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is it ok that two spring batch job overlaps?

Suppose I have a spring job run every 5 minute, usually the job will take about one minute to complete, but if something goes wrong the job will last more than 5 minute. Before last job finished , another job will start. So, the two jobs will interfere with each other?
ps: I use the spring schedule annotation to schedule jobs.

You can control this behavior. If you want to leave a fixed amount of time between the end of one job and the start of the next, use the fixedDelay http://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/scheduling/annotation/Scheduled.html#fixedDelay--.
If you use the fixedRate, then jobs may overlap. Whether that's "ok" depends on what your job does. But you can prevent this from happening with fixedDelay if you want.

Quartz for iregular interval of hours

I am using Quartz library to schedule Thread (using Jobs).
My boss ask me if it is possible to solve this situation with Quartz:
There is one Process that must be executed only days of the week at 00:00hs, 5:00hs, 9:00hs, and other diferent hours. As you can see, there isn't regular interval of the repeat. There are 5 o 6 different hours.
Is there some ScheduleBuilder to solve this situation?
I tried with DailyTimeIntervalScheduleBuilder but this Schedule work for regular interval of time.

Simple solution is to schedule job every hour. And within the Job check current time to see if it is 00.00 or 05.00 or 09.00. If it is, do your Job, else do nothing.

It's very simple, if you use a CronTrigger , see: http://quartz-scheduler.org/documentation/quartz-1.x/tutorials/crontrigger.
This way you will be able to schedule the job only on specific times, using an expression similar to Unix cron expressions.
For your case, if you like to start a job on each working week day at 0, 5 and 9 hours, you will use an expression like 0 0 0,5,9 ? * MON-FRI

execute job immediately

I try to run emergency job immediately after scheduled with quartz.
my code is below.I give current time as startTime.
Bıt it takes 30- 40 seconds to run job after schedule.How can run immediately.
// Trigger the job to run now, and then repeat every 40 seconds
jobTrigger= newTrigger()
.withIdentity(Long.toString(emergencyJob.getId()), Long.toString(emergencyJob.getVariant().getId()))
.withPriority(emergencyJob.getPriority())
.startAt(new Date(ctime))
.withSchedule(simpleSchedule().withMisfireHandlingInstructionFireNow()
)
.build();
scheduler.scheduleJob(jobDetail, jobTrigger);

You can also fire it with:
scheduler.triggerJob(jobDetail.getKey());

This is just a guess (it's been a while since I've used quartz), but since you create the Date instance before you actually call build(), it may not be able to meet that time constraint and simply fires 40 seconds later when the next scheduled trigger fires. Try something like this to confirm:
.startAt(new Date(System.currentTimeMillis() + 1000))
Play with the 1000ms value to suit your needs. This is to give it a bit more time to meet the first scheduled trigger.

Probably bit late, but maybe someone will find this useful. I had same issue with quartz on JBoss AS (triggers executed late - approximately 20-30 seconds, for no obvious reason). I came to conclusion that this is caused by some bug in JBoss. Same application worked fine on glassfish. I have changed only PU in order to work with eclipse link and other persistence worked fine on JBoss, so I don't suppose issue there. This behaviour occured only when using quartz database task store, with RAM store it worked fine.
To answear the question. If you use database taskstore, consider changing it to RAM store for me that caused triggers to be fired at time.

Complex time schedule for cron job in AppEngine(Java)

I need a cron job to run on every 15 mins in every weekday just
from 8:00 to 16:00.
How to set the Schedule Format for this cron job?

The simplest approach: set it to run every 15 minutes anyway, and then at the very start of your application code just bail out immediately and innocuously if it's not a weekday or the time is too early or late. This will serve you particularly well if and when further complications are involved (this schedule looks suspiciously like "working hours" so it can't be long before somebody asks you to avoid running on Christmas and the like;-).

Take a look at this link which describes how to create a cron expression http://www.quartz-scheduler.org/docs/tutorials/crontrigger.html
It should be something like this for your case 0 0/15 08-16 * * MON-FRI (Not validated)

Quartz job tunning

hello there is something i've realized with quartz when working.Say a cron is set to wake up every 2min with the expression 0 0/2 * * * ? .
When you run the project at say 13:10:30, the first action happens at 13:12:00 and the second 13:14:00 and every 2min 0 second for the rest. Obviously between the startup of the project and the first occurence of the action there have been 1mn:30s only.
Is there a way to for the first occurrence to respect the 2min no matter which at seconds the project starts?

Cron jobs are configured in Quartz using the CronTrigger class. The alternative is to use SimpleTrigger, which you can construct using fixed delay intervals. SimpleTrigger has various constructors, allowing you to specify the start time, end time, number of repeats, repeat interval, and so on.
Having said that, I'd recommend against using Quartz for this kind of scheduling, and use java.util.concurrent.Executors.newScheduledThreadPool(). It's much easier than Quartz when it comes to simple repeating tasks.

Quartz may use cron for the scheduling, which is based on date and time, not duration. This means that the cron expression you define is directly related to the current time on the machine, not on when the application started.
I am not aware of a Quartz configuration that will help you to solve your problem. However, a solution is to create your own Thread, which started during the launch of your application and that basically waits 2 minutes before calling a method:
while (running) {
Thread.sleep(1000 * 120);
doStuff();
}