| /** |
| * 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.ambari.view.hive.resources; |
| |
| import org.apache.ambari.view.hive.persistence.IStorageFactory; |
| import org.apache.ambari.view.hive.persistence.Storage; |
| import org.apache.ambari.view.hive.persistence.utils.FilteringStrategy; |
| import org.apache.ambari.view.hive.persistence.utils.Indexed; |
| import org.apache.ambari.view.hive.persistence.utils.ItemNotFound; |
| import org.apache.ambari.view.hive.utils.ServiceFormattedException; |
| |
| import java.util.List; |
| |
| /** |
| * CRUD resource manager |
| * @param <T> Data type with ID |
| */ |
| abstract public class CRUDResourceManager<T extends Indexed> implements IResourceManager<T> { |
| //TODO: refactor: generic parameter gets Fabric for Indexed objects, not objects itself |
| private Storage storage = null; |
| |
| protected final Class<? extends T> resourceClass; |
| protected IStorageFactory storageFabric; |
| |
| /** |
| * Constructor |
| * @param resourceClass model class |
| */ |
| public CRUDResourceManager(Class<? extends T> resourceClass, IStorageFactory storageFabric) { |
| this.resourceClass = resourceClass; |
| this.storageFabric = storageFabric; |
| } |
| // CRUD operations |
| |
| /** |
| * Create operation |
| * @param object object |
| * @return model object |
| */ |
| @Override |
| public T create(T object) { |
| object.setId(null); |
| return this.save(object); |
| } |
| |
| /** |
| * Read operation |
| * @param id identifier |
| * @return model object |
| * @throws org.apache.ambari.view.hive.persistence.utils.ItemNotFound |
| */ |
| @Override |
| public T read(Object id) throws ItemNotFound { |
| T object = null; |
| object = storageFabric.getStorage().load(this.resourceClass, id); |
| if (!checkPermissions(object)) |
| throw new ItemNotFound(); |
| return object; |
| } |
| |
| /** |
| * Read all objects |
| * @param filteringStrategy filtering strategy |
| * @return list of filtered objects |
| */ |
| @Override |
| public List<T> readAll(FilteringStrategy filteringStrategy) { |
| return storageFabric.getStorage().loadAll(this.resourceClass, filteringStrategy); |
| } |
| |
| /** |
| * Update operation |
| * @param newObject new object |
| * @param id identifier of previous object |
| * @return model object |
| * @throws org.apache.ambari.view.hive.persistence.utils.ItemNotFound |
| */ |
| @Override |
| public T update(T newObject, String id) throws ItemNotFound { |
| newObject.setId(id); |
| this.save(newObject); |
| return newObject; |
| } |
| |
| /** |
| * Delete operation |
| * @param resourceId object identifier |
| * @throws org.apache.ambari.view.hive.persistence.utils.ItemNotFound |
| */ |
| @Override |
| public void delete(Object resourceId) throws ItemNotFound { |
| if (!storageFabric.getStorage().exists(this.resourceClass, resourceId)) { |
| throw new ItemNotFound(); |
| } |
| storageFabric.getStorage().delete(this.resourceClass, resourceId); |
| } |
| |
| // UTILS |
| |
| protected T save(T object) { |
| storageFabric.getStorage().store(resourceClass, object); |
| return object; |
| } |
| |
| protected abstract boolean checkPermissions(T object); |
| |
| protected void cleanupAfterErrorAndThrowAgain(Indexed object, ServiceFormattedException e) { |
| try { |
| delete(object.getId()); |
| } catch (ItemNotFound itemNotFound) { |
| throw new ServiceFormattedException("Error in creation, during clean up: " + itemNotFound.toString(), itemNotFound); |
| } |
| throw e; |
| } |
| } |