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.ericrgon; import android.app.Activity; import android.app.Fragment; import android.util.Log; import com.google.api.client.extensions.android.http.AndroidHttp; import com.google.api.client.googleapis.extensions.android.gms.auth.GoogleAccountCredential; import com.google.api.client.http.ExponentialBackOffPolicy; import com.google.api.client.http.HttpRequest; import com.google.api.client.http.HttpRequestInitializer; import com.google.api.client.json.gson.GsonFactory; import com.google.cloud.backend.android.mobilebackend.Mobilebackend; import com.google.cloud.backend.android.mobilebackend.model.EntityDto; import com.google.cloud.backend.android.mobilebackend.model.EntityListDto; import com.google.cloud.backend.android.mobilebackend.model.QueryDto; import java.io.IOException; import java.util.LinkedList; import java.util.List; /** * Base Cloud Backend API class that provides CRUD operation and query operation * on the backend. All the methods work synchronously, so they can not be called * directly from UI thread of {@link Activity} or {@link Fragment}. (Use * {@link CloudBackendAsync} for calling backend from UI thread). See * {@link CloudBackendTest} for detailed usage. * */ public class CloudBackend { static { // to prevent EOFException after idle // http://code.google.com/p/google-http-java-client/issues/detail?id=116 System.setProperty("http.keepAlive", "false"); } private GoogleAccountCredential credential; /** * Sets {@link GoogleAccountCredential} that will be used on all backend * calls. By setting null, all call will not be associated with user account * info. * * @param credential * {@link GoogleAccountCredential} */ public void setCredential(GoogleAccountCredential credential) { this.credential = credential; } /** * Returns {@link GoogleAccountCredential} that has been set to this backend. * * @return {@link GoogleAccountCredential} */ public GoogleAccountCredential getCredential() { return this.credential; } // building CloudBackend endpoints and configuring authentication and // exponential back-off policy private Mobilebackend getMBSEndpoint() { // check if credential has account name final GoogleAccountCredential gac = credential == null || credential.getSelectedAccountName() == null ? null : credential; // create HttpRequestInitializer HttpRequestInitializer hri = new HttpRequestInitializer() { @Override public void initialize(HttpRequest request) throws IOException { request.setBackOffPolicy(new ExponentialBackOffPolicy()); if (gac != null) { gac.initialize(request); } } }; // build MBS builder // (specify gac or hri as the third parameter) return new Mobilebackend.Builder(AndroidHttp.newCompatibleTransport(), new GsonFactory(), hri) .setRootUrl(Consts.ENDPOINT_ROOT_URL).build(); } /** * Inserts a CloudEntity into the backend synchronously. * * @param ce * {@link CloudEntity} for inserting a CloudEntity. * @return {@link CloudEntity} that has updated fields (like updatedAt and new * Id). * @throws IOException * When the call had failed for any reason. */ public CloudEntity insert(CloudEntity ce) throws IOException { EntityDto resultEntityDto = getMBSEndpoint().insert(ce.getKindName(), ce.getEntityDto()).execute(); CloudEntity resultCo = CloudEntity.createCloudEntityFromEntityDto(resultEntityDto); Log.i(Consts.TAG, "insert: inserted: " + resultCo); return resultCo; } /** * Updates the specified {@link CloudEntity} on the backend synchronously. If * it does not have any Id, it creates a new Entity. If it has, find the * existing entity and update it. * * @param ce * {@link CloudEntity} for updating a CloudEntity. * @return {@link CloudEntity} that has updated fields (like updatedAt and new * Id). * @throws IOException * When the call had failed for any reason. */ public CloudEntity update(CloudEntity ce) throws IOException { EntityDto resultEntityDto = getMBSEndpoint().update(ce.getKindName(), ce.getEntityDto()).execute(); CloudEntity resultCo = CloudEntity.createCloudEntityFromEntityDto(resultEntityDto); Log.i(Consts.TAG, "update: updated: " + resultCo); return resultCo; } /** * Inserts multiple {@link CloudEntity}s on the backend synchronously. Works * just the same as {@link #insert(CloudEntity)}. * * @param ceList * {@link List} that holds {@link CloudEntity}s to save. * @return {@link List} that has updated {@link CloudEntity}s. * @throws IOException * When the call had failed for any reason. */ public List<CloudEntity> insertAll(List<CloudEntity> ceList) throws IOException { // prepare for EntityListDto List<EntityDto> cdList = new LinkedList<EntityDto>(); for (CloudEntity co : ceList) { cdList.add(co.getEntityDto()); } EntityListDto cdl = new EntityListDto(); cdl.setEntries(cdList); // execute saveAll EntityListDto resultCdl; resultCdl = getMBSEndpoint().insertAll(cdl).execute(); Log.i(Consts.TAG, "saveAll: saved: " + resultCdl.getEntries()); List<CloudEntity> resultCoList = getListOfEntityDto(resultCdl); return resultCoList; } /** * Updates multiple {@link CloudEntity}s on the backend synchronously. Works * just the same as {@link #update(CloudEntity)}. * * @param coList * {@link List} that holds {@link CloudEntity}s to save. * @return {@link