resolve a java.util.ArrayList$SubList notSerializable Exception

Question

I am using SubList function on an object of type List. The problem is that I am using RMI and because the java.util.ArrayList$SubList is implemented by a non-serializable class I got the Exception described above when I try to pass the resulting object to a remote function taking as an argument a List as well. I've seen that I should copy the resulting List to a new LinkedList or ArrayList and pass that.

Does anyone know a function that helps as to easily do that for this for example ?

List<String> list = originalList.subList(0, 10);

Aceydeucy

You can copy a list very easily. The ArrayList constructor will accept an existing collection (including your sublist) as an argument, and perform a copy. – Vereen

@Vereen stole my answer. Just copy it to a list you know is serializable. – Holdover

Ok, thnaks this is what I've done using an ArrayList!! – Aceydeucy

@Vereen Why don't you post your comment as an answer? Then the OP can accept your answer. – Giroux

Answer 1

It's because, List returned by subList() method is an instance of 'RandomAccessSubList' which is not serializable. Therefore you need to create a new ArrayList object from the list returned by the subList().

List<String> list = new ArrayList<String>(originalList.subList(0, 10));

Imray

Answer 2

The solution was simply this code:

ArrayList<String> list = new ArrayList<String>();
list.addAll(originalList.subList(0, 10));

Aceydeucy

The other proposed solution is better because it will pre-allocate the full size once, instead of possibly having to allocate the default size & then re-allocate space for the sublist while adding the elements. – Immortelle

If you care about performance you should not create twice the same sub-list – Buffalo