MultiThreading 2 : wait() & notify()

import java.util.*;


class Q {
    int num;
    boolean valueSet = false;
    public  synchronized void set(int num){

        // wait for get to retrieve  before setting value again ..
        while(valueSet){
            try { wait(); } catch (Exception e){}
        }
        valueSet = true;
        this.num = num;
        System.out.println("set " +this.num);
        notify();
    }
    public synchronized void get(){

        // wait for set to put value before getting it
        while(valueSet == false){
            try { wait(); } catch (Exception e){}
        }
        System.out.println("get " +this.num);
        valueSet = false;
        notify();
    }
}

class Producer implements Runnable{
    Q q;

    public Producer(Q q){
        this.q = q;
        Thread t = new Thread(this, "Producer");
        t.start();
    }

    public void run(){
        int i=0;
        while(true){
            q.set(i++);
            try{
                Thread.sleep(100);
            }catch(Exception e){

            }
        }
    }
}

class Consumer implements Runnable{
    Q q;

    Consumer(Q q){
        this.q =q;
        Thread t = new Thread(this, "Consumer");
        t.start();
    }

    public void run(){
        while(true){
            q.get();
            try{
                Thread.sleep(1000);
            }catch(Exception e){

            }
        }
    }

}

public class Main{
    public static void main(String args[]) throws Exception{
        Q q = new Q();
        new Producer(q);
        new Consumer(q);
        /*  here producer can produce faster than consumer can consume so
            we make producer wait till consumer sets flag to false ..
            and vice versa
        */
    }
}