jodd.cache.TimedCache Maven / Gradle / Ivy
// Copyright (c) 2003-present, Jodd Team (http://jodd.org)
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//
// 1. Redistributions of source code must retain the above copyright notice,
// this list of conditions and the following disclaimer.
//
// 2. Redistributions in binary form must reproduce the above copyright
// notice, this list of conditions and the following disclaimer in the
// documentation and/or other materials provided with the distribution.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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// POSSIBILITY OF SUCH DAMAGE.
package jodd.cache;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Timer;
import java.util.TimerTask;
/**
* Timed cache. Not limited by size, objects are removed only when they are expired.
* Prune is not invoked explicitly by standard {@link Cache} methods, however,
* it is possible to schedule prunes on fined-rate delays.
*/
public class TimedCache extends AbstractCacheMap {
public TimedCache(final long timeout) {
this.cacheSize = 0;
this.timeout = timeout;
cacheMap = new HashMap<>();
}
// ---------------------------------------------------------------- prune
/**
* Prunes expired elements from the cache. Returns the number of removed objects.
*/
@Override
protected int pruneCache() {
int count = 0;
Iterator> values = cacheMap.values().iterator();
while (values.hasNext()) {
CacheObject co = values.next();
if (co.isExpired()) {
values.remove();
count++;
}
}
return count;
}
// ---------------------------------------------------------------- auto prune
protected Timer pruneTimer;
/**
* Schedules prune.
*/
public void schedulePrune(final long delay) {
if (pruneTimer != null) {
pruneTimer.cancel();
}
pruneTimer = new Timer();
pruneTimer.schedule(
new TimerTask() {
@Override
public void run() {
prune();
}
}, delay, delay
);
}
/**
* Cancels prune schedules.
*/
public void cancelPruneSchedule() {
if (pruneTimer != null) {
pruneTimer.cancel();
pruneTimer = null;
}
}
}