Let’s say we have an
ArrayList that stores items in a user’s online shopping cart. As the user navigates through the site and adds items, their cart grows bigger and bigger.
If we wanted to display the number of items in the cart, we could find the size of it using the
ArrayList<String> shoppingCart = new ArrayList<String>(); shoppingCart.add("Trench Coat"); System.out.println(shoppingCart.size()); // 1 is printed shoppingCart.add("Tweed Houndstooth Hat"); System.out.println(shoppingCart.size()); // 2 is printed shoppingCart.add("Magnifying Glass"); System.out.println(shoppingCart.size()); // 3 is printed
In dynamic objects like
ArrayLists, it’s important to know how to access the amount of objects we have stored.
Detectives do a lot to solve a case. But who has more to do?
Print out the size of each detective’s to-do
sherlocksToDosfor Sherlock Holmes
poirotsToDosfor Hercule Poirot
So who has more to do? Print the name of the detective whose to-do list is longer. Was it Sherlock or Poirot?