public static <T> Collection<T> load(final Class<T> service) {
        if (SERVICES.containsKey(service)) {
            return newServiceInstances(service);
        }
        Collection<T> result = new LinkedHashSet<>();
        for (T each : ServiceLoader.load(service)) {
            result.add(each);
            cacheServiceClass(service, each);
        }
        return result;
    }
@Test
    void testLoad() {
        Collection<SpiTestInterface> actual = NacosServiceLoader.load(SpiTestInterface.class);
        assertEquals(1, actual.size());
        assertEquals(SpiTestImpl.class, actual.iterator().next().getClass());
    }