How can I run a scheduled process on simple java application?

[wuaner]

Hi,

I have a scenario that need to start a processing instance for every user that registered 5 days ago. Because is more like a scheduled job(but the processing for each user is workflow), so i want to implement it with simple java app + cron(Run every day for users that registered 5 days ago).

But the question is,  how can I trigger the already exist process instances to be continue on cron-triggered simple java app? is Activiti must be run on a Web container, for example, tomcat?

Sorry for my poor English.

Regards.

[trademak]

That depends on the state of the running process instances. Is the current state for example a receive or user task? You can use the Activiti Java API to lookup a process instance and trigger it based on the current state task type. So no, you don't need a web container.

Best regards,

[wuaner]

Hi Tijs, thank you so much for your prompt response!

I am thinking of use timing catching event and service task for subsequent execution. Because there is no human activity involved in the processing(user task), and no message interaction(receive task). I am working on a social network site, here is the brief scenario of my business logic:

For every user NEW_USER that registered 5 days ago:
Use a fake user FAKE_USER_A, sending friend invitation to NEW_USER;
—-3 days later, check the invitation was accepted or not;
——–If yes, use FAKE_USER_A send a message to NEW_USER;
————2 days later, check the message was responded or not;
—————-if yes, use FAKE_USER_A send response-message to NEW_USER;
—————-if not, end;
——–if not, use fake user FAKE_USER_B sending a message to NEW_USER;
————2 days later, check the message was responded or not;
—————-if yes, use FAKE_USER_B send response-message to NEW_USER;
—————-if not, end;

I can not figure out how can I run these scheduled process instances on a cron-triggered simple java application? and this is also a batch processing.

Any response would be greatly appreciated.


Regards.

[jbarrez]

You can have one 'master' process with a start event timer that does these checks regulary.
When conditions are met, it starts new process instances. If not, it just completes.

[wuaner]

Hi jbarrez,
Thank you so much for your response, and sorry for my late reply.
I have one more concern. Because i need start tens of thousands of process instances simultaneously, is workflow engine like Activiti suitable for this? Is there any chances we got pressures on JVM, memory or disk?

[frederikherema1]

Do you mean you want to start 10000+ processes from within the other process?
- If so, this *can* be problematic because the processes will be started in the same transaction as the API-call (or timer-fire) that kicks off that logic. Depends on transaction-size of your DB and can use alot of memory.
- If not (so you're just starting processes using the API in some kind of loop/pool) this is no issue. Engine execution itself has very little overhead in CPU-time. Most time is spent in DB-logic (also optimized to prevent unneeded insert/update/deletes) and user-code offcourse (e.g.. you calling a service). If you disable (or lower the level) of the history, you can limit the DB-writes to a bare minimum.

[wuaner]

Hi frederikheremans,

It's not. I just want to staring 10k+(approximately up to 100k) process instances in loops, as you mentioned in #2. So there is no issue here, thank you so much for clearing things up.

Regards.