Revisiting users logged in to a service

In Chapter 2, Arrays: Foundational Structures, we created an app to keep track of users logged into a web service, using an array as the underlying data structure containing the User objects. However, this design can be greatly improved upon by using a list data structure. Let's revisit the users logged into a service problem here, and by replacing the class array with a list, we will see that our original code is both abbreviated and more readable in most cases.


In this example, we have replaced the User[] object with a List<User> object. Much of this refactor is obvious, but three lines of code should be noted. First, in the CanAddUser() method, we have replaced 15 lines of code with 2 lines of code by ...

Get Everyday Data Structures now with the O’Reilly learning platform.

O’Reilly members experience live online training, plus books, videos, and digital content from nearly 200 publishers.