### Question:
KafkaAdminClient extends AdminClient { static String generateClientId(AdminClientConfig config) { String clientId = config.getString(AdminClientConfig.CLIENT_ID_CONFIG); if (!clientId.isEmpty()) return clientId; return "adminclient-" + ADMIN_CLIENT_ID_SEQUENCE.getAndIncrement(); } private  KafkaAdminClient(AdminClientConfig config, String clientId, Time time, Metadata metadata,
                     Metrics metrics, KafkaClient client, TimeoutProcessorFactory timeoutProcessorFactory); @Override void close(long duration, TimeUnit unit); @Override CreateTopicsResult createTopics(final Collection<NewTopic> newTopics,
                                           final CreateTopicsOptions options); @Override DeleteTopicsResult deleteTopics(final Collection<String> topicNames,
                                           DeleteTopicsOptions options); @Override ListTopicsResult listTopics(final ListTopicsOptions options); @Override DescribeTopicsResult describeTopics(final Collection<String> topicNames, DescribeTopicsOptions options); @Override DescribeClusterResult describeCluster(DescribeClusterOptions options); @Override DescribeAclsResult describeAcls(final AclBindingFilter filter, DescribeAclsOptions options); @Override CreateAclsResult createAcls(Collection<AclBinding> acls, CreateAclsOptions options); @Override DeleteAclsResult deleteAcls(Collection<AclBindingFilter> filters, DeleteAclsOptions options); @Override DescribeConfigsResult describeConfigs(Collection<ConfigResource> configResources, final DescribeConfigsOptions options); @Override AlterConfigsResult alterConfigs(Map<ConfigResource, Config> configs, final AlterConfigsOptions options);  }### Answer:
@Test public void testGenerateClientId() { Set<String> ids = new HashSet<>(); for (int i = 0; i < 10; i++) { String id = KafkaAdminClient.generateClientId(newConfMap(AdminClientConfig.CLIENT_ID_CONFIG, "")); assertTrue("Got duplicate id " + id, !ids.contains(id)); ids.add(id); } assertEquals("myCustomId", KafkaAdminClient.generateClientId(newConfMap(AdminClientConfig.CLIENT_ID_CONFIG, "myCustomId"))); }