Why Does Casting an Object Array to an Integer Array Result in a ClassCastException?

Why the Casting from Object Array to Integer Array Raises a ClassCastException

The following code snippet encounters an error:

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

The error, "java.lang.ClassCastException: [Ljava.lang.Object; cannot be cast to [Ljava.lang.Integer;", occurs in the last line.

Reason:
The problem arises because you cannot treat an array of integers as an array of objects. While Integer[] is a subtype of Object[], Object[] is not a subtype of Integer[].

Therefore, attempting to cast an Object[] to an Integer[] results in a ClassCastException.

Alternative Code:
To address this issue, use one of the following methods:

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

Alternatively, you can prevent the ClassCastException by ensuring that the array elements are all of type Integer, as in the following correct code:

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

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