The Domain class implementation in this chapter utilizes the FinancialForce.com Apex Enterprise Patterns library, which is open source and is included in the sample code of this chapter. In this library, the Apex base class, fflib_SObjectDomain, is provided to help implement the Domain layer pattern.

A basic template for a Domain class utilizing this base class is shown in the following code snippet:

public class Races extends fflib_SObjectDomain
{
  public Races(List<Race__c> races) 
  {
    super(races);
  }

  public class Constructor
    implements fflib_SObjectDomain.IConstructable
  {
    public fflib_SObjectDomain construct(List<SObject> sObjectList){
      return new Races(sObjectList);
    }
  } 
}

The first thing to note is that the constructor for this class takes a list of Race__c records, as per the guidelines described previously. The code implemented in a domain class is written with bulkification in mind. The base class constructor initializes...