What Is Cyclomatic Complexity?

What Is Cyclomatic Complexity?

Cyclomatic complexity in CodeScan is calculated by the number of decision points in a method (like if, while, for, and case statements), plus one for the method entry. A higher cyclomatic complexity indicates more decision points, making the code harder to read, maintain, and test.

Complexity Levels:

• 1-4 (Low Complexity): Simple methods, easy to understand and maintain.

• 5-7 (Moderate Complexity): Acceptable but should be monitored.

• 8-10 (High Complexity): Consider refactoring to simplify.

• 11+ (Very High Complexity): Strongly recommended to refactor.

Significance of Report Level (default 10):

The report-level parameter in tools that analyze cyclomatic complexity flags methods with a complexity of 10 or higher for further inspection. This helps identify methods that might need refactoring due to their complexity.

How Is Cyclomatic Complexity Calculated?

For example, the method below would have a cyclomatic complexity of 5.

public void newMethod() {
     for(Integer i = 0; i < 100; i++){
      if (a == b && b == c){
        doStuff();
      } else if(a != b) {
        doOtherStuff();
      }
     }
   }

This counts:

• The entry to the method

• The entry to the for loop

• The if statement and the first conditional

• The second conditional in the if statement

• The elseif statement

This does not include:

• else statements

• when else in switch statements

The cyclomatic complexity for a class will be the average complexity between all methods in that class.

How Do I Reduce Cyclomatic Complexity?

• Break Down Methods: Split complex methods into smaller, more focused functions.

• Use Helper Methods: Extract repetitive logic into separate methods.

• Simplify Conditionals: Refactor nested if statements into simpler, sequential checks.

• Use Switch Statements: For multiple conditions, switch statements can streamline the logic.

Following these guidelines will help you write cleaner, more maintainable, and less error-prone Apex code.