com.hazelcast.crdt.pncounter.operations.AddOperation Maven / Gradle / Ivy
/*
* Copyright (c) 2008-2018, 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.crdt.pncounter.operations;
import com.hazelcast.crdt.CRDTDataSerializerHook;
import com.hazelcast.cluster.impl.VectorClock;
import com.hazelcast.crdt.pncounter.PNCounterImpl;
import com.hazelcast.crdt.pncounter.PNCounterService;
import com.hazelcast.monitor.impl.LocalPNCounterStatsImpl;
import com.hazelcast.nio.ObjectDataInput;
import com.hazelcast.nio.ObjectDataOutput;
import com.hazelcast.spi.impl.MutatingOperation;
import java.io.IOException;
/**
* Addition/subtraction operation for a
* {@link com.hazelcast.crdt.pncounter.PNCounter}.
* The session consistency guarantees are provided by sending a last-observed
* vector clock with each operation. The operation response will contain the
* current replica vector clock.
*/
public class AddOperation extends AbstractPNCounterOperation implements MutatingOperation {
private VectorClock observedTimestamps;
private boolean getBeforeUpdate;
private long delta;
private CRDTTimestampedLong response;
/**
* Creates the addition operation.
*
* @param name the name of the PNCounter
* @param delta the delta to add to the counter value, can be negative
* @param getBeforeUpdate {@code true} if the operation should return the
* counter value before the addition, {@code false}
* if it should return the value after the addition
* @param observedClock previously observed vector clock, may be {@code null}
*/
public AddOperation(String name, long delta, boolean getBeforeUpdate, VectorClock observedClock) {
super(name);
this.delta = delta;
this.getBeforeUpdate = getBeforeUpdate;
this.observedTimestamps = observedClock;
}
public AddOperation() {
}
@Override
public void run() throws Exception {
final PNCounterImpl counter = getPNCounter(observedTimestamps);
response = getBeforeUpdate
? counter.getAndAdd(delta, observedTimestamps)
: counter.addAndGet(delta, observedTimestamps);
updateStatistics();
}
/** Updates the local PN counter statistics */
private void updateStatistics() {
final PNCounterService service = getService();
final LocalPNCounterStatsImpl stats = service.getLocalPNCounterStats(name);
if (delta > 0) {
stats.incrementIncrementOperationCount();
} else if (delta < 0) {
stats.incrementDecrementOperationCount();
}
stats.setValue(getBeforeUpdate ? (response.getValue() + delta) : response.getValue());
}
@Override
public CRDTTimestampedLong getResponse() {
return response;
}
@Override
protected void writeInternal(ObjectDataOutput out) throws IOException {
super.writeInternal(out);
out.writeBoolean(getBeforeUpdate);
out.writeLong(delta);
out.writeObject(observedTimestamps);
}
@Override
protected void readInternal(ObjectDataInput in) throws IOException {
super.readInternal(in);
getBeforeUpdate = in.readBoolean();
delta = in.readLong();
observedTimestamps = in.readObject();
}
@Override
public int getId() {
return CRDTDataSerializerHook.PN_COUNTER_ADD_OPERATION;
}
}