| /** |
| * 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 |
| * <p> |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * <p> |
| * 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.kafka.streams.processor; |
| |
| /** |
| * A storage engine for managing state maintained by a stream processor. |
| * |
| * <p> |
| * This interface does not specify any query capabilities, which, of course, |
| * would be query engine specific. Instead it just specifies the minimum |
| * functionality required to reload a storage engine from its changelog as well |
| * as basic lifecycle management. |
| * </p> |
| */ |
| public interface StateStore { |
| |
| /** |
| * The name of this store. |
| * @return the storage name |
| */ |
| String name(); |
| |
| /** |
| * Initializes this state store |
| */ |
| void init(ProcessorContext context, StateStore root); |
| |
| /** |
| * Flush any cached data |
| */ |
| void flush(); |
| |
| /** |
| * Close the storage engine |
| */ |
| void close(); |
| |
| /** |
| * Return if the storage is persistent or not. |
| * |
| * @return {@code true} if the storage is persistent—{@code false} otherwise |
| */ |
| boolean persistent(); |
| } |