ThreadPool.java

import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.ArrayBlockingQueue;
import java.util.concurrent.BlockingQueue;

public class ThreadPool implements IThreadPool {
    private List<PoolThread> threads;
    private BlockingQueue<ITask> tasks;
    private boolean isStopped = false;

    public ThreadPool(int numberOfThreads, int maxNumberOfTasks) {
        threads = new ArrayList<>();
        tasks = new ArrayBlockingQueue<>(maxNumberOfTasks);
        this.fillThreads(numberOfThreads);
        this.start();
    }

    @Override
    public synchronized void schedule(ITask task) {
        if (this.isStopped) {
            throw new IllegalArgumentException("Cannot accept any more tasks!");
        }
        try {
            this.tasks.put(task);
        } catch (InterruptedException e) {
            // well someone interrupted the process..
        }
    }

    @Override
    public synchronized void stop() {
        this.isStopped = true;
        for (PoolThread thread : this.threads) {
            thread.stopThread();
        }
    }

    private void start() {
        for (Thread thread : this.threads) {
            thread.start();
        }
    }

    private void fillThreads(int numberOfThreads) {
        for (int i = 0; i < numberOfThreads; i++) {
            this.threads.add(new PoolThread(this.tasks));
        }
    }
}