/**
 * Barrier used to put a thread to sleep until an action has happened a 
 * given number of times.
 * 
 * @author Michael Parker
 */
public class CountingBarrier {
	protected int count;
	protected int release;
	
	public CountingBarrier() {
		this(0);
	}
	
	public CountingBarrier(int new_release) {
		set(new_release);
	}
	
	public synchronized void set(int new_release) {
		count = 0;
		release = new_release;
	}
	
	public synchronized void await() {
		while (count < release) {
			try {
				wait();
			}
			catch (InterruptedException e) {
				// interrupted, so just return
				return;
			}
		}
	}
	
	public synchronized void touch() {
		if (count >= release) {
			return;
		}
		else if (++count == release) {
			notifyAll();
		}
	}
	
	public synchronized String toString() {
		StringBuffer sbuf = new StringBuffer(1024);
		sbuf.append("count = ").append(count);
		sbuf.append(", release = ").append(release);
		return sbuf.toString();
	}
}