Question

Namely, without referencing the same object, I need to copy values of elements of one list into another list. These are the lists:

List<Integer> listA = new ArrayList<Integer>();
List<Integer> ListB = new ArrayList<Integer>();

listA = (added some values);

listB = (do what?)...

PS. I appologize for beginner’s question, but I have never done such a thing.

Answer 1

You can try and give a look at the Collections.copy method:

public static void copy(List dest,
List src)

Copies all of the elements from one list into another. After the operation, the index of each copied
element in the destination list will be identical to its index in the
source list. The destination list must be at least as long as the
source list. If it is longer, the remaining elements in the
destination list are unaffected. This method runs in linear time.

Parameters: dest – The destination list. src – The source list.

Note: The above should work for simple data types such as Integers, however, if you have your own objects which might in turn reference other objects, you will have to iterate over each object and copy it separately.