服务器关闭后自动重新调度作业

Question

The requirement is simple, say server need to set variable salesOffRatio to 0.8 between 01-01 and 01-10 total ten days. And "salesOffRatio = 0.8" is a job which triggered by a quartz trigger at 01-10 00:00:00. The problem is server restart at 01-05 due to power lack, variable salesOffRatio will be not 0.8 anymore, it will become to init value and the trigger will not fire because 01-10 00:00:00 has been passed.

Is there a solution to solve this kind problem? I need auto re-schedule because the job need to set a state for a very long duration and server have to restart in that duration due to maintain operation or something like that which can not be avoid.

misfire with jdbcJobStore seems ok, set a proper misfire threshold. But it is universal, in this situation, I need to set distinct value for each job ( salesOffRatio1, salesOffRatio2...)

Answer 1

Few solutions I came up with:

1. Your salesOffRatio should survive server restart. Store it in a database, file, whatever. Instead of modifying the variable, update your database in a job.

2. If your use-case is so simple, why not create a function

    double getSalesOffRatio(Date effectiveDate) 

   that will return correct salesOffRatio value depending on effectiveDate passed? In other words just compute salesOffRatio every time you need it. BTW the extra argument will make testing easier compared to reading current system time inside getSalesOffRatio() .

3. You can use XML scheduling plugin or some other way to reschedule all jobs every time server restarts. By default job is deleted after it was triggered ( durable property) so by carefully configuring misfire policy, scheduler will refire all your jobs on startup. Brittle in my opinion.

Final thought: talking about misfire policies, have you considered what will happen if restart occurs when the job was scheduled ?

Answer 2

Either you could persist the value of 'salesOffRatio' to a database or a file, and then rather than initialising it to a default value, you could initialise it to the stored value.

Alternatively you could run a program on startup to re-run all quartz triggers (or just those in the jobgroup which you need for updating these values).