### Question:
NetworkService extends ServiceUtil { public static Set<ClassifierInstance> getAllClassifierInstances() { HashSet<ClassifierInstance> cis = new HashSet<>(); cis.add(createDhcpIpv4ClientServer()); cis.add(createDhcpIpv4ServerClient()); cis.add(createDhcpIpv6ClientServer()); cis.add(createDhcpIpv6ServerClient()); cis.add(createDnsUdpIpv4ClientServer()); cis.add(createDnsUdpIpv4ServerClient()); cis.add(createDnsUdpIpv6ClientServer()); cis.add(createDnsUdpIpv6ServerClient()); cis.add(createDnsTcpIpv4ClientServer()); cis.add(createDnsTcpIpv4ServerClient()); cis.add(createDnsTcpIpv6ClientServer()); cis.add(createDnsTcpIpv6ServerClient()); cis.add(createSshTcpIpv4ServerClient()); cis.add(createSshTcpIpv6ServerClient()); cis.add(createSshTcpIpv4ClientServer()); cis.add(createSshTcpIpv6ClientServer()); cis.add(createIcmpIpv4()); cis.add(createIcmpIpv6()); return cis; }  static void writeDhcpClauseWithConsProvEic(TenantId tenantId, @Nullable IpPrefix ipPrefix,
            WriteTransaction writeTx); static void writeDnsClauseWithConsProvEic(TenantId tenantId, @Nullable IpPrefix ipPrefix,
            WriteTransaction writeTx); static void writeMgmtClauseWithConsProvEic(TenantId tenantId, @Nullable IpPrefix ipPrefix,
            WriteTransaction writeTx); static void writeNetworkServiceEntitiesToTenant(TenantId tenantId, WriteTransaction writeTx); static Set<ClassifierInstance> getAllClassifierInstances(); static final ContractId DHCP_CONTRACT_ID; static final Contract DHCP_CONTRACT; static final ConsumerNamedSelector DHCP_CONTRACT_CONSUMER_SELECTOR; static final ContractId DNS_CONTRACT_ID; static final Contract DNS_CONTRACT; static final ConsumerNamedSelector DNS_CONTRACT_CONSUMER_SELECTOR; static final ContractId MGMT_CONTRACT_ID; static final Contract MGMT_CONTRACT; static final ConsumerNamedSelector MGMT_CONTRACT_CONSUMER_SELECTOR; static final EndpointGroupId EPG_ID; static final EndpointGroup EPG; }### Answer:
@Test public void testGetAllClassifierInstances() { Set<ClassifierInstance> classifierInstances = NetworkService.getAllClassifierInstances(); assertNotNull(classifierInstances); assertFalse(classifierInstances.isEmpty()); assertEquals(18, classifierInstances.size()); }