### Question:
ResolverUtil { public ResolverUtil<T> find(Test test, String packageName) { String path = getPackagePath(packageName); try { List<String> children = VFS.getInstance().list(path); for (String child : children) { if (child.endsWith(".class")) { addIfMatching(test, child); } } } catch (IOException ioe) { log.error("Could not read package: " + packageName, ioe); } return this; }  Set<Class<? extends T>> getClasses(); ClassLoader getClassLoader(); void setClassLoader(ClassLoader classloader); ResolverUtil<T> findImplementations(Class<?> parent, String... packageNames); ResolverUtil<T> findAnnotated(Class<? extends Annotation> annotation, String... packageNames); ResolverUtil<T> find(Test test, String packageName);  }### Answer:
@Test void find() { ResolverUtil<VFS> resolverUtil = new ResolverUtil<>(); resolverUtil.find(new ResolverUtil.IsA(VFS.class), "org.apache.ibatis.io"); Set<Class<? extends VFS>> classSets = resolverUtil.getClasses(); assertEquals(classSets.size(), 3); classSets.forEach(c -> assertTrue(VFS.class.isAssignableFrom(c))); }