I am new to static analysis of code. My application has a Cyclomatic complexity of 17,754. The application itself is only 37,672 lines of code. Is it valid to say that the complexity is high based on the lines of code? What exactly is the Cyclomatic complexity saying to me?

  What exactly is the Cyclomatic complexity saying to me?


Cyclomatic complexity is not a measure of lines of code, but the number of independent paths through a module. Your cyclomatic complexity of 17,754 means that your application has 17,754 unique paths through it. This has a few implications, typically in terms of how difficult it is to understand and test your application. For example, the cyclomatic complexity is the number of test cases needed to achieve 100% branch coverage, assuming well-written tests.

A good starting point might be the Wikipedia article on cyclomatic complexity. It has a couple of snippits of pseudocode and some graphs that show what cyclomatic complexity is all about. If you want to know more, you could also read McCabe's paper where he defined cyclomatic complexity.


  My application has a Cyclomatic complexity of 17,754 lines of code. The application itself is only 37,672 lines of code. Is it valid to say that the complexity is high based of the lines of code?


Not at all. An application with few lines of code and a high number of conditionals nested within loops could have an extremely high cyclomatic complexity. On the other hand, an application with few conditions might have a low cyclomatic complexity. That's oversimplifying it a big, but I think it gets the idea across.

Without knowing more about what your application does, it might be normal to have a higher cyclomatic complexity. I would suggest measuring cyclomatic complexity on a class or method level, however, instead of just an application level. This is a little more managable, conceptually, I think - it's easier to visualize or conceptualize the paths through a method than paths through a large application.
