You can't make a complicated problem simple. But, by leveraging the right tools in your language (and the Visitor pattern) you can ensure that your code doesn't get as complicated as your problem. In ...

The Visitor design ... Visitor design pattern is a GOF (Gang of Four) pattern and can be used to define a new operation on your class sans the need of changing the existing code.

You don’t want a piece of code with a huge list of if-else statements! How do you avoid that? The Visitor pattern comes to the rescue. public class PrintVisitor implements Visitor { public void ...