.getAppIdentityService(); AppIdentityService.GetAccessTokenResult accessToken = appIdentity.getAccessToken(Arrays.asList(Oauth2Scopes.USERINFO_EMAIL)); GoogleCredential credential = new GoogleCredential.Builder() .setTransport(httpTransport) .setJsonFactory(jsonFactory).build(); credential.setAccessToken(accessToken.getAccessToken()); Oauth2 service = new Oauth2.Builder(httpTransport, jsonFactory, credential) .setApplicationName("oauth client").build(); Userinfoplus ui = service.userinfo().get().execute(); resp.getWriter().println(ui.getEmail()); // Using Google Cloud APIs Storage storage_service = StorageOptions.newBuilder() .build() .getService(); for (Bucket b : storage_service.list().iterateAll()){ System.out.println(b); } } }