ProducerConsumer.java

public class ProducerConsumer{
	static final int N = 100; //buffer size
	static producer p = new producer();
	static consumer c = new consumer();
	static monitor m = new monitor();

	public static void main(String args[]){
		p.start();
		c.start();
	}
	
	static class producer extends Thread{
		public void run(){
			int item;
			while(true){
				item = produceItem();
				m.insert(item);
			}
		}
		private int produceItem(){
			return (int)(Math.random()*100);
		}
	}

	static class consumer extends Thread{
		public void run(){
			int item;
			while(true){
				item = m.remove();
				consumeItem(item);
			}
		}
		
		private void consumeItem(int item){
			System.out.println("Item consumido: " + item);
		}
	}

	static class monitor{
		private int buffer[] = new int[N];
		private int count = 0, lo = 0, hi = 0;
		
		public synchronized void insert(int val){
			if(count == N) goToSleep();
			buffer[hi] = val;
			hi = (hi + 1) % N;
			count++;
			if (count == 1) notify();
		}

		public synchronized int remove(){
			int val;
			if (count == 0) goToSleep();	
			val = buffer[lo];
			lo = (lo+1) % N;
			count--;
			if(count == N - 1) notify();
			return val;
		}

		private void goToSleep(){
			try{
				wait();
			}catch(InterruptedException iex){}
		}
	}

}