### Question:
CompositeRegistry implements Registry { @Override public Clock clock() { return clock; } CompositeRegistry(Clock clock); void add(Registry registry); void remove(Registry registry); void removeAll(); @Override Clock clock(); @Override Id createId(String name); @Override Id createId(String name, Iterable<Tag> tags); @Override void register(Meter meter); @Override ConcurrentMap<Id, Object> state(); @Override Counter counter(Id id); @Override DistributionSummary distributionSummary(Id id); @Override Timer timer(Id id); @Override Gauge gauge(Id id); @Override Gauge maxGauge(Id id); @Override Meter get(Id id); @Override Iterator<Meter> iterator();  }### Answer:
@Test public void testInit() { CompositeRegistry registry = new CompositeRegistry(clock); Assertions.assertSame(clock, registry.clock()); }