@Override
    protected void doDelete(final List<MetaData> dataList) {
        dataList.forEach(metaData -> metaDataSubscribers.forEach(metaDataSubscriber -> metaDataSubscriber.unSubscribe(metaData)));
    }
@Test
    public void testDoDelete() {
        List<MetaData> metaDataList = createFakeMetaDataObjects(3);
        metaDataHandler.doDelete(metaDataList);
        metaDataList.forEach(metaData ->
                subscribers.forEach(subscriber -> verify(subscriber).unSubscribe(metaData)));
    }