/*
* Copyright (c) 2008-2017, 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.internal.jmx;
import com.hazelcast.internal.jmx.suppliers.StatsSupplier;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.concurrent.atomic.AtomicLong;
/**
* Provides LocalStats for {@link MapMBean}, {@link MultiMapMBean}, {@link QueueMBean}
* So that statistics are only created in given internal
* @param <T> LocalStats type
*/
public class LocalStatsDelegate<T> {
private volatile T localStats;
private final StatsSupplier<T> supplier;
private final long intervalMs;
private final AtomicLong lastUpdated = new AtomicLong(0);
private final AtomicBoolean inProgress = new AtomicBoolean(false);
public LocalStatsDelegate(StatsSupplier<T> supplier, long intervalSec) {
this.supplier = supplier;
this.intervalMs = TimeUnit.SECONDS.toMillis(intervalSec);
localStats = supplier.getEmpty();
}
public T getLocalStats() {
long delta = System.currentTimeMillis() - lastUpdated.get();
if (delta > intervalMs) {
if (inProgress.compareAndSet(false, true)) {
try {
localStats = supplier.get();
lastUpdated.set(System.currentTimeMillis());
} finally {
inProgress.set(false);
}
}
}
return localStats;
}
}