What is the need of abstract class?

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The classes which are defined with the abstract keyword are known as abstract classes. Abstact classes contain one or more abstract methods. An abstract method is declared but contains no implementation. It requires subclasses to provide implementations for the abstract methods. Abstraction is a feature...
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The classes which are defined with the abstract keyword are known as abstract classes. Abstact classes contain one or more abstract methods. An abstract method is declared but contains no implementation. It requires subclasses to provide implementations for the abstract methods. Abstraction is a feature in object-oriented programming languages like Java, where the implementation details are hidden. 'Abstract' keyword is used to create abstract classes and methods. Abstract classes in Java are similar to the interfaces, except that it can contain default method implementation. Abstract classes only tell the programmer what to do and not how to do it. Abstract classes are mainly required when we have to share some common operations between certain subclasses. They are primarily used for those sets of classes that are closely related to each other. For example, if you talk about shape, then it is abstract because the shape can be anything square, round, triangle etc. But when we say triangle shape, then it is specific. The primary purpose of using abstract classes is to enhance polymorphism feature. That means the code will work for any subclass of the abstract superclass. Abstract classes are used the same as super-classes EXCEPT that an Abstract class cannot be instanced itself, but only through classes that implement it. read less
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