Book Image

Developing Middleware in Java EE 8

Book Image

Developing Middleware in Java EE 8

Overview of this book

Middleware is the infrastructure in software based applications that enables businesses to solve problems, operate more efficiently, and make money. As the use of middleware extends beyond a single application, the importance of having it written by experts increases substantially. This book will help you become an expert in developing middleware for a variety of applications. The book starts off by exploring the latest Java EE 8 APIs with newer features and managing dependencies with CDI 2.0. You will learn to implement object-to-relational mapping using JPA 2.1 and validate data using bean validation. You will also work with different types of EJB to develop business logic, and with design RESTful APIs by utilizing different HTTP methods and activating JAX-RS features in enterprise applications. You will learn to secure your middleware with Java Security 1.0 and implement various authentication techniques, such as OAuth authentication. In the concluding chapters, you will use various test technologies, such as JUnit and Mockito, to test applications, and Docker to deploy your enterprise applications. By the end of the book, you will be proficient in developing robust, effective, and distributed middleware for your business.
Table of Contents (18 chapters)
Title Page
Copyright and Credits
Dedication
Packt Upsell
Contributors
Preface
Index

Understanding WebSockets 


In the early years of the web, the classic request-response model of HTTP communication put a bottleneck limitation on any application that required the server to send updates directly to the client. To overcome this limitation, the WebSockets protocol was invented.

WebSockets is a TCP protocol that was invented to allow web browsers to open interactive communication sessions with web servers. Unlike HTTP, WebSockets is not based on the request-response communication model. Instead, it opens a full-duplex communication channel with the server, allowing both server and client to exchange messages in real time. This makes it easier to build more creative web apps such as chat, online gaming, real-time statistics, and much more.

Although WebSockets is totally different from HTTP, it's designed specifically to work over the HTTP protocol. Clients perform web-socket connections by handshaking a web server using the HTTP upgrade header, which is the topic of the following...