Java tutorial
/* * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF licenses this file * to you 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 org.apache.shindig.social.opensocial.service; import java.util.List; import java.util.Set; import java.util.concurrent.Future; import com.google.common.base.Objects; import org.apache.shindig.config.ContainerConfig; import org.apache.shindig.protocol.HandlerPreconditions; import org.apache.shindig.protocol.Operation; import org.apache.shindig.protocol.ProtocolException; import org.apache.shindig.protocol.RequestItem; import org.apache.shindig.protocol.Service; import org.apache.shindig.social.opensocial.model.Album; import org.apache.shindig.social.opensocial.spi.AlbumService; import org.apache.shindig.social.opensocial.spi.CollectionOptions; import org.apache.shindig.social.opensocial.spi.UserId; import com.google.common.collect.ImmutableSet; import com.google.common.collect.Iterables; import com.google.inject.Inject; /** * Receives and delegates requests to the OpenSocial Album service. * * @since 2.0.0 */ @Service(name = "albums", path = "/{userId}+/{groupId}/{albumId}+") public class AlbumHandler { private final AlbumService service; private final ContainerConfig config; @Inject public AlbumHandler(AlbumService service, ContainerConfig config) { this.service = service; this.config = config; } /* * Handles create operations. * * Allowed end-points: /albums/{userId}/@self * * Examples: /albums/john.doe/@self */ @Operation(httpMethods = "POST", bodyParam = "album") public Future<?> create(SocialRequestItem request) throws ProtocolException { // Retrieve userIds and albumIds Set<UserId> userIds = request.getUsers(); List<String> albumIds = request.getListParameter("albumId"); // Preconditions - exactly one userId specified, no albumIds specified HandlerPreconditions.requireNotEmpty(userIds, "No userId specified"); HandlerPreconditions.requireSingular(userIds, "Multiple userIds not supported"); HandlerPreconditions.requireEmpty(albumIds, "Cannot specify albumId in create"); return service.createAlbum(Iterables.getOnlyElement(userIds), request.getAppId(), request.getTypedParameter("album", Album.class), request.getToken()); } /* * Handles retrieve operations. * * Allowed end-points: /albums/{userId}+/{groupId}/{albumId}+ * * Examples: /albums/@me/@self /albums/john.doe/@self/1,2 * /albums/john.doe,jane.doe/@friends */ @Operation(httpMethods = "GET") public Future<?> get(SocialRequestItem request) throws ProtocolException { // Get user, group, and album IDs Set<UserId> userIds = request.getUsers(); Set<String> optionalAlbumIds = ImmutableSet.copyOf(request.getListParameter("albumId")); // At least one userId must be specified HandlerPreconditions.requireNotEmpty(userIds, "No userId specified"); // If multiple userIds specified, albumIds must not be specified if (userIds.size() > 1 && !optionalAlbumIds.isEmpty()) { throw new IllegalArgumentException("Cannot fetch same albumIds for multiple userIds"); } // Retrieve albums by ID if (!optionalAlbumIds.isEmpty()) { if (optionalAlbumIds.size() == 1) { return service.getAlbum(Iterables.getOnlyElement(userIds), request.getAppId(), request.getFields(), optionalAlbumIds.iterator().next(), request.getToken()); } else { return service.getAlbums(Iterables.getOnlyElement(userIds), request.getAppId(), request.getFields(), new CollectionOptions(request), optionalAlbumIds, request.getToken()); } } // Retrieve albums by group return service.getAlbums(userIds, request.getGroup(), request.getAppId(), request.getFields(), new CollectionOptions(request), request.getToken()); } /* * Handles update operations. * * Allowed end-points: /albums/{userId}/@self/{albumId} * * Examples: /albums/john.doe/@self/1 */ @Operation(httpMethods = "PUT", bodyParam = "album") public Future<?> update(SocialRequestItem request) throws ProtocolException { // Retrieve userIds and albumIds Set<UserId> userIds = request.getUsers(); List<String> albumIds = request.getListParameter("albumId"); // Enforce preconditions - exactly one user and one album specified HandlerPreconditions.requireNotEmpty(userIds, "No userId specified"); HandlerPreconditions.requireSingular(userIds, "Multiple userIds not supported"); HandlerPreconditions.requireNotEmpty(albumIds, "No albumId specified"); HandlerPreconditions.requireSingular(albumIds, "Multiple albumIds not supported"); return service.updateAlbum(Iterables.getOnlyElement(userIds), request.getAppId(), request.getTypedParameter("album", Album.class), Iterables.getOnlyElement(albumIds), request.getToken()); } /* * Handles delete operations. * * Allowed end-points: /albums/{userId}/@self/{albumId} * * Examples: /albums/john.doe/@self/1 */ @Operation(httpMethods = "DELETE") public Future<?> delete(SocialRequestItem request) throws ProtocolException { // Get user and album ID Set<UserId> userIds = request.getUsers(); String albumId = request.getParameter("albumId"); // Enforce preconditions - userIds must contain exactly one element HandlerPreconditions.requireNotEmpty(userIds, "No userId specified"); HandlerPreconditions.requireSingular(userIds, "Multiple userIds not supported"); // Service request return service.deleteAlbum(Iterables.getOnlyElement(userIds), request.getAppId(), albumId, request.getToken()); } /* * Retrieves supported fields for the albums service. */ @Operation(httpMethods = "GET", path = "/@supportedFields") public List<Object> supportedFields(RequestItem request) { String container = Objects.firstNonNull(request.getToken().getContainer(), ContainerConfig.DEFAULT_CONTAINER); return config.getList(container, "${Cur['gadgets.features'].opensocial.supportedFields.album}"); } }