Producer-Consumer Problem

import java.util.Random;
import java .util.*;
import java.util.concurrent.Semaphore;
class QUsingSemaphore{
   private boolean isProduced = false;
   private final Semaphore bsemaphore = new Semaphore(1);
   private static int n;
   public synchronized boolean isProduced(){
      return isProduced;
   }
   public synchronized void setProduced(boolean isProduced){
      this.isProduced = isProduced;
   }
   public void produce(int n, int id){
      try{
         if((!isProduced() || this.n!=10) && n > 0){
            bsemaphore.acquire();
            setN(n);
            System.out.println("Produced : "+1+" Item by P"+id+"\nStock="+n+"\n");
            setProduced(true);
         }
      }
      catch(InterruptedException ie){
         ie.printStackTrace();
      }
      finally{
         bsemaphore.release();
      }
      try{
         Thread.sleep(new Random().nextInt(5)*1000);
      }
      catch(InterruptedException ie){
         ie.printStackTrace();
      }
   }
   public void consume(int id){
      try{
            if(isProduced()){
               bsemaphore.acquire();
               int temp=resetN();
               System.out.println("Consumed : "+1+" Item by C"+id+"\nStock="+temp+"\n");
               if(temp==0)
                  setProduced(false);
            }
      }
      catch(InterruptedException ie){
         ie.printStackTrace();
      }
      finally{
         bsemaphore.release();
      }
      try{
         Thread.sleep(new Random().nextInt(5)*1000);
      }
      catch(InterruptedException ie){
         ie.printStackTrace();
      }
   }
   public synchronized int resetN(){
      this.n--;
      return this.n;
   }
   public synchronized int getN(){
      return n;
   }
   public synchronized void setN(int n){
      this.n= n;
   }
}
class Consumer implements Runnable{
   private final QUsingSemaphore q;
   int id;
   public Consumer(QUsingSemaphore q, int id){
      this.q=q;
      this.id=id;
   }
   public void run(){
      while(true)
         q.consume(id);
   }
}
class Producer implements Runnable{
   private final QUsingSemaphore q;
   int id;
   static int count=0;
   public Producer(QUsingSemaphore q, int id){
      this.q=q;
      this.id=id;
   }
   public void run(){
      while(count++ < 20){
         int j = q.getN();
         q.produce(++j, id);
         System.out.println("Total items  produced: "+count+"\n");
      }
      System.out.println("20 items produced. Now exiting.");
      System.exit(0);
   }
}
class ProducerConsumerTest{
   public static void main(String args[]){
      //Scanner sc=new Scanner(System.in);
      //System.out.println("enter the no. of producers and consumers one by one");
      int np=2, nc=2, i, j;
      QUsingSemaphore q = new QUsingSemaphore();
      for(i=1; i<=np; i++) new Thread(new Producer(q, i)).start();;
      for (i=1; i<=nc; i++ ) new Thread(new Consumer(q,i)).start();;
   }
}