I have been trying to come up with a cron expression to start a job at 8.30am and run every 30 mins until midnight and restart at 8.30am next day. I came up with following expression but only thing it lacks is starting at 8.30am. Rather than starting at 8.30 it starts at 8.00.
0 0/30 8/1 * * ?
Is it even possible to do what I'm trying to do? I'll be using java quartz2.x.x
It seems to be not possible in single expression. There is good link, to create your cron expression, you may refer Cron Maker
==Updated==
You can have two cron expression
0 30/30 8 ? * * * //every day 8:30
And,
0 0/30 9-23 * * ? // every 30 min starts from 9:00
来源：https://stackoverflow.com/questions/42966927/quartz-start-at-a-specific-time-and-run-at-specific-interval