@Override
    public void increment(@Nonnull UUID txnId, boolean backup) {
        if (txnId.equals(NULL_UUID)) {
            return;
        }

        reservedCapacityCountByTxId.compute(txnId, (ignored, currentCapacityCount) -> {
            if (backup) {
                nodeWideUsedCapacityCounter.add(1L);
            } else {
                nodeWideUsedCapacityCounter.checkAndAddCapacityOrThrowException(1);
            }
            return currentCapacityCount == null ? 1L : (currentCapacityCount + 1L);
        });
    }
@Test
    public void null_uuid_does_not_increment_counter() {
        long valueBefore = nodeWideUsedCapacityCounter.currentValue();
        counter.increment(TxnReservedCapacityCounter.NULL_UUID, false);
        long valueAfter = nodeWideUsedCapacityCounter.currentValue();

        assertEquals(valueBefore, valueAfter);
    }