/*
* 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;
/**
* This interface provides a context in which operators can initialize by registering to managed state (i.e. state that
* is managed by state backends) or iterating over streams of state partitions written as raw state in a previous
* snapshot.
*
* <p>
* Similar to the managed state from {@link ManagedInitializationContext} and in general, raw operator state is
* available to all operators, while raw keyed state is only available for operators after keyBy.
*
* <p>
* For the purpose of initialization, the context signals if all state is empty (new operator) or if any state was
* restored from a previous execution of this operator.
*
*/
@PublicEvolving
public interface StateInitializationContext extends FunctionInitializationContext {
/**
* Returns an iterable to obtain input streams for previously stored operator state partitions that are assigned to
* this operator.
*/
Iterable<StatePartitionStreamProvider> getRawOperatorStateInputs();
/**
* Returns an iterable to obtain input streams for previously stored keyed state partitions that are assigned to
* this operator.
*/
Iterable<KeyGroupStatePartitionStreamProvider> getRawKeyedStateInputs();
}