SimpleThreadPool.java

SimpleThreadPool.java

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

class WorkerThread implements Runnable {
    private String command;

    public WorkerThread(String s){
        this.command = s;
    }

    @Override
    public void run() {
        System.out.println(Thread.currentThread().getName()+" Start. Command = "+command);

        processCommand();

        System.out.println(Thread.currentThread().getName()+" End.");
    }

    private void processCommand() {

        try {
            Thread.sleep(1000);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }

    @Override
    public String toString(){
        return this.command;
    }
}

public class SimpleThreadPool {

    public static void main(String[] args) {
        ExecutorService executor = Executors.newFixedThreadPool(4);

        for (int i = 0; i < 100; i++) {
                Runnable worker = new WorkerThread("" + i);
                executor.execute(worker);
        }

        executor.shutdown();
        while (!executor.isTerminated()) {
        }
        System.out.println("Finished all threads");
    }
}