How do I execute tasks in a thread pool

In this Q&A, we'll go over how to execute tasks in a thread pool.

With ExecutorService implementations executing tasks in multiple threads is pretty straight forward.  It involves

- creating a thread pool using Executors class

- submitting Runnable or Callable tasks for execution

- shutdown the thread pool once task execution is complete and the thread pool is no longer needed

See sample code below

ExecutorService es  = Executors.newFixedThreadPool(2); // create thread pool

// executes Runnable tasks

es.submit( () -> System.out.println(Thread.currentThread().getName()));

es.submit( () -> System.out.println(Thread.currentThread().getName()));

es.shutdown();

// waits for upto secs for threads in the pool to terminate

es.awaitTermination(1, TimeUnit.SECONDS);

System.out.println("end");