@Override
    public K fetchFirst() {
        try {
            DBCursor c = createCursor().limit(1);
            if (c.hasNext()) {
                return transformer.apply(c.next());
            } else {
                return null;
            }
        } catch (NoResults ex) {
            return null;
        }
    }
Fetch first with the specific fields

@param paths fields to return
@return first result
querydsl-mongodb/src/main/java/com/querydsl/mongodb/AbstractMongodbQuery.java