org.apache.flink.runtime.state.heap.NestedStateMapSnapshot Maven / Gradle / Ivy
/*
* 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.api.common.typeutils.TypeSerializer;
import org.apache.flink.core.memory.DataOutputView;
import org.apache.flink.runtime.state.StateSnapshotTransformer;
import javax.annotation.Nonnull;
import javax.annotation.Nullable;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;
/**
* This class represents the snapshot of a {@link NestedStateMap}.
*
* @param type of key
* @param type of namespace
* @param type of state
*/
public class NestedStateMapSnapshot
extends StateMapSnapshot> {
/**
* Creates a new {@link NestedStateMapSnapshot}.
*
* @param owningStateMap the {@link NestedStateMap} for which this object represents a snapshot.
*/
public NestedStateMapSnapshot(NestedStateMap owningStateMap) {
super(owningStateMap);
}
@Override
public void writeState(
TypeSerializer keySerializer,
TypeSerializer namespaceSerializer,
TypeSerializer stateSerializer,
@Nonnull DataOutputView dov,
@Nullable StateSnapshotTransformer stateSnapshotTransformer) throws IOException {
Map> mappings = filterMappingsIfNeeded(owningStateMap.getNamespaceMap(), stateSnapshotTransformer);
int numberOfEntries = countMappingsInKeyGroup(mappings);
dov.writeInt(numberOfEntries);
for (Map.Entry> namespaceEntry : mappings.entrySet()) {
N namespace = namespaceEntry.getKey();
for (Map.Entry entry : namespaceEntry.getValue().entrySet()) {
namespaceSerializer.serialize(namespace, dov);
keySerializer.serialize(entry.getKey(), dov);
stateSerializer.serialize(entry.getValue(), dov);
}
}
}
private Map> filterMappingsIfNeeded(
final Map> keyGroupMap,
StateSnapshotTransformer stateSnapshotTransformer) {
if (stateSnapshotTransformer == null) {
return keyGroupMap;
}
Map> filtered = new HashMap<>();
for (Map.Entry> namespaceEntry : keyGroupMap.entrySet()) {
N namespace = namespaceEntry.getKey();
Map filteredNamespaceMap = filtered.computeIfAbsent(namespace, n -> new HashMap<>());
for (Map.Entry keyEntry : namespaceEntry.getValue().entrySet()) {
K key = keyEntry.getKey();
S transformedvalue = stateSnapshotTransformer.filterOrTransform(keyEntry.getValue());
if (transformedvalue != null) {
filteredNamespaceMap.put(key, transformedvalue);
}
}
if (filteredNamespaceMap.isEmpty()) {
filtered.remove(namespace);
}
}
return filtered;
}
private int countMappingsInKeyGroup(final Map> keyGroupMap) {
int count = 0;
for (Map namespaceMap : keyGroupMap.values()) {
count += namespaceMap.size();
}
return count;
}
}