As described in a previous article about getting an Apereo CAS application up and running, we used the default username and password to log in to the CAS. But in a real-world scenario, we need to implement some sort of mechanism to authenticate a user. It is more common to use an authentication handler for this purpose. In this article, we are going to look into the details of implementing a custom authentication handler in an Apereo CAS (hereafter it will be simply referred to as CAS) application.
Note: Additional implementational details are available inside the following code blocks as Java comments.