Yummer is a project mainly written in ..., it's free.
A yum interface in java
Yummer is a simple java interface to various yum functionalities. Currently only the search functionality is implemented
It's a toy project. I only implemented what I needed (Search multiple yum repositories for a certain package). It's not terribly hard to add more functionality such as install/remove etc but I didn't need it so it's not there. yet...