### Question:
StepClock implements Clock { @Override public long monotonicTime() { return impl.monotonicTime(); } StepClock(Clock impl, long step); @Override long wallTime(); @Override long monotonicTime();  }### Answer:
@Test public void monotonicTime() { ManualClock mc = new ManualClock(); StepClock sc = new StepClock(mc, 10000); mc.setMonotonicTime(5000); Assertions.assertEquals(5000L, sc.monotonicTime()); mc.setMonotonicTime(10000); Assertions.assertEquals(10000L, sc.monotonicTime()); mc.setMonotonicTime(20212); Assertions.assertEquals(20212L, sc.monotonicTime()); }