What does the 'super' keyword do in Java?

In Java, the super keyword is used to refer to the superclass (parent class) of the current object. It serves several purposes:

1. Accessing Superclass Methods: You can use super to call methods from the superclass that have been overridden in the subclass. This allows you to invoke the original method implementation.

   class Animal {
       void eat() {
           System.out.println("Animal eats");
       }
   }
   
   class Dog extends Animal {
       void eat() {
           super.eat(); // Calls the eat method of Animal
           System.out.println("Dog eats");
       }
   }
   
   public class Main {
       public static void main(String[] args) {
           Dog dog = new Dog();
           dog.eat(); // Output: Animal eats
                       //         Dog eats
       }
   }

2. Accessing Superclass Constructors: You can use super() to call a constructor of the superclass. This is often done to initialize inherited fields.

   class Animal {
       Animal() {
           System.out.println("Animal constructor");
       }
   }
   
   class Dog extends Animal {
       Dog() {
           super(); // Calls the constructor of Animal
           System.out.println("Dog constructor");
       }
   }
   
   public class Main {
       public static void main(String[] args) {
           Dog dog = new Dog(); // Output: Animal constructor
                                //         Dog constructor
       }
   }

3. Accessing Superclass Fields: If a subclass has a field with the same name as a field in its superclass, you can use super to refer to the superclass field.

   class Animal {
       String name = "Animal";
   }
   
   class Dog extends Animal {
       String name = "Dog";
   
       void printNames() {
           System.out.println(name);        // Prints "Dog"
           System.out.println(super.name);  // Prints "Animal"
       }
   }
   
   public class Main {
       public static void main(String[] args) {
           Dog dog = new Dog();
           dog.printNames();
       }
   }

In summary, the super keyword in Java is a powerful tool for accessing superclass methods, constructors, and fields, allowing for better code reuse and organization in object-oriented programming.