Java ClassCastException is a runtime exception that occurs when an attempt is made to cast an object to a type it is not compatible with. This happens when a class is improperly cast to another class, which can be detected during runtime. ClassCastException is a subclass of Java RuntimeException, and it typically arises when working with generics or object casting in Java programs. Introduced in Java 1995 with Java 1.0, it is a common issue in type conversion when the type of the object is not properly checked.

https://docs.oracle.com/javase/8/docs/api/java/lang/ClassCastException.html