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super keyword in Java


  • super variable refers immediate parent class instance.
  • super variable can invoke immediate parent class method.
  • super() acts as immediate parent class constructor and should be first line in child class constructor.

When invoking a superclass version of an overridden method the super keyword is used.

Example

class Animal {
   public void move() {
      System.out.println("Animals can move");
   }
}
class Dog extends Animal {
   public void move() {
      super.move(); // invokes the super class method
      System.out.println("Dogs can walk and run");
   }
}
public class TestDog {
   public static void main(String args[]) {
      Animal b = new Dog(); // Animal reference but Dog object
      b.move(); // runs the method in Dog class
   }
}

Output

This will produce the following result −

Animals can move
Dogs can walk and run