List} that has updated {@link CloudEntity}s. * @throws IOException * When the call had failed for any reason. */ public List<CloudEntity> updateAll(List<CloudEntity> coList) throws IOException { // prepare for EntityListDto List<EntityDto> cdList = new LinkedList<EntityDto>(); for (CloudEntity co : coList) { cdList.add(co.getEntityDto()); } EntityListDto cdl = new EntityListDto(); cdl.setEntries(cdList); // execute saveAll EntityListDto resultCdl; resultCdl = getMBSEndpoint().updateAll(cdl).execute(); Log.i(Consts.TAG, "saveAll: saved: " + resultCdl.getEntries()); List<CloudEntity> resultCoList = getListOfEntityDto(resultCdl); return resultCoList; } /** * Reads the specified {@link CloudEntity} synchronously. * * @param kindName * Name of the table for the CloudEntity to get. * @param id * Id of the CloudEntity to find. * @return {@link CloudEntity}. * @throws IOException * When the call had failed for any reason. */ public CloudEntity get(String kindName, String id) throws IOException { EntityDto cd = getMBSEndpoint().get(kindName, id).execute(); CloudEntity co = CloudEntity.createCloudEntityFromEntityDto(cd); Log.i(Consts.TAG, "get: result: " + co); return co; } /** * Reads all the {@link CloudEntity}s synchronously specified by the * {@link List} of Ids. * * @param kindName * Name of the table for the CloudEntities to get. * @param idList * {@link List} of Ids of the CloudEntities to find. * @return {@link List} of the found {@link CloudEntity}s. * @throws IOException * When the call had failed for any reason. */ public List<CloudEntity> getAll(String kindName, List<String> idList) throws IOException { // prepare for EntityListDto EntityListDto cdl = createEntityListDto(kindName, idList); // execute getAll EntityListDto resultCdl; resultCdl = getMBSEndpoint().getAll(cdl).execute(); Log.i(Consts.TAG, "getAll: result: " + resultCdl.getEntries()); return getListOfEntityDto(resultCdl); } private EntityListDto createEntityListDto(String kindName, List<String> idList) { List<EntityDto> l = new LinkedList<EntityDto>(); for (String id : idList) { EntityDto cd = new EntityDto(); cd.setId(id); cd.setKindName(kindName); l.add(cd); } EntityListDto cdl = new EntityListDto(); cdl.setEntries(l); return cdl; } private List<CloudEntity> getListOfEntityDto(EntityListDto cdl) { List<CloudEntity> l = new LinkedList<CloudEntity>(); if (cdl.getEntries() != null) { // production returns null when its // empty for (EntityDto cd : cdl.getEntries()) { l.add(CloudEntity.createCloudEntityFromEntityDto(cd)); } } return l; } /** * Deletes the specified {@link CloudEntity} synchronously. * * @param kindName * Name of the table for the CloudEntity to delete. * @param id * Id of the CloudEntity to delete. * @throws IOException * When the call had failed for any reason. */ public void delete(String kindName, String id) throws IOException { getMBSEndpoint().delete(kindName, id).execute(); Log.i(Consts.TAG, "delete: deleted: " + kindName + "/" + id); } /** * Deletes the specified {@link CloudEntity} synchronously. * * @param co * {@link CloudEntity} to delete * @throws IOException * When the call had failed for any reason. */ public void delete(CloudEntity co) throws IOException { getMBSEndpoint().delete(co.getKindName(), co.getId()).execute(); Log.i(Consts.TAG, "delete: deleted: " + co); } /** * Deletes all the specified {@link CloudEntity}s synchronously. * * @param kindName * Name of the table for the CloudEntity to delete. * @param idList * {@link List} that contains a list of Ids to delete. * @throws IOException * When the call had failed for any reason. */ public void deleteAllById(String kindName, List<String> idList) throws IOException { // prepare for EntityListDto EntityListDto cdl = createEntityListDto(kindName, idList); // delete getMBSEndpoint().deleteAll(cdl).execute(); Log.i(Consts.TAG, "deleteAll: deleted: " + kindName + ": " + idList); } /** * Deletes all the specified {@link CloudEntity}s synchronously. * * @param kindName * Name of the table for the CloudEntity to delete. * @param coList * {@link List} that contains a list of Cloud to delete. * @throws IOException * When the call had failed for any reason. */ public void deleteAll(String kindName, List<CloudEntity> coList) throws IOException { List<String> idList = new LinkedList<String>(); for (CloudEntity co : coList) { idList.add(co.getId()); } deleteAllById(kindName, idList); } /** * Executes a query synchronously with specified {@link CloudQuery}. * * @param query * {@link CloudQuery} to execute. * @return {@link List} of {@link CloudEntity} of the result. * @throws IOException * When the call had failed for any reason. */ public List<CloudEntity> list(CloudQuery query) throws IOException { // execute the query EntityListDto cbList; QueryDto cq = query.convertToQueryDto(); Log.i(Consts.TAG, "list: executing query: " + cq); cbList = getMBSEndpoint().list(cq).execute(); Log.i(Consts.TAG, "list: result: " + cbList.getEntries()); // convert the result to List List<CloudEntity> coList = new LinkedList<CloudEntity>(); if (cbList.getEntries() != null) { for (EntityDto cd : cbList.getEntries()) { coList.add(CloudEntity.createCloudEntityFromEntityDto(cd)); } } return coList; } }