domain

You can get the Domain from the Application Settings section in the Auth0 dashboard.

client_id

You can get the Client ID from the Application Settings section in the Auth0 dashboard.

client_secret

You can get the Client Secret from the Application Settings section in the Auth0 dashboard.

Gain insights into integrating Auth0 with Java Servlets. Learn configurations, project structure, and servlet implementation for seamless authentication with a hands-on sample application.

Intergrate Auth0 with Java servlet Application.jpg

auth0Tarball.tar.gz

java-servlet

login-servlet

callback-servlet

home-servlet

logout-servlet

java-servlet-original

Auth0 is a flexible, drop-in tool that lets you add authentication and authorization services to your applications. It allows you to authenticate and authorize apps and APIs with any identity provider running on any stack, device, or cloud. It makes it easy for you to give your users the ability to authenticate with the credentials that they are most familiar with.

This course walks you through the integration of Auth0 login into the Java servlet application. You will first be guided through the necessary configurations that you need to make on the Auth0 platform. After that, you will learn about the project structure and implementation of different servlets in detail by looking at a sample login application. The course will also explain the workflow of the different servlets coordinating with each other to successfully authenticate the users and land them on the homepage. You will be interacting with the sample login application throughout the course for a hands-on experience.

Integrate Auth0 with Java Servlet Application

Let's try to understand the different components of this Login application.

The project contains a single JSP: the ***home.jsp***. This JSP displays the token associated with the user after a successful login and provides the option to log out.

The project contains a [WebFilter](https://docs.oracle.com/javaee/7/api/javax/servlet/annotation/WebFilter.html) called ***Auth0Filter.java***, which will check for existing tokens before giving the user access to our protected `/portal/*` path. The paths referred to by `/portal/*` are our protected paths that can only be accessed by authorized users. If the tokens don't exist, the request will be redirected to the `LoginServlet`.

The project contains four servlets:

1. ***LoginServlet.java***: This servlet is invoked when the user attempts to log in. It uses the `client_id` and `domain` parameters to create a valid Authorize URL and redirects the user to this URL. The Authorize URL basically points to the Callback URL, the URL ending with `/callback` which we set up in the Auth0 dashboard.

2. ***CallbackServlet.java***: After the user attempts to log in, the `LoginServlet` redirects the user to the Callback URL. The `CallbackServlet` captures these requests and processes the data to obtain the credentials. If the login was successful, the credentials are saved to the request's `HttpSession`. We will talk about `CallbackServlet` more in the next lesson.

3. ***HomeServlet.java***: This servlet reads the previously saved tokens and shows them on the ***home.jsp*** resource.

4. ***LogoutServlet.java***: It is invoked when the user clicks the logout link. The servlet invalidates the user session and redirects the user to the login page, handled by the `LoginServlet`.

Lastly, the project defines a helper class: the `AuthenticationControllerProvider` which is responsible for creating new instances of `AuthenticationController`. This controller can be safely reused because it's very simple and doesn't keep any context. You can also choose to create a new one every time it's needed. We will talk about `AuthenticationController` in detail in the next lesson.

Let's try to understand the complete workflow of our Java servlet application with the help of the following demonstration.

Learn about the sample login application we will be interacting with.

Introduction

Auth0 Integration

Conclusion

Java Servlet Application

Project structure