@Test
  public void receivedPingNewClientRegistersWithCurrentTimeAndIncrementsStat() {
    ClientProxyMembershipID mockId = mock(ClientProxyMembershipID.class);
    clientHealthMonitor.registerClient(mockId);
    clientHealthMonitor.receivedPing(mockId);
    assertThat(clientHealthMonitor.getClientHeartbeats().get(mockId)).isNotNull()
        .isLessThanOrEqualTo(System.currentTimeMillis());
    verify(mockStats).incClientRegisterRequests();
  }
This is a functional-test for <code>ClientHealthMonitor</code>.
geode-core/src/test/java/org/apache/geode/internal/cache/tier/sockets/ClientHealthMonitorTest.java