ABAP_to_the_Future

9
BRFplus
9.1.3 Rules in ABAP
Programmers know that they can make ABAP do whatever they want it to do, and
quickly at that. As you can see in Listing 9.1, it’s not too difficult to whip up some
lines of code to achieve the result demanded by the mo nster business rule
requirement.
IF ld_sanity GT 75.
CASE ld_usage.
WHEN 'BALLROOM_DANCER'.
ld_ingredients = 1.
WHEN 'MORTGAGE_SALESMAN'.
ld_ingredients = 3.
WHEN OTHERS.
ld_ingredients = 2.
ENDCASE.
ELSEIF ld_sanity LE 74 AND
ld_sanity GE 16.
CASE ld_scariness.
WHEN 'EXTRA_SCARY'.
ld_ingredients = 3.
WHEN OTHERS.
ld_ingredients = 2.
ENDCASE.
ELSE."Sanity is 15% or less
CASE ld_evilness.
WHEN 'MODERATE'.
IF ld_rages_per_day LE 1.
ld_ingredients = 2.
ELSE.
ld_ingredients = 3.
ENDIF."Rages per Day
WHEN OTHERS.
ld_ingredients = 3.
ENDCASE."Evilness
ENDIF."Sanity Percentage
ASSERT ld_ingredients NE 0.
Listing 9.1 Monster Rule in ABAP
Although this code is easy to write, the perceived problem is that the logic is hidden
away in ABAP. From the business expert’s point of view, and even from that
of the poor old business analyst, this really is a black box. However, customizing
tables and ABAP code are the traditiona l way in which business rules have been
implemented since the dawn of SAP.
364