### Question:
VerboseTracerFactory extends DefaultTracerFactory { @Override public PageCacheTracer createPageCacheTracer( Monitors monitors, JobScheduler jobScheduler, SystemNanoClock clock, Log msgLog ) { return new VerbosePageCacheTracer( msgLog, clock ); }  @Override String getImplementationName(); @Override PageCacheTracer createPageCacheTracer( Monitors monitors, JobScheduler jobScheduler, SystemNanoClock clock,
            Log msgLog );  }### Answer:
@Test public void verboseFactoryCreateVerboseTracer() { BufferingLog msgLog = new BufferingLog(); PageCacheTracer pageCacheTracer = tracerFactory().createPageCacheTracer( new Monitors(), new OnDemandJobScheduler(), Clocks.nanoClock(), msgLog ); pageCacheTracer.beginCacheFlush(); assertEquals( "Start whole page cache flush.", msgLog.toString().trim() ); }