Refactoring if/else logic

Question

I have a java class with a thousand line method of if/else logic like this:

if (userType == \"admin\") {
     if (age > 12) {
          if (location == \"         


        

Answer 1

Thousands? Maybe a rules engine is what you need. Drools could be a viable alternative.

Or a Command pattern that encapsulates all the "do something slightly different" logic for each case. Store each Command in a Map with the concatentation of age, location, and other factors as the key. Lookup the Command, execute it, and you're done. Nice and clean.

The Map can be stored as configuration and read in on start up. You can add new logic by adding new classes and reconfiguring.