Question

I just saw someone post the following, in a rant on ugly code:

public static 
    Tuple<ArrayList<ArrayList<ArrayList<String>>>, 
          ArrayList<ArrayList<ArrayList<String>>>>     
    split(
          ArrayList<ArrayList<ArrayList<String>>> data, [..]);

(layout by me, in a laughable attempt to get this semi-readable)

I’ve been looking for a way to make this look a bit like this (non-functional) code:

TypeParam T = ArrayList<ArrayList<ArrayList<String>>>;
public static Tuple<T,T> split( T data, [..]);

So far the best solution I’ve found is to define a class (in this ex. a class Data), which extends ArrayList<ArrayList<ArrayList<String>>>, which would make the code look like this:

public static Tuple<Data, Data> split( Data data, [..]);

While this method is quite satisfactory, I don’t want to give up on the possibility that there is some way of using generics that I’m missing, and I’m wondering if Java has a way of doing this in an even more aesthetically pleasing way.

Another solution I’m playing with is using an Annotation Processor to fix this for me, however I feel this misses a certain amount of simplicity.

Answer 1

How about

 public static <T extends ArrayList<ArrayList<String>>> Tuple<T,T> 
      split(T data);

But I agree with @esej that you probably want some class to encapsulate the list-of-lists-of-lists-of-strings data structure.

I am also not sure if you should have ArrayList hard-coded in there (as opposed to using the interface List).