@Override
    public void clear() {
        cache.clear();
    }
For a list of wild-carded names, return 0-* IDs for each one.
If no wildCardedFeedNames are provided, returns an empty map.

@param wildCardedFeedNames e.g. 'TEST_*' or 'TEST_FEED'
stroom-meta/stroom-meta-impl-db/src/main/java/stroom/meta/impl/db/MetaFeedDaoImpl.java