ActiveMQ: Cron expression for last day of the every month - cron

Since ,I have use this cron expression "0 0 L * *" for creating scheduled job in activeMQ. but it throws an exception illustrating "when trying to send:For input string: "L"".
Please suggest any other way to scheduled job for every Month in ActiveMQ.
I'm using ActiveMq version 5.8.
Thanks in Advance.

The Cron parser in ActiveMQ is fairly limited in comparison to a real CronTab implementation. I think the error indicates that support for the special characters such as 'L' is not there.
You can always download the code and give it a once over and see if you can improve it with a pull request.

Related

Mulesoft - Need help in creating cron expression for Mule scheduler job application

I need help in creating cron expression for Mule scheduler job.
Scenario : Job should run in every month from 3rd day to 6th day for every 2 hours(intra day) and those days should be working days(Monday to Friday only).
I tried below cron expression in cronMaker : 0 0 7-20/2 3-5 * Mon-Fri *
Here i am getting error for this above expression.
Please help me to resolve this issue. Thank you in Advance.
If you try the same cron expression in an actual Mule application -I used Mule runtime 4.3- using a Scheduler source you will get the following error:
Support for specifying both a day-of-week AND a day-of-month parameter is not implemented.
This is a limitation of the Quartz library that the Scheduler uses in its implementation. This means it is not possible to use that kind of cron expression in a Mule Scheduler, or a Quartz Java application.
Likely CronMaker has the same limitation but it is not showing the full error message.
Updated:
You can avoid the limitation by using only one of the conditions, for example day-of-month (it will trigger less activations) and at the beginning of the flow add a choice with a condition to check for the day of the week using a DataWeave expression. With the choice you can avoid executing the rest of the flow if it is not the right day.
There are no other similar flow source components that I'm aware of. You can try to create your own in Java using Mule SDK.

Hangfire Cron expressions are not valid

I am using Hangfire and I want to describe different scenarios for my RecurringJobs. But I am not being able to achieve what I am looking for, and if CRON is already limited, the CRON used by Hangfire is yet more.
I went on reading Hangfire documentation and I find a like to https://en.wikipedia.org/wiki/Cron#CRON_expression for more complex expressions then the ones supported by default on Hangfire. But they are not even compatible, for instance, Hangfire only has minutes, hour, month, day, days of the week, but if I use the L or the ? on the day like it says on the documentation it does not work. I have this error the following error for this expression 16 14 L ? ?:
InnerException = {"'L' is not a valid [Day] crontab field value. It must be a numeric value between 1 and 31 (all inclusive)."}
CRON from Hangfire has the following method: Monthly(int day); What happens If I choose for instance 31? It will still run on months like February or April for instance at the last day of each month? Or do I need to do something extra to achieve it?
That way what is happening? I do not seem able to define the condition of the day chosen by the user is 31, to run the background jobs always on the last day of the month. And I don't even talk about days 29 or 30 which are also special causes and which I would use always the last day of the month to process the background job.
I though of using the Month method from Hangfire.CRON but I don't think it will treat the days 29,30 and 31 the way I want.
Do you confirm that Hangfire Cron does not use the Cron expressions that are referenced by documentation and if there is any way to achieve what I am looking for? Also, any suggested tutorial or something to help me out? I have been reading https://github.com/atifaziz/NCrontab which I think it is the one Hangfire uses, but it does not help that much.
You are right about NCrontab. Hangfire uses it, so you should ensure your cron expression is supported by this library. Two simple options to do it:
C# Interactive window (as described in NCrontab Readme, or you could use this example )
Online cron visualizer (like https://crontab.guru or http://cron.schlitt.info)
Cron.Monthly(31) is translated to 0 0 31 * * and job would be triggered only if current month has 31 days.
To run the background job always on the last day of the month, add three separate jobs:
0 0 30 4,6,9,11 *
0 0 31 1,3,5,7,8,10,12 *
0 0 28 2 *
Cron job to run on the last day of the month

OOZIE CRON Scheduler

How to get list of next materialized times for oozie coordinator if we have scheduled it frequency using CRON.
In HUE i can see the next materialized time only, I want a list of all the time it will run.
Thank you.
Oozie doesn't give you that list nor provide tools to calculate it.
I usually convert my expression CRON syntax and check with this http://www.cronmaker.com/. This is not a solid answer to your question but at least gives you the execution frequency.
rest syntax
curl http://www.cronmaker.com/rest/sampler?expression={expression}
sample with rest api
http://www.cronmaker.com/rest/sampler?expression=0%200/2%20*%201/1%20*%20?%20*

Creating Cron Expression with of Days and Months Simultaneously

I simply want to create a cron expression that will execute a job after 'N' number of days. Where N can be any number greater than Zero.
So, It's alright if number is between 1 and 30. For Example Cron Expression to Execute Job after each
25 days at 11 AM will be:
0 0 11 1/25 * ? //'?' can only be specfied for Day-of-Month or Day-of-Week.
but if user exceeds this limit so it means we will have to execute job after 'M' months and 'D' days.
I am unable to understand how I can specify both day and month at the same time. Can anyone make me understand how I can create cron expression for this scenario. You may assume job to be execute after each '65' days
thanks for your time.
The short answer is that cron expressions don't support what you want to do. You'll need to pre-process the user's request and convert it into the appropriate cron expression, or implement your own timing routine, which could use cron behind the scene with some extra logic. Another suggestion is to put some restrictions on the user API that will only allow the user to enter cron friendly times like every month, every week, every 3 months, etc.

Quartz Cron job required that executes at 12 am every 2 weeks

http://www.cronmaker.com/
I am using the above link and trying to create a cron job which runs at 12AM on the server every 2 weeks. Could anyone help.
Regards
Nikhil
After a google search I found this, maybe it can help you:
https://coderwall.com/p/yzzu5a
Because you've tagged your question with quartz-scheduler, I assume that you are using Quartz.
You can use the CalendarIntervalScheduleBuilder to set an interval of days, weeks, months, etc.
ScheduleBuilder schb = CalendarIntervalScheduleBuilder.calendarIntervalSchedule().withIntervalInWeeks(2);
Trigger trigger = TriggerBuilder.newTrigger().startAt(DateBuilder.todayAt(0, 0, 0)).withSchedule(schb).forJob(muJob).build();
Here we are telling quartz to run our job every 2 weeks, starting today at 00:00:00 (12 :00 AM ?)
If you insist on using cron style jobs , this might be helpful : http://www.fclose.com/1199/how-to-run-a-cron-job-every-two-weeks-months-days/

Resources