private static String prefixLabel(int scale) {
        switch (scale) {
        case COIN_SCALE:      return "Coin-";
        case 1:               return "Decicoin-";
        case 2:               return "Centicoin-";
        case MILLICOIN_SCALE: return "Millicoin-";
        case MICROCOIN_SCALE: return "Microcoin-";
        case -1:              return "Dekacoin-";
        case -2:              return "Hectocoin-";
        case -3:              return "Kilocoin-";
        case -6:              return "Megacoin-";
        default: return "Fixed (" + String.valueOf(scale) + ") ";
        }
    }
@Test
    public void testPrefixLabel() {
        assertEquals(String.format("%s%s %s", expectedOutput, "format", btcFixedFormat.pattern()),
                btcFixedFormat.toString());
    }