org.apache.flink.runtime.state.heap.CopyOnWriteStateTableSnapshot Maven / Gradle / Ivy
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* 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.heap;
import org.apache.flink.annotation.Internal;
import org.apache.flink.api.common.typeutils.TypeSerializer;
import org.apache.flink.runtime.state.StateSnapshotTransformer;
import javax.annotation.Nonnull;
import java.util.List;
/**
* This class represents the snapshot of a {@link CopyOnWriteStateTable} and has a role in operator state checkpointing.
* This class is also responsible for writing the state in the process of checkpointing.
*
* @param type of key
* @param type of namespace
* @param type of state
*/
@Internal
public class CopyOnWriteStateTableSnapshot extends AbstractStateTableSnapshot {
/**
* The offset to the contiguous key groups.
*/
private final int keyGroupOffset;
/**
* Snapshots of state partitioned by key-group.
*/
@Nonnull
private final List> stateMapSnapshots;
/**
* Creates a new {@link CopyOnWriteStateTableSnapshot}.
*
* @param owningStateTable the {@link CopyOnWriteStateTable} for which this object represents a snapshot.
*/
CopyOnWriteStateTableSnapshot(
CopyOnWriteStateTable owningStateTable,
TypeSerializer localKeySerializer,
TypeSerializer localNamespaceSerializer,
TypeSerializer localStateSerializer,
StateSnapshotTransformer stateSnapshotTransformer) {
super(owningStateTable,
localKeySerializer,
localNamespaceSerializer,
localStateSerializer,
stateSnapshotTransformer);
this.keyGroupOffset = owningStateTable.getKeyGroupOffset();
this.stateMapSnapshots = owningStateTable.getStateMapSnapshotList();
}
@Override
protected StateMapSnapshot> getStateMapSnapshotForKeyGroup(int keyGroup) {
int indexOffset = keyGroup - keyGroupOffset;
CopyOnWriteStateMapSnapshot stateMapSnapshot = null;
if (indexOffset >= 0 && indexOffset < stateMapSnapshots.size()) {
stateMapSnapshot = stateMapSnapshots.get(indexOffset);
}
return stateMapSnapshot;
}
}