PersisterTask.java
/*
* Copyright (C) 2003-2014 eXo Platform SAS.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package org.exoplatform.forum.common.persister;
import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.ThreadFactory;
import java.util.concurrent.TimeUnit;
import org.exoplatform.services.log.ExoLogger;
import org.exoplatform.services.log.Log;
public class PersisterTask implements PersistAlgorithm {
protected static final Log LOG = ExoLogger.getLogger(PersisterTask.class);
/** */
final Persister persister;
/** */
final long wakeupInterval;
/** */
final Task task;
/** */
final TimeUnit timeUnit;
/** */
final long maxFixedSize;
/** */
ScheduledExecutorService scheduledExecutor;
public static Builder init() {
return new Builder();
}
public PersisterTask(Builder builder) {
this.wakeupInterval = builder.wakeupInterval;
this.maxFixedSize = builder.maxFixedSize;
this.persister = builder.persister;
this.timeUnit = builder.timeUnit == null ? TimeUnit.MILLISECONDS : builder.timeUnit;
this.task = new Task();
}
public void start() {
ThreadFactory threadFactory = new ThreadFactory() {
public Thread newThread(Runnable runable) {
Thread t = new Thread(runable, "Forum-task-thread");
t.setPriority(Thread.MIN_PRIORITY);
return t;
}
};
scheduledExecutor = Executors.newSingleThreadScheduledExecutor(threadFactory);
scheduledExecutor.scheduleWithFixedDelay(task, wakeupInterval / 2, wakeupInterval, this.timeUnit);
}
public void stop() {
if (scheduledExecutor != null) {
scheduledExecutor.shutdownNow();
}
scheduledExecutor = null;
}
public class Task implements Runnable {
public void run() {
try {
persister.commit(true);
} catch (Exception e) {
LOG.error("Persist task encountered an unexpected error", e);
}
}
}
public static class Builder {
public Persister persister;
public long wakeupInterval;
public TimeUnit timeUnit;
public long maxFixedSize;
public Builder() {}
public Builder persister(Persister persister) {
this.persister = persister;
return this;
}
public Builder wakeup(long interval) {
this.wakeupInterval = interval;
return this;
}
public Builder timeUnit(TimeUnit timeUnit) {
this.timeUnit = timeUnit;
return this;
}
public Builder maxFixedSize(long maxFixedSize) {
this.maxFixedSize = maxFixedSize;
return this;
}
public PersisterTask build() {
return new PersisterTask(this);
}
}
@Override
public boolean shoudldPersist(int changedSize) {
return changedSize >= maxFixedSize;
}
}