Why can we change the unmodifiable list if we have the original one?

Question

By looking at the code of Collections class, i got to know that when we are using the method unmodifiableList(List list) or unmodifiableCollection(Coll

Answer 1

I Found one way to do this is

List unmodifiableList = Collections.unmodifiableList( new ArrayList(modifiableList));

List strings = new ArrayList();
        // unmodifiable.add("New string");
        strings.add("Aha 1");
        strings.add("Aha 2");
        List unmodifiable = Collections.unmodifiableList(strings);
        List immutableList = Collections.unmodifiableList(new ArrayList<>(strings));
        // Need some way to fix it so that Strings does not Modify
        strings.add("Aha 3");
        strings.add("Aha 4");

        strings.remove(0);

        for (String str : unmodifiable) {
            System.out.println("Reference Modified :::" + str);
        }

        for (String str : immutableList) {
            System.out.println("Reference Modified :::" + str);
        }