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July 18, 2005: On the missing super keyword in PL/SQL

Suppose, I have a type (named base_type) defined as follows: 
create type base_type as object (
  dummy  number,  -- prevent PLS-00589: no attributes found in object type "BASE_TYPE"
  member procedure proc_1
) not final not instantiable;
/

create type body base_type as

  member procedure proc_1 is begin
    dbms_output.put_line('base_type: proc_1');
  end proc_1;

end;
/
Then, I derive a new type from base_type (named deriv_type): 
create type deriv_type under base_type (
  overriding member procedure proc_1,
             member procedure proc_2
);
/

create type body deriv_type as

  overriding member procedure proc_1 is begin
    dbms_output.put_line('deriv_type: proc_1');
  end proc_1;

  member procedure proc_2 is begin
    self.proc_1;
    --super.proc_1;
  end proc_2;
  
end;
/
Now, I want to call base_type's proc_1 from deriv_type's proc_2. Every Java programmer would assume that there is a super keyword to do that: 
super.proc_1;
However, that's not the case. The key phrase in the manual is: When implementing methods using PL/SQL, you cannot call a base or supertype object method with the super keyword or an equivalent method in a derived object. See Oracle Database Application Developer's Guide - Object-Relational Features for additional information on supertypes, subtypes, and object methods..
Ok. I understand.

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