com.hazelcast.cardinality.impl.operations.MergeOperation Maven / Gradle / Ivy
/*
* Copyright (c) 2008-2020, Hazelcast, Inc. All Rights Reserved.
*
* Licensed 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 com.hazelcast.cardinality.impl.operations;
import com.hazelcast.cardinality.impl.hyperloglog.HyperLogLog;
import com.hazelcast.nio.ObjectDataInput;
import com.hazelcast.nio.ObjectDataOutput;
import com.hazelcast.spi.Operation;
import com.hazelcast.spi.merge.SplitBrainMergePolicy;
import com.hazelcast.spi.merge.SplitBrainMergeTypes.CardinalityEstimatorMergeTypes;
import com.hazelcast.spi.serialization.SerializationService;
import java.io.IOException;
import static com.hazelcast.cardinality.impl.CardinalityEstimatorDataSerializerHook.MERGE;
import static com.hazelcast.spi.impl.merge.MergingValueFactory.createMergingEntry;
/**
* Contains a mergeable {@link HyperLogLog} instance for split-brain healing with a {@link SplitBrainMergePolicy}.
*
* @since 3.10
*/
public class MergeOperation
extends CardinalityEstimatorBackupAwareOperation {
private SplitBrainMergePolicy mergePolicy;
private HyperLogLog value;
private transient HyperLogLog backupValue;
public MergeOperation() {
}
public MergeOperation(String name, SplitBrainMergePolicy mergePolicy,
HyperLogLog value) {
super(name);
this.mergePolicy = mergePolicy;
this.value = value;
}
@Override
public void run() throws Exception {
SerializationService serializationService = getNodeEngine().getSerializationService();
CardinalityEstimatorMergeTypes mergingEntry = createMergingEntry(serializationService, name, value);
backupValue = getCardinalityEstimatorContainer().merge(mergingEntry, mergePolicy, serializationService);
}
@Override
public int getId() {
return MERGE;
}
@Override
public boolean shouldBackup() {
return backupValue != null;
}
@Override
public Operation getBackupOperation() {
return new MergeBackupOperation(name, backupValue);
}
@Override
protected void readInternal(ObjectDataInput in) throws IOException {
super.readInternal(in);
mergePolicy = in.readObject();
value = in.readObject();
}
@Override
protected void writeInternal(ObjectDataOutput out) throws IOException {
super.writeInternal(out);
out.writeObject(mergePolicy);
out.writeObject(value);
}
}