DefaultPlatform extends Platform { @Override protected long getCurrentTimeNanosImpl() { return clock.getCurrentTimeNanos(); } DefaultPlatform();   DefaultPlatform(
      BackendFactory factory, LoggingContext context, Clock clock, LogCallerFinder callerFinder);   }
@Test public void testClock() { Mockito.when(mockClock.getCurrentTimeNanos()).thenReturn(123456789000L); assertThat(platform.getCurrentTimeNanosImpl()).isEqualTo(123456789000L); }