What this book covers

Chapter 1, Setting Up the Environment, helps us create our first functional application, something very similar to a Hello World example, but with some more functionality and very close to the real world. The main aim of this chapter is to familiarize ourselves with the tools we are going to use.

Chapter 2, The Importance of Securing Web Services, goes through all possible models of authentication in the Java platform. For your better understanding, we will go step by step and dive deep into how we can leverage each available authentication model. We will show you how the information is exposed and how it can be intercepted by third parties, and we will play with Wireshark, which is a very good tool to explain it.

Finally, in this chapter, we will review the differences between authentication and authorization. Both concepts are very important and definitely impossible to put aside in the context of securities terms.

Chapter 3, Security Management with RESTEasy, shows how RESTEasy offers mechanisms to handle security, starting from a fairly basic model (coarse-grained) to a more elaborate one (fine-grained) in which you can perform more exhaustive controls, including managing not only configuration files, but also programmatical files.

Chapter 4, RESTEasy Skeleton Key, helps us study the OAuth implementation along with the token bearer implementation and Single Sign-On. All of them are used in order to limit the way the resources are shared. As always, you will get hands-on with code and real examples. We want to show you how sharing resources and information between applications through these technologies has turned into one of the most useful and powerful techniques by allowing clients or users to use their credentials only once to access several services, limiting the access to third-party applications to your information or data, and implementing access control through the token bearer. You will learn to apply these technologies and concepts in order to build secure and flexible applications.

Chapter 5, Digital Signatures and Encryption of Messages, helps us understand the benefits of digital signatures using a simple example; you'll notice how the message's receiver can validate the identity of the sender. In addition, we will simulate when an external agent modifies data in transit and see how digital signatures can help us to detect it, in order to avoid working with corrupted data.

Finally, we will explain SMIME for body encryption and how it works, with an example that encrypts requests and responses for your better understanding.