Producer_Consumer_Semaphore.java

import java.util.concurrent.Semaphore;
class Producer_Consumer {
	int item;
	static Semaphore sem_Consumer = new Semaphore(0);
	static Semaphore sem_Producer = new Semaphore(1);

	void get(){
		try {
			sem_Consumer.acquire();
		}
		catch (InterruptedException e) {
			System.out.println("InterruptedException caught");
		}
		System.out.println("Item consumed by Consumer : " + item);
		sem_Producer.release();
	}

	void put(int item){
		try {
			sem_Producer.acquire();
		}
		catch (InterruptedException e) {
			System.out.println("InterruptedException caught");
		}
		this.item = item;

		System.out.println("Item produced by Producer : " + item);
		sem_Consumer.release();
	}
}

class Producer implements Runnable {
	Producer_Consumer pc;
	Producer(Producer_Consumer q){
		this.pc = q;
		new Thread(this, "Producer").start();
	}

	public void run(){
		for (int i = 0; i < 15; i++)
			pc.put(i);
	}
}

class Consumer implements Runnable {
	Producer_Consumer pc;
	Consumer(Producer_Consumer q){
		this.pc = q;
		new Thread(this, "Consumer").start();
	}

	public void run(){
		for (int i = 0; i < 15; i++)
			pc.get();
	}
}

class Producer_Consumer_2{
	public static void main(String args[]){
		Producer_Consumer pc = new Producer_Consumer();
		new Consumer(pc);
		new Producer(pc);
	}
}