FixThreadPool.java

import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

public class ThreadPool {
    
    private static class DoSomething implements Runnable {

        private int taskId;

        public DoSomething(int taskId) {
            this.taskId = taskId;
        }

        @Override
        public void run() {
            System.out.println("Currently running task " + taskId + " by " + Thread.currentThread().getName());
        }
    }

    public static void main(String[] args) {
        ExecutorService service = Executors.newFixedThreadPool(10); // creating a fixed size thread pool
        for (int i = 1; i <= 100; i++) {
            service.submit(new DoSomething(i));
        }
        service.shutdown();
    }
}