Polymorphism in Java

Polymorphism, derived from the Greek words “poly” meaning many and “morph” meaning form .Polymorphism in Java refers to the ability of objects to take on multiple forms or the ability of methods to behave differently based on the object that calls them. It allows objects of different classes to be treated as objects of a common superclass, enabling flexibility and extensibility in code design.

In the below PDF we discuss about Polymorphism in Java in detail in simple language, Hope this will help in better understanding.

Types of Polymorphism in Java

In Java Polymorphism is mainly divided into two types:

1. Compile-time Polymorphism (Method Overloading):
Method overloading allows a class to have multiple methods with the same name but different parameters. During compilation, the Java compiler determines which method to invoke based on the number and type of arguments passed. This form of polymorphism is resolved at compile time, hence the name compile-time polymorphism.

Example of method overloading:

public class Calculator {
public int add(int a, int b) {
return a + b;
}
public double add(double a, double b) {
return a + b;
}
}

2. Runtime Polymorphism (Method Overriding):
Method overriding occurs when a subclass provides a specific implementation of a method that is already defined in its superclass. The method in the subclass must have the same name, return type, and parameters as the method in the superclass. At runtime, the JVM determines which method to execute based on the type of object.

Example of method overriding:

class Animal {
void sound() {
System.out.println("Animal makes a sound");
}
}
class Dog extends Animal {
void sound() {
System.out.println("Dog barks");
}
}

In the above example, when a Dog object invokes the sound() method, it executes the overridden method defined in the Dog class, producing the output “Dog barks”.

Benefits of Polymorphism in Java:

Code Reusability: Polymorphism allows developers to reuse code by creating generic methods or classes that can be adapted to work with different data types or objects.
Flexibility: Polymorphism enables the creation of modular and extensible code, making it easier to accommodate changes and enhancements in the future.
Simplified Maintenance: By promoting code reuse and modularity, polymorphism reduces the complexity of code maintenance and debugging, leading to more efficient software development.

Conclusion

Polymorphism is a fundamental concept in Java programming that enhances code flexibility, reusability, and maintainability. By understanding and implementing polymorphism effectively, developers can write cleaner, more modular code that is easier to maintain and extend. Whether it’s through method overloading or method overriding, polymorphism empowers Java developers to build robust and scalable applications that meet the evolving needs of users and stakeholders.

Must Read: OOPs Concepts In Java, Classes & Objects in Java and Abstraction in Java