Constants and typedefs are probably the simplest constructs in IDL.
A constant is a primitive value bound to a name. A typedef is an aliasing of a type name to allow better semantic description in the IDL
definition as well as to provide a little bit of change management functionality.
The design philosophy with which Java was created specifically excludes type aliasing. Under Java, IDL typedefs mostly disappear.
You are expected to use the underlying element type rather than the alias name. A typedef declaration does not completely disappear, though.
The helper classes are still created for the type name even though a new class is not created for it. In the next lesson,
you will learn how to describe the mapping of methods in IDL interfaces in Java and how to execute remote methods.
Click the Quiz link below to take a quiz on IDL-to-Java mapping.
IDL Java Mapping - Quiz