[PDF] abstract class implement abstract class

We cannot create objects of an abstract class. To implement features of an abstract class, we inherit subclasses from it and create objects of the subclass. A subclass must override all abstract methods of an abstract class. However, if the subclass is declared abstract, it's not mandatory to override abstract methods.
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  • How do you implement abstraction using abstract class?

    It's common to have some implementation in abstract classes. If there is no implementation at all, consider using an interface instead of an abstract class. Perfectly fine to implement some methods and leave others abstract. If all methods had to be abstract, you might as well use an interface for it.

  • Should abstract class have implementation?

    Classes such as Number, which implement abstract concepts and should not be instantiated, are called abstract classes. An abstract class is a class that can only be subclassed--it cannot be instantiated.

  • Which class implements the abstract concept?

    A class can implement multiple interfaces. A class can extend only one abstract class.
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Implements and Extends implements –. “dashed line” Interface Abstract Class



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abstract method in abstract class. ? If a subclass of an abstract superclass does not implement all the abstract methods the.



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// Note: We do not implement Payable method getPaymentAmount here so. // this class must be declared abstract to avoid a compilation error. } // end abstract 



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it its implementation must abstract over variable subparts of behavior. Class Design Principles: The Open-Closed Principle (OCP) 



abstract cl-ass Boat private String myName private int myCapacj_ty

methods need to be implemented we cannot instantiate an abstract class. Like the interface