Lesson 9 Practice — Shipping Cost Utility

Create:

ZCL_SHIPPING_CALCULATOR_###
ZCL_ABAP_L09_PRACTICE_###

Constants

Define rates for at least two shipping tiers.

Static methods

Create:

CALCULATE_STANDARD
CALCULATE_EXPRESS

Both import a weight and return decfloat34.

Optional class data:

calculations_done

If used, make it externally read-only and explain why mutable class state should remain minimal.

Runner

Call methods with =>; do not instantiate the calculator.

Use at least one FINAL(...) local input.

Questions

1. Why is => used instead of ->?
2. Why is a shipping rate a good constant?
3. What is shared about CLASS-DATA?
4. What is the difference between CONSTANTS and FINAL(...)?
5. When would an instance calculator be preferable to static methods?