Abstract class

Question

Abstract class. After learning in solo I can't understand what is abstract, can u explain me about it? Maybe some examples where im nessesary to use abstract class.

Answer 1

An abstract class cannot be implemented and it works like a "kind class". For example. There is a lot kinds of birds, and if anyone asks you to draw a bird, you probably will draw one of this kinds of birds. That's because bird is not an individual, but a group with same caracteristcs. So, in OOP, bird will be an abstract class and duck a class that inherit atributes and methods from bird. Now you can create a object duck with atributes you want, like weight, color, and so on.

You will probably use more abstract class when you are creating a "group class".

Do I answered your question?

Answer 2

http://java-w3schools.blogspot.nl/2015/04/abstraction-abstract-class-methods-in.html?=1

Answer 3

Let's say you're working on a project and you think of some functions or methods that you would need, but haven't thought about exactly what code would go in it. So a simple solution would be to create a separate class that contains all these methods but doesn't specify any code inside the method itself. These methods are called abstract methods; and the class that contains more than 1 abstract method is called an abstract class

Answer 4

Let's say you have an animal class. Every animal class inherits from it. If you want to create an dog you will make "class dog extends animal" and then "dog dog1 = new dog();", but don't you want to prevent creating an object from the animal class? Which weird living thing would be an object from the animal class? Would it have 5 heads and 20 legs? Could it spit fire? You don't want " animal animal1 = new animal();". You just want classes that inherit from it. That's one example I can think of right now. That's where thr keyword abstract comes in handy.

Answer 5

thanks!