@Test
public void testGetOrDefaultExtension() {

    ExtensionLoader<InjectExt> loader = getExtensionLoader(InjectExt.class);
    InjectExt injectExt = loader.getOrDefaultExtension("non-exists");
    assertEquals(InjectExtImpl.class, injectExt.getClass());
    assertEquals(InjectExtImpl.class, loader.getOrDefaultExtension("injection").getClass());
}