### Question:
AbstractClientTracer extends AbstractTracer { @Override protected String getServerDigestReporterRollingKey() { return null; } AbstractClientTracer(String tracerType);   }### Answer:
@Test public void getServerDigestReporterRollingKey() { String serverDigestReporterRollingKey = clientTracer.getServerDigestReporterRollingKey(); Assert.assertTrue(serverDigestReporterRollingKey == null); }