Make it possible to disable Scheduled job via cron expression [SPR-16858]

Nikolay Bogdanov opened SPR-16858 and commented

To disable a spring job which uses cron expression you need at least 2 properties:

    ...
    @Value("${jobs.name.enable}")
    private boolean jobEnable;

    @Scheduled(cron = "0 0 0 1 * ?")
    public void execute() \{
        if(jobEnable){
            //JOB HERE
        }
    }
    ...
}

But there is no way to configure it to don’t start any execution at all, but its relatively valuable feature (you can google it, but here is an example https://stackoverflow.com/questions/13835221/quartz-cron-expression-that-will-never-execute)

So the idea of this issue is to enable support for some “never” value for cron expression which will prevent this job from execution forever, so you can use only 1 parameter to configure your job. Example:

 
@Scheduled(cron = "never")

The exact value to disable a job is negotiable.

---

Affects: 5.0.6

Referenced from: commits https://github.com/spring-projects/spring-framework/commit/3a5def047f2aeb8b01d94febdabb52c013c1f676

[spring-projects-issues]

Juergen Hoeller commented

I’ve implemented this with a simple skip check in processScheduled if the cron value is “-” (the new Scheduled.CRON_DISABLED constant). This seems quite aligned with cron’s symbolic nature. Any issues with that choice from your side?

[spring-projects-issues]

Nikolay Bogdanov commented

Nice, so paragraph 2 is very similar to the original description of the ticket, right?  Juergen Hoeller do you need some help here to resolve it?