COBOL Tutorial

SUPER - Call Parent Method

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Overview

Use SUPER inside an overridden method to invoke the parent implementation, then add/alter behavior.

🧱 Analogy

Building an extension on a house: you rely on the existing foundation (SUPER) and add rooms.

Override and Call SUPER

cobol

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CLASS-ID. BASE.
METHOD-ID. CALC TOTAL PUBLIC.
PROCEDURE DIVISION USING AMT RETURNING RES.
    MOVE AMT TO RES
    EXIT METHOD.
END METHOD CALC.
END CLASS BASE.
 
CLASS-ID. DERIVED INHERITS FROM BASE.
METHOD-ID. CALC OVERRIDE.
PROCEDURE DIVISION USING AMT RETURNING RES.
    INVOKE SUPER "CALC" USING AMT RETURNING RES
    ADD 10 TO RES
    EXIT METHOD.
END METHOD CALC.

Signature must match; call SUPER first, then customize.

Best Practices and Pitfalls

Best Practices

Document whether SUPER must be called (before/after)
Keep overrides minimal and focused

Common Mistakes

Mistake	Problem	Fix
Not calling SUPER when required	Violates base class contract	Call SUPER or re-implement contract
Changing signature	Not an override	Match parent signature

Quick Reference

Action	Syntax	Example
Call parent	INVOKE SUPER "name"	INVOKE SUPER "INIT"
Override	METHOD-ID. name OVERRIDE	METHOD-ID. CALC OVERRIDE

Test Your Knowledge

1. What does SUPER refer to?

Current object
Parent class implementation
Sibling object
Factory

2. How to call the parent method?

INVOKE SELF
INVOKE SUPER
CALL PARENT
DISPLAY SUPER

3. When to use SUPER?

Always
When you need base behavior plus extra logic
Never
Only in main program

Frequently Asked Questions

Related Concepts

OVERRIDE

Method overriding in OO COBOL.

OBJECT-REFERENCE

Referencing objects.

STANDARD-DECIMAL SWITCH