package com.github.knightliao.apollo.redis.eviction;
import java.util.Timer;
import java.util.TimerTask;
import java.util.concurrent.atomic.AtomicInteger;
/**
* EvictionTimer
*
* @author zhangxu04
*/
public class EvictionTimer {
private static Timer timer;
private static AtomicInteger usageCount = new AtomicInteger(0);
private EvictionTimer() {
// Hide the default constuctor
}
/**
* Add the specified eviction task to the timer. Tasks that are added with a call to this method *must* call
* {@link #cancel(java.util.TimerTask)} to cancel the task to prevent memory and/or thread leaks in application
* server
* environments.
*
* @param task Task to be scheduled
* @param evictorDelayCheckSeconds Delay in milliseconds before task is executed
* @param evictorCheckPeriodSeconds Time in milliseconds between executions
*/
public static synchronized void schedule(TimerTask task, int evictorDelayCheckSeconds,
int evictorCheckPeriodSeconds) {
if (null == timer) {
timer = new Timer(true);
}
usageCount.incrementAndGet();
timer.schedule(task, evictorDelayCheckSeconds * 1000, evictorCheckPeriodSeconds * 1000);
}
/**
* Remove the specified eviction task from the timer.
*
* @param task Task to be scheduled
*/
public static synchronized void cancel(TimerTask task) {
if (task == null) {
return;
}
task.cancel();
usageCount.decrementAndGet();
if (usageCount.get() == 0) {
timer.cancel();
timer = null;
}
}
}
