Why Downcasting throws Exception?

Question

In java:

Base b = new Base();
Derived d = (Derived)b; 

throws ClassCastException. Why? Why downcasting throws Exception<

Answer 1

To downcast in Java and avoid run-time exceptions, take a reference of the following code:

if (animal instanceof Cat) {
  Cat cat = (Cat) animal;
}

Here, Animal is the parent class and Cat is the child class.

instanceof is a keyword that is used for checking if a reference variable is containing a given type of object reference or not.