abstract class HS.FHIR.DTL.Util.API.ExecDefinition
No other package names are acceptable at the start of the className.
Regardless of which name prefix enters the method in the className, this method first looks in the custom DTL package (if there is one configured) and if the corresponding DTL class is not found in the custom package, the method looks in the standard package.
The method returns the full package and class name of the first class it finds. If neither DTL class is found, or if the name prefix is unacceptable, it returns an empty string.
When packageName is empty, transformation code ignores all custom DTLs and always uses the standard DTLs.
Otherwise, at runtime, before executing any DTL class, the transformation code looks to see if a class by that name exists in the custom DTL package. If so, it executes the custom DTL class. If not, the transformation code executes the corresponding standard DTL class.
Essentially, the custom package name is intended to replace the standard package name when looking for a customized version of a given DTL class. For example, if the standard package name is "HS.FHIR.DTL", and the custom package name is "HS.Local.FHIR.DTL", then at run-time if the specified standard class is HS.FHIR.DTL.SDA3.vSTU3.Patient.Patient, the framework will first look for HS.Local.FHIR.DTL.SDA3.vSTU3.Patient.Patient.
The packageName value may not be the same as the standard DTL package name for the product, may not be a sub-package of the standard package, and may not occupy a reserved product package - the exception being HS.Local which is within HS.