@Override
        public void memberJoined(ClientMembershipEvent event) {
          assertFalse(fired[whichListener]);
          assertNull(member[whichListener]);
          assertNull(memberId[whichListener]);
          assertFalse(isClient[whichListener]);
          fired[whichListener] = true;
          member[whichListener] = event.getMember();
          memberId[whichListener] = event.getMemberId();
          isClient[whichListener] = event.isClient();
        }
Tests unregisterClientMembershipListener to ensure that no further events are delivered to
unregistered listeners.
geode-core/src/distributedTest/java/org/apache/geode/cache30/ClientMembershipDUnitTest.java