Scheduler in Java

Question

I need some assistance in implementing a scheduler which runs parallel with the other processing. I found quartz scheduler for many of my searches on the web. But, I need something which is inbuilt and can run concurrently with other processes and not any external libraries

I checked with scheduleAtFixedRate. But, this has not option for parallel execution.

Can anyone please suggest in this regard?? My requirement is that, a java function has to run at every fixed intervals soon after the server starts. This will be known by the servlet start and I will have to initiate the scheduler in the init().

Answer 1

My requirement is that, a java function has to run at every fixed intervals soon after the server starts

• To begin with, you can start using java.util.Timer. Here is a good link on usage of Timer class.
• Using quartz scheduler is always a better option, but Timer can be a quick way to start off with. You can find some help to start using Quartz Scheduler in Java
• Alternatively, you can also opt for ScheduledExecutorService in java. I would prefer this option over java.util.Timer

Answer 2

I suggest you to define a ServletContextListener, and to start a Quartz scheduler from its contextInitialized method.

contextInitialized is called on application deployment/reload on your application server, thus your scheduler can be initialized soon after the server starts.