casting Object array to Integer array error

casting, java

Solution

Ross, you can use Arrays.copyof() or Arrays.copyOfRange() too.

Integer[] integerArray = Arrays.copyOf(a, a.length, Integer[].class);
Integer[] integerArray = Arrays.copyOfRange(a, 0, a.length, Integer[].class);

Here the reason to hitting an `ClassCastException` is you can't treat an array of `Integer` as an array of `Object`. `Integer[]` is a subtype of `Object[]` but `Object[]` is not a `Integer[]`.

And the following also will not give an `ClassCastException`.

Object[] a = new Integer[1];
Integer b=1;
a[0]=b;
Integer[] c = (Integer[]) a;

Problem

Original source