| /** |
| * 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. |
| */ |
| |
| /** |
| * The state store uses modular data storage classes derived from |
| * StateStoreDriver to handle querying, updating and deleting data records. The |
| * data storage driver is initialized and maintained by the StateStoreService. |
| * The state store supports fetching all records of a type, filtering by column |
| * values or fetching a single record by its primary key. |
| * <p> |
| * Each data storage backend is required to implement the methods contained in |
| * the StateStoreDriver interface. These methods allow the querying, updating, |
| * inserting and deleting of data records into the state store. |
| */ |
| |
| @InterfaceAudience.Private |
| @InterfaceStability.Evolving |
| |
| package org.apache.hadoop.hdfs.server.federation.store.driver; |
| |
| import org.apache.hadoop.classification.InterfaceAudience; |
| import org.apache.hadoop.classification.InterfaceStability; |