It acts as a bridge between View and Model i.e. The servlet is a controller in the MVC pattern. Further, you can watch the video for the explanation. The numbers in blue color indicate the sequence of execution.

Simple Java Registation Page using MySQL & MVCīefore we begin with actual coding, you may want to take a look at the list of files and JARs used in this example and how they are placed in eclipse IDE (open-source java editor).

Since HTTP and Web Server both are stateless, you would use some unique information (sessionID) to create a session and this sessionID is passed between server and client in every request and response.

You cannot really track who made a request and when the request terminated. The session helps us to maintain a state between the client and the server and it can consist of multiple requests and responses between the client and the server. HTTP is a stateless protocol which means the connection between the server and the browser is lost once the transaction ends. In this example, you are going to see 3 roles – Admin, Editor, and user. When you want to segregate the access level for each user based on their roles like administrator, teacher, student etc in your application you would want to assign a specific role to each user who is logging in so that it is easier to manage large applications. If you are a beginner and if you are looking for a simple Java login and Registration example you can click on the respective links. This example is an advanced version of java login page. You can go through this link to know how to create a database and tables in MySQL using an open-source software Wamp server. This role-based Java Login example contains JSP, Java servlets, session objects, and MySQL database server.

Sample java web application source code