com.aspectran.core.component.session.HouseKeeper Maven / Gradle / Ivy
/*
* Copyright (c) 2008-2022 The Aspectran Project
*
* 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.aspectran.core.component.session;
import com.aspectran.core.util.ToStringBuilder;
import com.aspectran.core.util.lifecycle.AbstractLifeCycle;
import com.aspectran.core.util.logging.Logger;
import com.aspectran.core.util.logging.LoggerFactory;
import com.aspectran.core.util.thread.AutoLock;
import com.aspectran.core.util.thread.Scheduler;
import java.util.concurrent.TimeUnit;
/**
* The housekeeper for session scavenging.
* There is 1 session HouseKeeper per SessionManager instance.
*/
public class HouseKeeper extends AbstractLifeCycle {
private static final Logger logger = LoggerFactory.getLogger(HouseKeeper.class);
public static final long DEFAULT_SCAVENGING_INTERVAL_MS = 1000L * 60 * 10;
private final AutoLock lock = new AutoLock();
private final SessionHandler sessionHandler;
private final Scheduler scheduler;
private Scheduler.Task task; // scavenge task
private Runner runner;
/** 10 minute default */
private long scavengingInterval = DEFAULT_SCAVENGING_INTERVAL_MS;
/**
* @param sessionHandler SessionHandler associated with this scavenger
*/
public HouseKeeper(SessionHandler sessionHandler) {
this.sessionHandler = sessionHandler;
this.scheduler = sessionHandler.getScheduler();
}
/**
* Get the period between scavenge cycles.
* @return the interval (in seconds)
*/
public int getScavengingInterval() {
return (int)(scavengingInterval / 1000L);
}
/**
* Set the period between scavenge cycles.
* @param intervalInSecs the interval (in seconds)
*/
public void setScavengingInterval(int intervalInSecs) {
try (AutoLock ignored = lock.lock()) {
if (isStarted() || isStarting()) {
if (intervalInSecs <= 0) {
scavengingInterval = 0L;
logger.info("Scavenging disabled");
stopScavenging();
} else {
if (intervalInSecs < 10) {
logger.warn("Short interval of " + intervalInSecs + " secs for session scavenging");
}
scavengingInterval = intervalInSecs * 1000L;
if (isStarting() || isStarted()) {
startScavenging();
}
}
} else {
scavengingInterval = intervalInSecs * 1000L;
}
}
}
/**
* If scavenging is not scheduled, schedule it.
*/
protected void startScavenging() {
try (AutoLock ignored = lock.lock()) {
// cancel any previous task
if (task != null) {
task.cancel();
}
if (runner == null) {
runner = new Runner();
}
logger.info(sessionHandler.getComponentName() + " Scavenging every " + scavengingInterval + " ms");
task = scheduler.schedule(runner, scavengingInterval, TimeUnit.MILLISECONDS);
}
}
/**
* If scavenging is scheduled, stop it.
*/
protected void stopScavenging() {
try (AutoLock ignored = lock.lock()) {
if (task != null) {
task.cancel();
logger.info(sessionHandler.getComponentName() + " Stopped scavenging");
}
task = null;
runner = null;
}
}
/**
* Periodically do session housekeeping.
*/
private void scavenge() {
// don't attempt to scavenge if we are shutting down
if (isStopping() || isStopped()) {
return;
}
try {
sessionHandler.scavenge();
} catch (Exception e) {
logger.warn(e);
}
}
@Override
protected void doStart() throws Exception {
setScavengingInterval(getScavengingInterval());
super.doStart();
}
@Override
protected void doStop() throws Exception {
stopScavenging();
super.doStop();
}
@Override
public String toString() {
ToStringBuilder tsb = new ToStringBuilder(super.toString());
tsb.append("scavengingInterval", scavengingInterval);
return tsb.toString();
}
/**
* Runner
*/
private class Runner implements Runnable {
@Override
public void run() {
try {
scavenge();
} finally {
try (AutoLock ignored = lock.lock()) {
if (scheduler != null && scheduler.isRunning()) {
task = scheduler.schedule(this, scavengingInterval, TimeUnit.MILLISECONDS);
}
}
}
}
}
}