@SuppressWarnings("unchecked")
    protected Map<K, V> transform(Map<K, Group> groups) {
        return (Map<K,V>) groups;
    }
Provides aggregated results as a map

@author tiwe

@param <K>
@param <V>
querydsl-core/src/main/java/com/querydsl/core/group/GroupByMap.java