com.hazelcast.map.merge.LatestUpdateMapMergePolicy Maven / Gradle / Ivy
/*
* Copyright (c) 2008-2013, 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.map.merge;
import com.hazelcast.core.EntryView;
import com.hazelcast.nio.ObjectDataInput;
import com.hazelcast.nio.ObjectDataOutput;
import java.io.IOException;
/**
* LatestUpdateMapMergePolicy causes the merging entry to be merged from source to destination map
* if source entry has updated more recently than the destination entry.
*
* This policy can only be used of the clocks of the machines are in sync.
*/
public class LatestUpdateMapMergePolicy implements MapMergePolicy {
@Override
public Object merge(String mapName, EntryView mergingEntry, EntryView existingEntry) {
if (mergingEntry.getLastUpdateTime() >= existingEntry.getLastUpdateTime()) {
return mergingEntry.getValue();
}
return existingEntry.getValue();
}
@Override
public void writeData(ObjectDataOutput out) throws IOException {
}
@Override
public void readData(ObjectDataInput in) throws IOException {
}
}