Understanding the Producer and Consumer Problem in Java

package producerconsumerproblem.one;

//A correct implementation of a producer and consumer problem
class Q {
    private int value;
      
    // Producer will call this method to produce a value
    public synchronized void produce(int value) throws InterruptedException {
        this.value = value;
        System.out.println("Produced: " + value);     
    }

    // Consumer will call this method to consume a value
    public synchronized int consume() throws InterruptedException {
    	System.out.println("Consumed: " + value);
        return value;
    }
}

class Producer extends Thread {
    private final Q sharedValue;

    public Producer(Q sharedValue) {
        this.sharedValue = sharedValue;
    }

    @Override
    public void run() {
        int value = 0;
        try {
            while (true) {
                sharedValue.produce(value++);
                Thread.sleep(100); // Simulate time taken to produce
            }
        } catch (InterruptedException e) {
            Thread.currentThread().interrupt();
        }
    }
}

class Consumer extends Thread {
    private final Q sharedValue;

    public Consumer(Q sharedValue) {
        this.sharedValue = sharedValue;
    }

    @Override
    public void run() {
        try {
            while (true) {
                sharedValue.consume();
                Thread.sleep(150); // Simulate time taken to consume
            }
        } catch (InterruptedException e) {
            Thread.currentThread().interrupt();
        }
    }
}

public class ProducerConsumer {
    public static void main(String[] args) {
        Q sharedValue = new Q();
        //Creating instances of Producer and Consumer
        Producer producer = new Producer(sharedValue);
        Consumer consumer = new Consumer(sharedValue);
        //Start the thread
        producer.start();
        consumer.start();
    }
}

Produced: 0
Consumed: 0
Produced: 1
Consumed: 1
Produced: 2
Consumed: 2
Produced: 3
Produced: 4
Consumed: 4
Produced: 5
Consumed: 5
Produced: 6
Produced: 7
Consumed: 7

package producerconsumerproblem.two;

//A Correct Implementation of Producer and Consumer problem
class Q {
	private int value;
	private boolean isValueAvailable = false;

	// Producer will call this method to produce a value
	public synchronized void produce(int value) throws InterruptedException {
		// Wait until the consumer consumes the current value
		while (isValueAvailable) {
			wait();
		}
		this.value = value;
		System.out.println("Produced: " + value);
		isValueAvailable = true;
		// Notify the consumer thread that a value has been produced
		notify();
	}

	// Consumer will call this method to consume a value
	public synchronized int consume() throws InterruptedException {
		// Wait until the producer provides a new value
		while (!isValueAvailable) {
			wait();
		}
		System.out.println("Consumed: " + value);
		isValueAvailable = false;
		// Notify the producer thread that the value has been consumed
		notify();
		return value;
	}
}

class Producer extends Thread {
	private final Q sharedValue;

	public Producer(Q sharedValue) {
		this.sharedValue = sharedValue;
	}

	@Override
	public void run() {
		int value = 0;
		try {
			while (true) {
				sharedValue.produce(value++);
				Thread.sleep(100); // Simulate time taken to produce
			}
		} catch (InterruptedException e) {
			Thread.currentThread().interrupt();
		}
	}
}

class Consumer extends Thread {
	private final Q sharedValue;

	public Consumer(Q sharedValue) {
		this.sharedValue = sharedValue;
	}

	@Override
	public void run() {
		try {
			while (true) {
				sharedValue.consume();
				Thread.sleep(150); // Simulate time taken to consume
			}
		} catch (InterruptedException e) {
			Thread.currentThread().interrupt();
		}
	}
}

public class ProducerConsumer {
	public static void main(String[] args) {
		Q sharedValue = new Q();
		
		Producer producer = new Producer(sharedValue);
		Consumer consumer = new Consumer(sharedValue);
		//Starting both the thread
		producer.start();
		consumer.start();
	}
}

Produced: 0
Consumed: 0
Produced: 1
Consumed: 1
Produced: 2
Consumed: 2
Produced: 3
Consumed: 3
Produced: 4
Consumed: 4
Produced: 5
Consumed: 5
Produced: 6
Consumed: 6