public static int compareVersion(String v1, String v2) {
		StringTokenizer t1 = new StringTokenizer(v1, ".");
		StringTokenizer t2 = new StringTokenizer(v2, ".");
		while (t1.hasMoreTokens() && t2.hasMoreTokens()) {
			int n1 = Integer.parseInt(t1.nextToken());
			int n2 = Integer.parseInt(t2.nextToken());
			if (n1 != n2) return (n1 < n2) ? -1 : +1;
		}
		if (t1.hasMoreTokens()) return +1;
		if (t2.hasMoreTokens()) return -1;
		return 0;
	}