The problem with our current project is that we're using Spring MVC but we only use hashmap for binding (is binding is a correct term for this?) of data with our mapper (We use Mybatis, and also when we get this source code they already implements this kind of stuff, mvc with no models hahaha) for the sake the code to be consistent.

Maybe after I read the documentation of Mybatis and learn how to implements joins, I'll ask a permission to change the hashmap with actual models.