private static class ArrayList in java.util.Arrays - Why?

Question

In java.util.Arrays there is a private static class called "ArrayList" defined. It is only referred from Arrays.asList method.

What is the benifit of doing this? Why is java.util.ArrayList not referred instead?

Code below:

   /**
    * @serial include
    */
      private static class ArrayList<E> extends AbstractList<E>
implements RandomAccess, java.io.Serializable

Answer 1

Despite the fact that the private static ArrayList class shares the same name as java.util.ArrayList, they behave differently by design. Given that, there's no reason that the implementations should be one and the same.

Arrays#asList() returns a fixed-size list backed by the specified array. (Changes to the returned list "write through" to the array.) This method acts as bridge between array-based and collection-based APIs.