Producer Consumer Problem

Main.java

import java.io.*;
import java.lang.*;

class Factory
{
	private int contents;
	private boolean available = false;
	
	public synchronized int get()
	{
		while(!available)
		{
			try
			{
				wait();
			}
			catch(InterruptedException e)
			{
				e.printStackTrace();
			}
		}
		available = false;
		notify();
		return contents;
	}
	
	public synchronized void put(int contents)
	{
		while(available)
		{
			try
			{
				wait();
			}
			catch(InterruptedException e)
			{
				e.printStackTrace();
			}
		}
		available = true;
		this.contents = contents;
		notify();
	}
}

class Producer extends Thread
{
	private Factory factory;
	Producer(Factory factory)
	{
		this.factory = factory;
	}
	public void run()
	{
		int randval;
		for(int i = 0; i < 10; i ++)
		{
			randval = (int)(1+Math.random()*100);
			factory.put(randval);
			System.out.println("Producer put " + randval);
			try
			{
				sleep( (int)(1+Math.random()*5)*100 ); //Just wait for random time after producing
			}
			catch(InterruptedException e)
			{
				e.printStackTrace();
			}
		}
	}
}

class Consumer extends Thread
{
	private Factory factory;
	Consumer(Factory factory)
	{
		this.factory = factory;
	}
	public void run()
	{
		int val;
		for(int i = 0; i < 10; i++)
		{
			val = factory.get();
			System.out.println("Consumer got " + val);
		}
	}
}

public class Main
{
	public static void main(String[] args)
	{
		Factory f1 = new Factory();
		Producer p1 = new Producer(f1);
		Consumer c1 = new Consumer(f1);
		p1.start();
		c1.start();
	}
}