Allow to start the Quartz scheduler in halted mode

[gsmet]

Supersedes #14043

/cc @nragon @machi1990

[gsmet]

@mkouba I applied your suggestions and renamed halted to standby. Should be good to go now.

[nragon]

@gsmet (note) not to be confused with quartz standby mode (which can affect behavior on resuming a trigger)

[gsmet]

@nragon so you're saying renaming it to standby is a bad idea?

From my tests, the Quartz scheduler was in standby mode on startup.

[mkouba]

@gsmet (note) not to be confused with quartz standby mode (which can affect behavior on resuming a trigger)

Hm, that's actually a good point. So standby means started but temporarily halted.

By the way, the current io.quarkus.quartz.runtime.QuartzScheduler.isRunning() implementation does not reflect the new start mode because previously an enabled scheduler was always started.

[mkouba]

@nragon so you're saying renaming it to standby is a bad idea?

From my tests, the Quartz scheduler was in standby mode on startup.

It's paused by default (until started): https://github.com/quartz-scheduler/quartz/blob/master/quartz-core/src/main/java/org/quartz/core/QuartzSchedulerThread.java#L123

[gsmet]

By the way, the current io.quarkus.quartz.runtime.QuartzScheduler.isRunning() implementation does not reflect the new start mode because previously an enabled scheduler was always started.

Not sure I understand that? isRunning() returns false if we set the start mode to halted.

[gsmet]

Went back to halted then.

[mkouba]

By the way, the current io.quarkus.quartz.runtime.QuartzScheduler.isRunning() implementation does not reflect the new start mode because previously an enabled scheduler was always started.

Not sure I understand that? isRunning() returns false if we set the start mode to halted.

Yeah, it works because isInStandbyMode() returns true by default - see #14122 (comment)

[nragon]

I was just mentioning that the standby action on quartz implies notifying both job store and listeners.
For me halted means that scheduler was not put on hold but the start was delayed for some reason.

[gsmet]

@nragon yes, makes sense. I went back to your original proposal, sorry for the noise.