Types of Polymorphism
- Compile-Time Polymorphism
- Runtime Polymorphism
Compile-Time Polymorphism
Compile-time polymorphism, also known as static polymorphism, is a type of polymorphism that is resolved during the compilation of the program. In C++, it is primarily achieved through function overloading and operator overloading.
Example
int add(int a, int b) {
return a + b;
}
double add(double a, double b) {
return a + b;
}
In this code, the display() function is overloaded with two different parameter lists.
Runtime Polymorphism
Runtime polymorphism, also known as dynamic polymorphism, is a type of polymorphism that is resolved during the execution of the program. It is mainly achieved in C++ through inheritance and virtual functions.
Example
class Base {
public:
virtual void show() {
std::cout << "Base class" << std::endl;
}
};
class Derived : public Base {
public:
void show() override {
std::cout << "Derived class" << std::endl;
}
};
In this example, the sound() method in the Dog class overrides the same method in the Animal class.
Practical Applications of Polymorphism
Polymorphism is at the heart of many fundamental design patterns in OOP, like Strategy, State, and Template Method patterns. It's used in various real-world applications, from creating UI controls to designing complex software systems.
Frequently Asked Questions
What is polymorphism in OOP?
Polymorphism is an OOP principle that allows objects to take on many forms. It enables a single interface to represent different types of entities.
Is polymorphism inheritance?
Polymorphism is not the same as inheritance, but they are closely related. Inheritance allows a class to inherit properties from another class, while polymorphism allows methods to be used interchangeably, depending on the object's type.
What is the principle of polymorphism?
The principle of polymorphism allows objects of different classes to be treated as objects of a common superclass. It enables the same interface or method to be used for different underlying forms (data types). This principle fosters code flexibility and reusability by allowing a single function to operate on objects of various types, with the exact behavior determined at runtime or compile-time. Polymorphism is essential for implementing dynamic and scalable systems in object-oriented programming, as it abstracts and simplifies interactions between objects, reducing code complexity.
Why is polymorphism important?
Polymorphism makes programs more flexible and scalable. It reduces complexity by allowing the same interface to be used for different types, thus promoting code reusability and clean, modular design.
Conclusion
In this article, we have discussed what polymorphism is. Polymorphism is a cornerstone of object-oriented programming in C++, providing the flexibility and power to write more dynamic, maintainable, and scalable code. Polymorphism reduces redundancy and enhances code reusability by allowing functions and operators to operate in different ways depending on the context.