Specifies that the class cannot have subclasses.

Class MyApp.Exam As %Persistent [ ClassType = persistent, Final ] {
}

The value of this keyword is boolean value.

Specifies that the class cannot have subclasses. You cannot create any additional classes that use a Final class as a super class. The Final keyword also instructs the Class Compiler that it may take advantage of certain code generation optimizations (related to the fact that instances of a final class cannot be used polymorphically).

The default value for the Final keyword is false.