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Java

Posted by Matthew Francis
Matthew Francis
6,967 Points

Newbie - Is my understanding correct on downcasting a class' ancestor?

class animal{}

class Mammal extends Animal{}

class Cat extends Mammal{}

Mammal m = new Mammal();
Cat c = (Cat)m;

From what I've read if you Downcast a class' ancestor like this, it will give you an error.

But then, why can you downcast an Object superclass to any class? does Java have an exception that only allows the Object superclass to be downcasted to any class?

eg:

  public void method(Object obj){
    Cat other = (Cat) obj;
....
}