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Hello... Please I'm a little bit confused by this statement: "But if you have a group of different Animals and want to downcast them all to a Cat, then there's a chance that some of these Animals are actually Dogs, so the process fails." Does it mean that, if we have for instance, Animal b = new Dog(); And doing this; ((Cat)b).makeSound(); will fail?

6th Jun 2017, 8:58 PM
Daniel Graham
1 Réponse
+ 3
Yes it will fail. Think of it this way. You are assigning the value, 'Dog' to the variable Animal. This is allowed, since a Dog is an Animal. Then, you cast the variable to a Cat. But it still has the value of Dog!! A Cat is a Dog?! This is madness! Error! That's why you may see things like this: if(myAnimal instanceof Dog) ((Dog)myAnimal).makeSound(); else if(myAnimal instanceof Cat) ((Cat)myAnimal).makeSound();
6th Jun 2017, 9:20 PM
Rrestoring faith
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