private CompositeItem chooseComposite(BlockItem current, CompositeItem parent, String indexName) {
        if (parent instanceof PhraseItem || current instanceof PhraseSegmentItem)
            return createPhraseSegment(current, indexName);
        else
            return createAndSegment(current);

    }
Replaces query terms with their stems

@author Mathias Lidal
@author bratseth
@author Steinar Knutsen
container-search/src/main/java/com/yahoo/prelude/querytransform/StemmingSearcher.java