如何使用spring任务停止计划的作业

Question

I have implemented a sample spring scheduled task, with an applicationContext as follows,

<task:scheduled-tasks scheduler="myScheduler">
    <task:scheduled ref="cron" method="show" cron="0/10 * * * * ?"/>
    <task:scheduled ref="cron" method="show2" cron="0/15 * * * * ?"/>
</task:scheduled-tasks>

<task:scheduler id="myScheduler" pool-size="10"/>

How can I stop this schedule method?

Answer 1

Inject the ThreadPoolTaskScheduler into another bean, and invoke shutdown() . If that isn't acceptable, you could configure the cron bean to accept a flag. For example:

public class Job() {
    private final AtomicBoolean stop = new AtomicBoolean(false);

    public void show() {
        if (stop.get()) {
            return;
        }
        ...
    }

    public void stop() {
        stop.set(true);
    }
}

Note that this won't remove the job from the scheduler. The only way to prevent that would be to obtain a reference to the ScheduledFuture and call cancel() .

Answer 2

Depends on what you mean by "stop".

1. Business Condition Stop: Stop as result of a business condition, you should have those conditions evaluated in your methods and just simply not execute the code. This way you can stop unwanted execution at runtime, run your logic to handle the condition fail (logging,notification,etc) as a result.

2. Non Business Condition: Externalize the chron expression to properties file or as I prefer a system variable in the JVM. Then you can just change the property value to a 9999 scenario to stop any execution.

System Variable Example.

<task:scheduled-tasks scheduler="myScheduler">
<task:scheduled ref="cron" method="show" cron="#{systemProperties['chron1']}"/>
<task:scheduled ref="cron" method="show2" cron="#{systemProperties['chron2']}"/>