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Published inJan 2016
Reading LevelIntermediate
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ISBN-139781785885693
Edition1st Edition
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Gaston C. Hillar
Gaston C. Hillar
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Gaston C. Hillar

Gaston C. Hillar is Italian and has been working with computers since he was 8 years old. Gaston has a Bachelor's degree in computer science (graduated with honors) and an MBA. Currently, Gaston is an independent IT consultant and a freelance author who is always looking for new adventures anywhere in the world. He was a senior contributing editor at Dr. Dobb's, and has written more than a hundred articles on software development topics. He has received the prestigious Intel Black Belt Software Developer award eight times. He has written many articles about Java for Oracle Java Magazine. Gaston was also a former Microsoft MVP in technical computing. He lives with his wife, Vanesa, and his two sons, Kevin and Brandon.
Read more about Gaston C. Hillar

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Working with typecasting and polymorphism


We can use the same method—that is, the same name and arguments—to cause different things to happen according to the class on which we invoke the method. In object-oriented programming, this feature is known as polymorphism.

For example, consider that we defined a talk method in the Animal class. The different subclasses of Animal must override this method to provide their own implementation of talk.

The Dog class overrode this method to print the representation of a dog barking—that is, a Woof message. On the other hand, a Cat class will override this method to print the representation of a cat meowing—that is, a Meow message.

Now, let's think about a CartoonDog class that represents a dog that can really talk as part of a cartoon. The CartoonDog class would override the talk method to print a Hello message because the dog can really talk.

Thus, depending on the type of the instance, we will see a different result after invoking the same method with...

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Object???Oriented Programming with Swift 2
Published in: Jan 2016Publisher: ISBN-13: 9781785885693

Author (1)

author image
Gaston C. Hillar

Gaston C. Hillar is Italian and has been working with computers since he was 8 years old. Gaston has a Bachelor's degree in computer science (graduated with honors) and an MBA. Currently, Gaston is an independent IT consultant and a freelance author who is always looking for new adventures anywhere in the world. He was a senior contributing editor at Dr. Dobb's, and has written more than a hundred articles on software development topics. He has received the prestigious Intel Black Belt Software Developer award eight times. He has written many articles about Java for Oracle Java Magazine. Gaston was also a former Microsoft MVP in technical computing. He lives with his wife, Vanesa, and his two sons, Kevin and Brandon.
Read more about Gaston C. Hillar