casting Arrays.asList causing exception: java.util.Arrays$ArrayList cannot be cast to java.util.ArrayList

Question

I\'m new to Java and am trying to understand why the first code snippet doesn\'t cause this exception but the second one does. Since a string array is passed into Arrays.as

Answer 1

If you want to use your property as ArrayList<'T'> you need only declare there and create a getter.

    private static ArrayList bandsArrayList;

    public ArrayList getBandsArrayList() {
        if (bandsArrayList == null) {
            bandsArrayList = new ArrayList<>();

            String[] bands = {"Metallica", "Iron Maiden", "Nirvana"};
            bandsArrayList.addAll(Arrays.asList(bands));
        }
        return bandsArrayList;
    }

Initializes the variable and use the method [addAll (Collection collection)](http://developer.android.com/intl/pt-br/reference/java/util/ArrayList.html#addAll(java.util.Collection))