Force.com Enterprise Architecture - Second Edition

Extending the application logic with Apex interfaces

An Apex Interface can be used to describe a point in your application logic where custom code written by Developer X can be called. For example, in order to provide an alternative means to calculate championship points driven by Developer X, we might expose a global interface describing an application callout that looks like this:

global class ContestantService {global interface IAwardChampionshipPoints {
    void calculate(List<Contestant__c> contestants);
  }
}

By querying Custom Metadata records from the Callouts custom metadata type, which has been included in the source code for this chapter, code in the application can determine whether Developer X has provided an implementation of this interface ...