What is abstract class

Abstract class is an abstract concept derived from the analysis and design of the problem field. It is an abstraction of a series of specific concepts that look different but are essentially the same. Abstract classes are incomplete and can only be used as base classes for type hiding and global variables.

Abstract class definition

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Abstract classes are often It is used to represent the abstract concepts derived from the analysis and design of the problem domain. It is an abstraction of a series of specific concepts that look different but are essentially the same.

Classes usually modified with abstract in programming statements are abstract classes. In C, a class containing pure virtual functions is called an abstract class, which cannot generate objects; in Java, a class containing abstract methods is called an abstract class, which also cannot generate objects.

Abstract class is incomplete, it can only be used as a base class. In the object-oriented approach, abstract classes are mainly used for type hiding and acting as global variables.

In the object-oriented concept, all objects are described by classes, but conversely, not all classes are used to describe objects. If a class does not contain enough information To describe a specific object, such a class is an abstract class.

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