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

Mapping inheritance


There are times when it will be very useful for entities to inherit from each others. Suppose, for example, that two entities Actor and Director exist, and each has a set of common attributes (name and birth date), but each has other specific attributes. It's very natural to create a Person superclass for them, putting inside it all the common attributes, then make both theActorandDirectorinherit from it.

The question is, if we have used the mentioned design, how will our entities be mapped to the database ? In JPA, there are three inheritance strategies that can be used to achieve inheritance mapping:

  • Single table strategy
  • Joined table strategy
  • Table per class strategy

In the following sections, we are going to look at each strategy in detail.

Single table strategy

In the single table strategy, only one table will be used to represent all entities in the inheritance relationship. All common attributes, as well as the specific attributes, will be used as columns in one table...