/
OptimisticStampedCounter.java
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/
OptimisticStampedCounter.java
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/*
* Copyright 2016 M. Isuru Tharanga Chrishantha Perera
*
* 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.github.chrishantha.microbenchmark.counter.impl;
import com.github.chrishantha.microbenchmark.counter.Counter;
import java.util.concurrent.locks.StampedLock;
public class OptimisticStampedCounter implements Counter {
private StampedLock rwlock = new StampedLock();
private long counter;
public long getCount() {
long stamp = rwlock.tryOptimisticRead();
long currentCount;
if (rwlock.validate(stamp)) {
currentCount = counter;
} else {
stamp = rwlock.readLock();
try {
currentCount = counter;
} finally {
rwlock.unlockRead(stamp);
}
}
return currentCount;
}
public void increment() {
long stamp = rwlock.writeLock();
try {
++counter;
} finally {
rwlock.unlockWrite(stamp);
}
}
}