Lesson 4 Companion — Classes, Objects & Encapsulation

1. Why this version differs from older beginner OOP material

A common teaching pattern starts with public mutable attributes and fixes them later. This course starts with private state because it avoids establishing a pattern we do not want students to carry into application design.

2. FINAL class

FINAL prevents subclassing. A simple domain class can be final until inheritance is intentionally introduced later.

3. Object creation

Modern ABAP supports:

DATA(product) = NEW zcl_product_###( ... ).

Older CREATE OBJECT syntax still exists, but NEW is expression-friendly and fits modern ABAP style.

4. me->

Use it when it improves clarity, especially where an attribute and parameter share a name.

5. Reference implementation

The complete Product definition/implementation is in the Content file. A strong implementation should ensure stock never becomes negative through its public methods.

6. Encapsulation is not “getters and setters everywhere”

The stronger principle is:

private representation
+
meaningful public behavior

A setter is appropriate only when unrestricted replacement really belongs to the object's API.

SAP references

• ABAP Cloud - ABAP Development

• ABAP Keyword Documentation

• Creating ABAP Classes in ADT

• ADT Class Execution

• ABAP Objects - Objects