💡Polymorphism-

💡Definition –

Generally means “one name, many forms”
-in java, polymorphism means “one name of multiple methods, but different outputs.

💡Rule of polymorphism-

method name must be same

💡Types of polymorphism-

1- Compile time polymorphism/static method binding
2- Runtime polymorphism/dynamic method binding

Quick Comparison between compile-time polymorphism and runtime polymorphism in Java:

	Compile-time Polymorphism	Runtime Polymorphism
Also known as	Static polymorphism	Dynamic polymorphism
Achieved through	Method overloading	Method overriding
Compiler determines method	At compile time	At runtime
Requires inheritance	No	Yes
Performance	Faster and more efficient	Slower and less efficient

💡1- Compile time polymorphism

-Calling method is decided at compile time
– In java, this is achieved by Method Overloading

💡(i) Method overloading

Rules of method overloading-

-only 1 class is required
-parameter must be different
-return type can be different or same

💡2- Runtime polymorphism

-Calling method is decided at runtime
-in java, this is achieved by method overriding

💡(ii) Method overriding

Rules of method overriding-

-at least 2 classes are required
-parameters must be same
-return type must be same

code samples are here

1- Compile time polymorphism


package polymorphism13;

public class ExampleCompilePoly {

void show(int a){
System.out.println("hello the number is "+a);
}

void show(String a){
System.out.println("hello the text is "+a);
}

public static void main(String[] args) {
ExampleCompilePoly e1=new ExampleCompilePoly();
e1.show(25); //will call first show method
}

}

Run this Program ▶️

2- Runtime polymorphism


package polymorphism13;

class A{
void display(){
System.out.println("hi");
}
}

public class ExampleRuntimePoly extends A {

void display(){
System.out.println("bye");
}
public static void main(String[] args) {

ExampleRuntimePoly n1 = new ExampleRuntimePoly();
n1.display(); //will call second display method
}
}

Run this Program ▶️