Arrays$ArrayList cannot be cast to java.util.ArrayList in java [duplicate]

Question

convert array into listand that list convert to arrayList

    int[] array = new int[5];
    array[0] = 1;array[1] = 2;array[2] = 3;array[3] = 4;array[4] = 5;
    List list = Arrays.asList(array);
    ArrayList alist = new ArrayList();
    alist =  (ArrayList) list;

Exception

Exception in thread "main" java.lang.ClassCastException: java.util.Arrays$ArrayList cannot be cast to java.util.ArrayList

Answer 1

The class Arrays has its own private static class ArrayList<E> internally. It doesn't relate to java.util.ArrayList class. These classes are different.

It is likely that you are confused about this line in the source code:

return new ArrayList<>(a);

It is just a creation of nested class. There is no java.util.ArrayList import there.

Answer 2

Arrays.asList returns an object of type java.util.Arrays$ArrayList but it is not extends ArrayList

just change the last two lines:

List alist = list;

and it will be fine