Explanation of “ClassCastException” in Java

Question

I read some articles written on \"ClassCastException\", but I couldn\'t get a good idea on that. Is there a good article or what would be a brief explanation?

Answer 1

Straight from the API Specifications for the ClassCastException:

Thrown to indicate that the code has attempted to cast an object to a subclass of which it is not an instance.

So, for example, when one tries to cast an Integer to a String, String is not an subclass of Integer, so a ClassCastException will be thrown.

Object i = Integer.valueOf(42);
String s = (String)i;            // ClassCastException thrown here.