private Filter getFilter() {
        if (filter == null && !filters.isEmpty()) {
            filter = new ChainedFilter(filters.toArray(new Filter[0]));
        }
        return filter;
    }
Apply the given Lucene filter to the search results

@param filter filter
@return the current object
querydsl-lucene3/src/main/java/com/querydsl/lucene3/AbstractLuceneQuery.java