What's the harm in using Anonymous class?

Question

The question arose while reading a answer to this question - How do I join two lists in java. This answer gave the solution

List newList = new Arra         


        

Answer 1

It's not a bad approach per se, say, in performance or anything like that, but the approach is a bit obscure and when using something like this, you always (say, 99%) have to explain this approach. I think that's one of the biggest reasons not to use this approach, and while typing:

List newList = new ArrayList();
newList.addAll(listOne);
newList.addAll(listTwo);

is a little more typing, it's a bit easier to read, which helps a lot in understanding or debugging code.