what are the problems of the snippet

[QkrspCmptPop]

my purpose is to implement a counting semaphore (one concurrency control object) in java. (I know it is available in java.util.concurrent, but this is the requirement).

Here is the code:

public class countingSemaphore{	
	private static final int _MOSTTABLES = 3;
	private static int availtable = _MOSTTABLES;
	private static final Object lock = new Object();	
	
	public synchronized static void Wait(){		
		while(availtable==0){		
			try{
				synchronized(lock){
					lock.wait();
				}			
			}
			catch(InterruptedException e){
				e.printStackTrace();
			}
		}
		availtable--;
	}
	
	public synchronized static void Signal(){
		while(availtable==_MOSTTABLES){
			try{
				synchronized(lock){
					lock.notifyAll();
					}				
			}
			catch(InterruptedException e){
				e.printStackTrace();
			}
		}
		availtable++;		
	}
}

The synchronized static methods lock resource sharing among instances of class. The synchronized within methods is to use wait/notifyall mechanism for a static level method.

But these codes still look strange though I do not figure out the strange reason.
Can anybody tell me why? Or any other issues I have to take care of here in order to implement the counting semaphore. Thanks.

[Fubarable]

Hello!

I'm no pro at semaphores, but I am a pro at code tags, and so I hope you don't mind that I added them to your code. Please see my signature below if you want to do this yourself in your next posts.

Good luck, and I hope you resolve this issue soon!