### Question:
AckDelay { public long delay(final long delay) { return Math.max(ticker.nanoTime() - delay, 0); } AckDelay(final int ackDelayExponent, final Ticker ticker); long calculate(final long delay, final TimeUnit unit); long time(); long delay(final long delay);  }### Answer:
@Test public void delay() { assertEquals(23, ackDelay.delay(100)); }
@Test public void delayNegative() { assertEquals(0, ackDelay.delay(200)); }