Magic of Polymorphism in Object-Oriented Programming

I am Naimish Trivedi, I have a far experience in native and hybrid programming. I have presented the programming concept here in a simple and easy way from my experience. This will be very useful for beginner Devs and Students.

We have seen Inheritance in previous article now in this article, we will learn about Polymorphism in OOPs.

Polymorphism in Java is a concept by which we can perform a single action in different ways. Polymorphism is derived from 2 Greek words: poly and morphs. The word "poly" means many and "morphs" means forms. So polymorphism means many forms.

Types of Java Polymorphism

• Compile-time Polymorphism
• Runtime Polymorphism

1. Compile-time Polymorphism :

It is also known as static polymorphism. This type of polymorphism is achieved by method overloading.

Method Overloading :

Method overloading allows a class to have multiple methods with the same name but different parameter lists. The compiler determines which method to call based on the number and types of arguments passed to the method at compile time. Method overloading is a form of compile-time polymorphism because the decision about which method to call is made by the compiler at compile time.

For Example :

2. Runtime Polymorphism :

It is also known as Dynamic Method Dispatch. It is a process in which a function call to the overridden method is resolved at Runtime. This type of polymorphism is achieved by Method Overriding.?

Method Overriding :

Method overriding allows a subclass to provide a specific implementation of a method that is already defined in its superclass. When a subclass overrides a method, it provides its own implementation of the method, which is used instead of the superclass's implementation when the method is called on an object of the subclass. The method signature (name and parameters) must be the same in both the superclass and the subclass for method overriding to occur.

For Example :

Advantages of Polymorphism in Java :

1. Code Reusability: Polymorphism enables the reuse of code across different classes by allowing methods to be invoked on objects of different types through a common interface or superclass.
2. Flexibility and Extensibility: Polymorphism allows for flexible and extensible code design. New subclasses can be added without modifying existing code, and existing methods can be reused with different implementations.
3. Simplified Code Structure: Polymorphism promotes a simpler and more modular code structure by encapsulating behavior within objects and promoting the use of interfaces and abstract classes to define common behavior.
4. Dynamic Method Binding: Polymorphism facilitates dynamic method binding, where the appropriate method implementation is determined at runtime based on the actual type of the object. This allows for runtime flexibility and adaptability.
5. Enhanced Maintainability: Polymorphism promotes better code organization and modularization, making it easier to maintain and update codebases over time. Changes to one part of the codebase are less likely to affect other parts, leading to more manageable code.

Disadvantages of Polymorphism in Java :

1. Complexity: Polymorphism can introduce complexity, especially in larger codebases with multiple subclasses and overridden methods. Understanding the flow of execution and determining which method implementation will be called at runtime can be challenging.
2. Performance Overhead: Dynamic method binding, which is a key feature of polymorphism, can incur a slight performance overhead compared to static method binding. This overhead is typically negligible in most applications but may become noticeable in performance-critical systems.
3. Potential for Run-time Errors: Polymorphism relies on dynamic method dispatch to determine the appropriate method implementation at runtime. While this provides flexibility, it also introduces the possibility of run-time errors if method implementations are not correctly overridden or if there are inconsistencies in method signatures.
4. Hidden Complexity: Polymorphism can lead to hidden complexity, especially when method invocations are dynamically bound and the actual method implementation is determined at runtime. This can make code harder to understand and debug, particularly for developers unfamiliar with the codebase.
5. Overuse and Abstraction Leakage: Overuse of polymorphism and excessive abstraction can lead to abstraction leakage, where implementation details leak through abstractions, making the codebase harder to understand and maintain. It's essential to strike a balance between abstraction and concreteness when using polymorphism.

Overall, while polymorphism offers significant benefits in terms of code reusability, flexibility, and maintainability, it's essential to use it judiciously and understand its potential drawbacks to ensure that it enhances rather than complicates the design and implementation of Java applications.

That's it for now.

Thanks,

Stay tuned for another chapter on OOPs Concept.