Limit Number of WHEN Branches in CASE Statements

WarningMetrics & Complexity Limits#EC MAX_WHEN_COUNTRemote Enabled

Overview

Limit number of WHEN clauses per CASE.

ATC Finding Message: CASE statement has too many WHEN clauses; consider refactoring

Rationale

A CASE statement with an excessive number of WHEN branches violates the Single Responsibility Principle and often indicates missing polymorphism, dictionary tables, or strategy patterns. Complex CASE structures are prone to bugs during maintenance.

Non-Compliant

CASE lv_status.
  WHEN 'A'. ...
  WHEN 'B'. ...
  " ... 10+ more branches
ENDCASE.

Compliant

" Use a strategy pattern, lookup table, or dispatch method

Configuration & Thresholds

This check can be fine-tuned directly in the ATC Check Variant Editor (CHKV) in Eclipse ADT:

Parameter Name	Data Type	Default Value	Description & Guidance
MAX_WHEN_COUNT	Integer	10	Maximum number of WHEN clauses allowed per CASE statement (default: 10)

Suppression

To suppress findings for this rule, append the pseudo-comment to the statement:

" Standard pseudo-comment:
... "#EC MAX_WHEN_COUNT

" SAP CI_ prefix format:
... "#EC CI_MAX_WHEN_COUNT

Related Rules

• Limit Cyclomatic Complexity (McCabe Complexity Metric) — #EC MAX_CYCLO_COMP
• Limit Number of ELSEIF Branches in IF Statements — #EC MAX_ELSEIF_COUNT
• Prefer CASE over Multiple IF / ELSEIF on the Same Variable — #EC PREF_CASE

Technical Details

• Native ATC Class: ZCL_SKYLINT_MAX_WHEN_COUNT
• Implementation File: zcl_skylint_max_when_count.clas.abap