/**
 * Semaphore.java
 *
 * A basic counting semaphore using Java synchronization.
 *
 */

public final class Semaphore
{
   private int count;

   public Semaphore() {
      count = 0;
   }

   public Semaphore(int value) {
      count = value;
   }

   public synchronized void P() {
      while (count <= 0) {
         System.out.println("Thread " + Thread.currentThread().getName() +" waits in P-Operation!");
         try { wait();
         } catch (InterruptedException e) {
				  Thread.currentThread().interrupt();
				  break;
		   }
      }
      count--;
   }

   public synchronized void V() {
      ++count;

      notify();
   }

	public int getCounter() {
		return count;
	}
}