REST API in Java with JAX-RS and Jersey using JWT Authentication.

Filter Checking the JSON Web Token

The magic hides behind JsonTokenNeeded. Well, not really, it hides behind the BearerTokenFilter. JsonTokenNeeded is just a JAX-RS name binding (think of it as a CDI interceptor binding), so it’s just an annotation that binds to a filter.

1 - Gets the HTTP Authorization header from the request and checks for the JSON Web Token (the Bearer string)

2 - It validates the token (using the JWT library)

3 - If the token is valid, the method is invoked and provided correct result of request.

4 - If the token is invalid, a 401 Unauthorized is sent to the client

Installation

Install dependencies:

$ mvn clean install

Start the server:

$ mvn tomcat8:run

Usage example

http://localhost:8081/api