protected String getRewriteFromFSA(Query query,
                                       String dictName,
                                       String key) throws RuntimeException {
        return RewriterUtils.getRewriteFromFSA(query, rewriterDicts, dictName, key);
    }
Retrieve rewrite from FSA given the original query

@param query Query object from searcher
@param dictName FSA dictionary name
@param key The original query used to retrieve rewrite
           from the dictionary
@return String The retrieved rewrites, null if query
        doesn't exist
container-search/src/main/java/com/yahoo/search/query/rewrite/QueryRewriteSearcher.java