### Question:
KarafCapabilityProvider extends ServiceTracker<FeaturesService, FeaturesService> implements ICapabilityProvider,
    FeaturesListener { @Override public String getId() { return KARAF; } KarafCapabilityProvider( BundleContext bundleContext ); @Override FeaturesService addingService( ServiceReference<FeaturesService> reference ); @Override String getId(); @Override Set<String> listCapabilities(); @Override ICapability getCapabilityById( String id ); @Override boolean capabilityExist( String id ); @Override Set<ICapability> getAllCapabilities(); void watchForInstall( Feature feature, SettableFuture<Boolean> future ); void watchForUnInstall( Feature feature, SettableFuture<Boolean> uninstallFuture ); @Override void featureEvent( FeatureEvent featureEvent ); @Override void repositoryEvent( RepositoryEvent repositoryEvent ); static final String KARAF; }### Answer:
@Test public void testGetId() throws Exception { karafCapabilityProvider = new KarafCapabilityProvider( bundleContext ); String id = karafCapabilityProvider.getId(); assertNotNull( id ); assert( id.equals( "Karaf" ) ); }