What is the use of a Thread pool in Java?

Question

What is the use of a Thread pool? Is there a good real world example?

Answer 1

You may assume Threads to be actual workers and Thread Pools to be group of workers. You may create multiple groups for various reasons like priority, purpose, etc. So, while one pool may be for general purpose tasks like background schedules, email broadcasting, etc. there might be a transaction processing pool to simultaneously process multiple transactions. In case of an Executor Service, I am sure you would not like to delay the transactional jobs to be completed after other non-critical activities like broadcasting confirmation emails or database maintenance activities are not completed. You may segregate them into pools and maintain them independently. That's a very simplistic answer without getting into technical jargons. Regards, KT