### Question:
TransportManager { ComponentName[] getRegisteredTransportComponents() { synchronized (mTransportLock) { return mRegisteredTransportsDescriptionMap .keySet() .toArray(new ComponentName[mRegisteredTransportsDescriptionMap.size()]); } } TransportManager(@UserIdInt int userId, Context context, Set<ComponentName> whitelist,
            String selectedTransport); @VisibleForTesting  TransportManager(
            @UserIdInt int userId,
            Context context,
            Set<ComponentName> whitelist,
            String selectedTransport,
            TransportClientManager transportClientManager); void setOnTransportRegisteredListener(OnTransportRegisteredListener listener); @Nullable String getCurrentTransportName(); @Nullable ComponentName getCurrentTransportComponent(); String getTransportName(ComponentName transportComponent); String getTransportDirName(ComponentName transportComponent); String getTransportDirName(String transportName); @Nullable Intent getTransportConfigurationIntent(String transportName); String getTransportCurrentDestinationString(String transportName); @Nullable Intent getTransportDataManagementIntent(String transportName); @Nullable CharSequence getTransportDataManagementLabel(String transportName); boolean isTransportRegistered(String transportName); void forEachRegisteredTransport(Consumer<String> transportConsumer); void updateTransportAttributes(
            ComponentName transportComponent,
            String name,
            @Nullable Intent configurationIntent,
            String currentDestinationString,
            @Nullable Intent dataManagementIntent,
            @Nullable CharSequence dataManagementLabel); @Nullable TransportClient getTransportClient(String transportName, String caller); TransportClient getTransportClientOrThrow(String transportName, String caller); @Nullable TransportClient getCurrentTransportClient(String caller); TransportClient getCurrentTransportClientOrThrow(String caller); void disposeOfTransportClient(TransportClient transportClient, String caller); @WorkerThread int registerAndSelectTransport(ComponentName transportComponent); @WorkerThread void registerTransports(); void dumpTransportClients(PrintWriter pw); void dumpTransportStats(PrintWriter pw); @VisibleForTesting
    static final String SERVICE_ACTION_TRANSPORT_HOST; }### Answer:
@Test public void testGetRegisteredTransportComponents() throws Exception { TransportManager transportManager = createTransportManagerWithRegisteredTransports( mTransportA1, mTransportA2, mTransportB1); ComponentName[] transportNames = transportManager.getRegisteredTransportComponents(); assertThat(transportNames) .asList() .containsExactlyElementsIn( Stream.of(mTransportA1, mTransportA2, mTransportB1) .map(TransportData::getTransportComponent) .collect(toList())); }