Java ArrayList copy

Question

I have an ArrayList l1 of size 10. I assign l1 to new list reference type l2. Will l1 and l2 point to same ArrayList object? Or is a copy of the ArrayList object assigned to l2?

When using the l2 reference, if I update the list object, it reflects the changes in the l1 reference type also.

For example:

List<Integer> l1 = new ArrayList<Integer>();

for (int i = 1; i <= 10; i++) {

    l1.add(i);

}

List l2 = l1;

l2.clear();

Is there no other way to assign a copy of a list object to a new reference variable, apart from creating 2 list objects, and doing copy on collections from old to new?

Answer 1

Yes, assignment will just copy the value of l1 (which is a reference) to l2. They will both refer to the same object.

Creating a shallow copy is pretty easy though:

List<Integer> newList = new ArrayList<>(oldList);