Is this bizarre or am I expecting too much from Java language?

Question

Yesterday I noticed that when I use Arrays.sort() to sort contents of an ArrayList (containing objects of Comparable type with compareTo implemented correctly) the sort routine did not return a sorted list. After looking at everything for hours the problem seems to be that the sort routine works on a copy of the original list created through ArrayList.toArray(). The Object [ ] that is the result of toArray() is sorted by the sort routine but it is never put back in the original ArrayList! So what is a person to do in order to use the list after it's sorted? Am I to switch to using Object [ ] instead of the original ArrayList or manually copy the sorted contents of Object [ ] into the original list ?
May be I'm missing something but this does seem a bit inconvenient and bizarre.
I would appreciate if someone could enlighten me and tell me of a better way if there is one.
Thanks in advance

Answer 1

Labelling your results "inconvenient and bizarre" may be a bit strong as both the Arrays.sort() and the ArrayList.toArray() methods do work as advertised. What you are probably missing is the fact that the ArrayList.toArray() method returns a copy of the array buffer that is used to store the actual elements of the given ArrayList. Part of the reason for this is that that internal array is often greater in size than the number of elements it holds; the ArrayList.toArray() returns an array that is exactly the size of the ArrayList (as opposed to the capacity).
As to a better way of doing things, check out the Collections class; it contains a collection of utility methods for the Collection extensions and implementations, much like the Arrays class contains utility methods for operating on arrays.
Shaun