what's method overriding

// Base Class 
class Parent { 
    void show(){ 
        System.out.println("Parent's show()"); 
    } 
} 
// Inherited Class 
class Child extends Parent { 
    // This method overrides show() of Parent Class
    @Override
    void show(){ 
        System.out.println("Child's show()"); 
    } 
}
// Main class 
class Main { 
    public static void main(String[] args){ 
        Parent obj = new Child(); 
		// Calling Child Class Method
        obj.show(); 
    } 
}

Overriding means same method name and same parameter, 
occur in different class that has inheritance relationship. 
we use method overriding to implement specific functionality to the method.

Example: get method
WebDriver driver = new ChromeDriver();
driver.get("URL") ==> opens the url from chrome

WebDriver driver = new FireFoxDriver();
driver.get("URL") ==> opens the url from Firefox

we can only override instance methods and method override 
takes place in sub class.
instance method that we are going to override cannot be private and final

public static void main(String[] args) {
  int menuOption;
  int foodItem = 0;
  input = new Scanner(System.in);
  double runningTotal=0;
  do{
    menu();
    menuOption = input.nextInt();
    switch(menuOption){
      case 1:
        foodItem = 1;
        runningTotal += itemPrice(foodItem);
        break;
      case 2:
        foodItem = 2;
        runningTotal += itemPrice(foodItem);
        break;
      case 3:
        foodItem = 3;
        runningTotal += itemPrice(foodItem);
        break;
      case 4:
        done(runningTotal);
        break;
      default:
        System.out.println("Invalid option.");
    }
  } while(ordering);
  System.out.println("Total amount: " + runningTotal);
}