Super Keyword in Java | Example

→ super keyword is a reference variable that is used to refer immediate parent class objects.

Usage of Super Keyword

Variable.
Method.
Constructor

1) Super keyword use in Variable

→ super keyword allow to access the data member, field of parent class. same fields or data member of parent class and child class.

Example:

class Vehicle { 
    int maxSpeed = 180; 
 } 
class Car extends Vehicle { 
    int maxSpeed = 210; 
     void display() {  
        System.out.println("Maximum Speed: " +maxSpeed); 
        System.out.println("Maximum Speed: " + super.maxSpeed); 
    } } 
  class TestSuper1{ 
  public static void main(String[] args){ 
        Car c = new Car(); 
        c.display(); 
    } } 

Output :-

Note :-To access the parent property, so use super keyword.

2) Super keyword use in Method

→ super keyword can also be used to immediate parent class method. same named methods of parent and child class .

Example:

/* Base class Person */
class Person{ 
    void message() { 
        System.out.println("This is Good person"); 
    } } 
 /* Subclass Student */
class Student extends Person{ 
    void message(){ 
        System.out.println("This is not good person"); 
    }
  void display(){ 
        message(); 
        super.message(); 
    } } 
 class TestSuperMethod{ 
    public static void main(String args[]){ 
        Student s = new Student(); 
        s.display(); 
    } } 

Output :-

3) Super keyword use in Constructor

→ super keyword can also be used to invoke the parent class constructor

Example:

 class Person{ 
    Person(){ 
        System.out.println("This Person is Very good."); 
    } } 
class Student extends Person { 
    Student(){        
        super();  
        System.out.println("This Person is Not Very good"); 
    }} 
class SuperConstructor{ 
    public static void main(String[] args){ 
        Student s = new Student(); 
    } } 

Output :-

Real Example :-

Example:

class Person{  
int id;  
String name;  
Person(int id,String name){  
this.id=id;  
this.name=name;  
}}  
class Employe extends Person{  
float salary;  
Employe(int id,String name,float salary){  
super(id,name);//reusing parent constructor  
this.salary=salary;  
}  
void display(){System.out.println(id+" "+name+" "+salary);}  
}  
class RealExample{  
public static void main(String[] args){  
Employe e1=new Employe(01,"Jon",40000f);  
e1.display();  
}}  

Output :-

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OOPs Concepts

Super Keyword in Java | Example

Usage of Super Keyword

1) Super keyword use in Variable

2) Super keyword use in Method

3) Super keyword use in Constructor

Real Example :-