org.apache.flink.streaming.api.operators.sorted.state.MergingAbstractBatchExecutionKeyState 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.streaming.api.operators.sorted.state;
import org.apache.flink.api.common.typeutils.TypeSerializer;
import org.apache.flink.runtime.state.internal.InternalMergingState;
import java.util.Collection;
/**
* An abstract class with a common implementation of {@link
* InternalMergingState#mergeNamespaces(Object, Collection)}.
*/
abstract class MergingAbstractBatchExecutionKeyState
extends AbstractBatchExecutionKeyState
implements InternalMergingState {
protected MergingAbstractBatchExecutionKeyState(
V defaultValue,
TypeSerializer keySerializer,
TypeSerializer namespaceSerializer,
TypeSerializer stateTypeSerializer) {
super(defaultValue, keySerializer, namespaceSerializer, stateTypeSerializer);
}
protected abstract V merge(V target, V source) throws Exception;
@Override
public void mergeNamespaces(N target, Collection sources) throws Exception {
if (sources == null || sources.isEmpty()) {
return;
}
setCurrentNamespace(target);
V targetValue = getCurrentNamespaceValue();
for (N source : sources) {
setCurrentNamespace(source);
V sourceValue = getCurrentNamespaceValue();
if (targetValue == null) {
targetValue = sourceValue;
} else if (sourceValue != null) {
targetValue = merge(targetValue, sourceValue);
clear();
}
}
setCurrentNamespace(target);
setCurrentNamespaceValue(targetValue);
}
@Override
public V getInternal() {
return getCurrentNamespaceValue();
}
@Override
public void updateInternal(V valueToStore) {
setCurrentNamespaceValue(valueToStore);
}
}