### Question:
HazelcastClient extends SafeLifecycle implements TopologyService { @Override public CoreTopology localCoreServers() { return localCoreTopology; } HazelcastClient( HazelcastConnector connector, JobScheduler scheduler, LogProvider logProvider,
            Config config, MemberId myself ); @Override Map<MemberId,RoleInfo> allCoreRoles(); @Override MemberId myself(); @Override String localDBName(); @Override CoreTopology allCoreServers(); @Override CoreTopology localCoreServers(); @Override ReadReplicaTopology allReadReplicas(); @Override ReadReplicaTopology localReadReplicas(); @Override Optional<AdvertisedSocketAddress> findCatchupAddress( MemberId memberId ); @Override void init0(); @Override void start0(); @Override void stop0(); @Override void shutdown0();  }### Answer:
@Test public void shouldReturnTopologyUsingHazelcastMembers() throws Throwable { Set<Member> members = asSet( makeMember( 1 ), makeMember( 2 ) ); HazelcastClient client = startedClientWithMembers( members, config() ); CoreTopology topology = client.localCoreServers(); assertEquals( members.size(), topology.members().size() ); }