A method that can be useful to debug large inheritance trees is the 'Class' method. Only if this method is not found Object REXX will raise an error. This behaviour allows the object itself to capture such an error condition, issue a warning to the user of the program, and continue the program. This mechanism can also be used to capture messages for an object that are implemented in a common external function expecting the message name as an argument. Often you need methods that are solely used to give access to an instance variable from the outside of an object.
Attribute methods give access to instance variables of the same name.
If you want to maintain properties that are valid for a whole class you can use 'class methods'. Class methods are not executed for a specific object of the class but for the whole class, thus the message has to be sent to the class object. They can be useful to define class specific constants or to maintain class specific default values. Now sorting using Descending sort order. Now sorting using Descending sort order.