Java에서 인터페이스 구현의 전체 목록을 프로그래밍 방식으로 어떻게 얻을 수 있습니까?

Reflections reflections = new Reflections("firstdeveloper.examples.reflections");
Set<Class<? extends Pet>> classes = reflections.getSubTypesOf(Pet.class);

ServiceLoader<Pet> loader = ServiceLoader.load(Pet.class);
for (Pet implClass : loader) {
    System.out.println(implClass.getClass().getSimpleName()); // prints Dog, Cat
}

@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.PACKAGE)
public @interface MyPackageAnnotation {
    Class<?>[] implementationsOfPet() default {};
}

@MyPackageAnnotation(implementationsOfPet = {Dog.class, Cat.class})
package examples.reflections;

Package[] packages = Package.getPackages();
for (Package p : packages) {
    MyPackageAnnotation annotation = p.getAnnotation(MyPackageAnnotation.class);
    if (annotation != null) {
        Class<?>[] implementations = annotation.implementationsOfPet();
        for (Class<?> impl : implementations) {
            System.out.println(impl.getSimpleName());
        }
    }
}