### Question:
OSGIPluginRegistryExtension implements PluginRegistryExtension { @Override public void searchForType( PluginTypeInterface pluginType ) { tracker.registerPluginClass( pluginType.getClass() ); } OSGIPluginRegistryExtension(); static OSGIPluginRegistryExtension getInstance(); KarafBoot getKarafBoot(); synchronized void init( final PluginRegistry registry ); @Override void searchForType( PluginTypeInterface pluginType ); @Override String getPluginId( Class<? extends PluginTypeInterface> pluginType, Object pluginClass );  }### Answer:
@Test public void testSearchForType() { OSGIPluginRegistryExtension.getInstance().searchForType( OSGIPluginType.getInstance() ); verify( tracker ).registerPluginClass( OSGIPluginType.class ); }