DLM Evaluators allow portal administrators to distribute DLM fragments to uPortal users. Evaluators distributed with uPortal allow administrators to distribute fragments based on user attributes, group memberships, and authentication status.
To create a new DLM evaluator, you must write a new implementation of org.jasig.portal.layout.dlm.Evaluator. This simple API will allow you to indicate whether a particular fragment should appear for a given user.