/**
* Copyright 2003-2010 Terracotta, Inc.
*
* 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 net.sf.ehcache.util.counter;
import java.util.ArrayList;
import java.util.List;
import net.sf.ehcache.util.FailSafeTimer;
import net.sf.ehcache.util.counter.sampled.SampledCounter;
import net.sf.ehcache.util.counter.sampled.SampledCounterImpl;
/**
* An implementation of a {@link CounterManager}.
*
* @author <a href="mailto:asanoujam@terracottatech.com">Abhishek Sanoujam</a>
* @since 1.7
*
*/
public class CounterManagerImpl implements CounterManager {
private FailSafeTimer timer;
private boolean shutdown;
private List<Counter> counters = new ArrayList<Counter>();
/**
* Constructor that accepts a timer that will be used for scheduling sampled
* counter if any is created
*/
public CounterManagerImpl(FailSafeTimer timer) {
if (timer == null) {
throw new IllegalArgumentException("Timer cannot be null");
}
this.timer = timer;
}
/**
* {@inheritDoc}
*/
public synchronized void shutdown() {
if (shutdown) {
return;
}
try {
// do not cancel the timer as others might also be using it
// instead shutdown the counters of this counterManager
for (Counter counter : counters) {
if (counter instanceof SampledCounter) {
((SampledCounter) counter).shutdown();
}
}
} finally {
shutdown = true;
}
}
/**
* {@inheritDoc}
*/
public synchronized Counter createCounter(CounterConfig config) {
if (shutdown) {
throw new IllegalStateException("counter manager is shutdown");
}
if (config == null) {
throw new NullPointerException("config cannot be null");
}
Counter counter = config.createCounter();
if (counter instanceof SampledCounterImpl) {
SampledCounterImpl sampledCounter = (SampledCounterImpl) counter;
timer.schedule(sampledCounter.getTimerTask(), sampledCounter.getIntervalMillis(), sampledCounter.getIntervalMillis());
}
counters.add(counter);
return counter;
}
/**
* {@inheritDoc}
*/
public void shutdownCounter(Counter counter) {
if (counter instanceof SampledCounter) {
SampledCounter sc = (SampledCounter) counter;
sc.shutdown();
}
}
}