class MacAddress {

	public static MacAddress broadcast() {
		if (broadcast == null) {
			byte[] pole = new byte[6];
			for (int i = 0; i < 6; i++) {
				pole[i] = (byte) 255;
			}
			broadcast = new MacAddress(pole);
		}
		return broadcast;
	}

}

class MacAddressTest {

     @Test
     public void testBroadcast() {

         MacAddress mac;
         String sm;

         sm="ff:ff:ff:ff:ff:ff";
         mac = new MacAddress(sm);
         assertTrue(MacAddress.isBroadcast(mac));

         sm="1a:4c:05:49:ad:f9";
         mac = new MacAddress(sm);
         assertFalse(MacAddress.isBroadcast(mac));
     }

}