Java tutorial
/* * Copyright (c) 2013 Google Inc. * * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except * in compliance with the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software distributed under the License * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express * or implied. See the License for the specific language governing permissions and limitations under * the License. */ package com.utilties.util.gmail; import com.google.api.client.extensions.appengine.datastore.AppEngineDataStoreFactory; import com.google.api.client.extensions.appengine.http.UrlFetchTransport; import com.google.api.client.googleapis.auth.oauth2.GoogleAuthorizationCodeFlow; import com.google.api.client.googleapis.auth.oauth2.GoogleClientSecrets; import com.google.api.client.http.GenericUrl; import com.google.api.client.json.jackson2.JacksonFactory; import com.google.api.client.util.Preconditions; import com.google.api.client.util.store.DataStoreFactory; import com.google.api.services.gmail.GmailScopes; import java.io.IOException; import java.io.InputStreamReader; import java.util.Collections; import java.util.Set; import javax.servlet.http.HttpServletRequest; public class Utils { /** * Global instance of the {@link DataStoreFactory}. The best practice is to make it a single * globally shared instance across your application. */ private static final AppEngineDataStoreFactory DATA_STORE_FACTORY = AppEngineDataStoreFactory .getDefaultInstance(); private static GoogleClientSecrets clientSecrets = null; private static final Set<String> SCOPES = Collections.singleton(GmailScopes.GMAIL_SEND); public static final String MAIN_SERVLET_PATH = "/plussampleservlet"; public static final String AUTH_CALLBACK_SERVLET_PATH = "/oauth2callback"; public static final UrlFetchTransport HTTP_TRANSPORT = new UrlFetchTransport(); public static final JacksonFactory JSON_FACTORY = JacksonFactory.getDefaultInstance(); private static GoogleClientSecrets getClientSecrets() throws IOException { if (clientSecrets == null) { clientSecrets = GoogleClientSecrets.load(JSON_FACTORY, new InputStreamReader(Utils.class.getResourceAsStream("/client_secret.json"))); /* Preconditions.checkArgument(!clientSecrets.getDetails().getClientId().startsWith("Enter ") && !clientSecrets.getDetails().getClientSecret().startsWith("Enter "), "Download client_secrets.json file from https://code.google.com/apis/console/?api=plus " + "into plus-appengine-sample/src/main/resources/client_secrets.json");*/ } return clientSecrets; } public static GoogleAuthorizationCodeFlow initializeFlow() throws IOException { return new GoogleAuthorizationCodeFlow.Builder(HTTP_TRANSPORT, JSON_FACTORY, getClientSecrets(), SCOPES) .setDataStoreFactory(DATA_STORE_FACTORY).setAccessType("offline").build(); } public static String getRedirectUri(HttpServletRequest req) { GenericUrl requestUrl = new GenericUrl(req.getRequestURL().toString()); requestUrl.setRawPath(AUTH_CALLBACK_SERVLET_PATH); return requestUrl.build(); } }