Filter duplicates method

[Stephen Rufle]

I have a query that I think require that I join in such a way that the 
resultset has multiple rows with the same id value.

I would like to do something similar to
org.ofbiz.entity.util.EntityUtil.filterByAnd(List<T>, Map<String, ? 
extends Object>)

but maybe called
EntityUtil.filterDuplicates(List<T> values, Map<String, ? extends 
Object> fields)

Does this type of functionality already exist in ofbiz?