Java tutorial
/* * Copyright 2014 Artem Chikin * Copyright 2014 Artem Herasymchuk * Copyright 2014 Tom Krywitsky * Copyright 2014 Henry Pabst * Copyright 2014 Bradley Simons * * 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 ca.ualberta.cmput301w14t08.geochan.helpers; import android.graphics.Bitmap; import android.location.Location; import ca.ualberta.cmput301w14t08.geochan.json.BitmapJsonConverter; import ca.ualberta.cmput301w14t08.geochan.json.CommentJsonConverter; import ca.ualberta.cmput301w14t08.geochan.json.CommentOfflineJsonConverter; import ca.ualberta.cmput301w14t08.geochan.json.LocationJsonConverter; import ca.ualberta.cmput301w14t08.geochan.json.ThreadCommentJsonConverter; import ca.ualberta.cmput301w14t08.geochan.json.ThreadCommentOfflineJsonConverter; import ca.ualberta.cmput301w14t08.geochan.models.Comment; import ca.ualberta.cmput301w14t08.geochan.models.ThreadComment; import com.google.gson.Gson; import com.google.gson.GsonBuilder; /** * Genereates and returns Gson objects with the required type converters set. * * @author Artem Herasymchuk */ public class GsonHelper { private static Gson offlineGson = null; private static Gson onlineGson = null; private static Gson exposeGson = null; private static GsonHelper instance = null; private GsonHelper() { GsonBuilder builder = new GsonBuilder(); builder.registerTypeAdapter(Comment.class, new CommentJsonConverter()); builder.registerTypeAdapter(ThreadComment.class, new ThreadCommentJsonConverter()); builder.registerTypeAdapter(Bitmap.class, new BitmapJsonConverter()); builder.registerTypeAdapter(Location.class, new LocationJsonConverter()); onlineGson = builder.create(); builder = new GsonBuilder(); builder.registerTypeAdapter(Comment.class, new CommentOfflineJsonConverter()); builder.registerTypeAdapter(ThreadComment.class, new ThreadCommentOfflineJsonConverter()); builder.registerTypeAdapter(Location.class, new LocationJsonConverter()); offlineGson = builder.create(); builder = new GsonBuilder(); exposeGson = builder.excludeFieldsWithoutExposeAnnotation().create(); } public static GsonHelper getInstance() { if (instance == null) { instance = new GsonHelper(); } return instance; } public static Gson getOnlineGson() { if (onlineGson == null) { getInstance(); } return onlineGson; } public static Gson getOfflineGson() { if (offlineGson == null) { getInstance(); } return offlineGson; } public static Gson getExposeGson() { if (exposeGson == null) { getInstance(); } return exposeGson; } }