VectorQueue.java

package com.android.dvci.util;

import java.util.Vector;

public class VectorQueue implements Queue {

	Vector vector = new Vector();

	public synchronized Object dequeue() {
		if (isEmpty()) {
			throw new UnderflowException("dequeue");
		}
		Object obj = vector.elementAt(0);
		vector.removeElementAt(0);
		return obj;
	}

	public synchronized void enqueue(Object x) {
		vector.addElement(x);
	}

	public synchronized Object getFront() {
		if (isEmpty()) {
			throw new UnderflowException("getFront");
		}

		Object obj = vector.elementAt(0);
		vector.removeElementAt(0);
		return obj;
	}

	public synchronized boolean isEmpty() {
		return vector.isEmpty();
	}

	public synchronized void makeEmpty() {
		vector.removeAllElements();
	}

}