/*
* 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.flink.runtime.state;
import org.apache.flink.annotation.PublicEvolving;
import org.apache.flink.configuration.Configuration;
import org.apache.flink.configuration.IllegalConfigurationException;
import java.io.IOException;
import java.io.Serializable;
/**
* A factory to create a specific state backend. The state backend creation gets a Configuration
* object that can be used to read further config values.
*
* <p>The state backend factory is typically specified in the configuration to produce a
* configured state backend.
*
* @param <T> The type of the state backend created.
*/
@PublicEvolving
public interface StateBackendFactory<T extends StateBackend> extends Serializable {
/**
* Creates the state backend, optionally using the given configuration.
*
* @param config The Flink configuration (loaded by the TaskManager).
* @return The created state backend.
*
* @throws IllegalConfigurationException
* If the configuration misses critical values, or specifies invalid values
* @throws IOException
* If the state backend initialization failed due to an I/O exception
*/
T createFromConfig(Configuration config) throws IllegalConfigurationException, IOException;
}