private TaggableItem firstWord(CompositeItem composite) {
        // yes, this assumes only WordItem instances in the CompositeItem
        int l = composite.getItemCount();
        if (l == 0) {
            return null;
        } else {
            return (TaggableItem) composite.getItem(0);
        }
    }
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