public final boolean isRewardHalvingPoint(final int previousHeight) {
        return ((previousHeight + 1) % REWARD_HALVING_INTERVAL) == 0;
    }
@Test
    public void isRewardHalvingPoint() {
        assertTrue(BITCOIN_PARAMS.isRewardHalvingPoint(209999));

        assertTrue(BITCOIN_PARAMS.isRewardHalvingPoint(419999));

        assertFalse(BITCOIN_PARAMS.isRewardHalvingPoint(629998));
        assertTrue(BITCOIN_PARAMS.isRewardHalvingPoint(629999));
        assertFalse(BITCOIN_PARAMS.isRewardHalvingPoint(630000));

        assertTrue(BITCOIN_PARAMS.isRewardHalvingPoint(839999));
    }