Java Clean Code Tutorial #13 – Hero & God Methods!

Ever needed to change a method or class that is like 10,000 lines long?

Unfortunately the majority of codebases have a few classes that grown to contain methods that are simply hundreds or thousands of lines long. Usually there are no tests or low quality tests to go with it!

This can happen for many reasons:

Developers may be unaware of good software design (SRP SOLID)
No code reviews
Programmers simply don't really care about the product / software
I'll tidy it up later mentality
5 lines more logic wont hurt mentality
Cheap outsourcing of development by contractors without good software design
Disgruntled developers

If you need to add some logic into a method that is already 1000 lines long I recommend you:

Create a new class to contain the new logic
Write all associated unit tests for the new class's logic
Add a method call to the new class from the 1000 line long method.

Extracting any new logic into a new class & method and making a reference from the god method will:

Enable your application to have at least some tests for the new functionality
Start to introduce good design patterns into the code base
Chances are if another developer sees this pattern they will follow the same in the future
If you need to further change that functionality you have a unit test suite already made! This means you can make changes with confidence.
Overall easier for you to understand the codebase

Till next time!

Cheers!
Philip

Sorry about the wind at the start! I now have a deadcat.... :)