# Introduction

![](/files/-M3y23qP_vBhwwIKmmMB)

> ### Head over to [Leanpub ](https://leanpub.com/rest-assured-with-jaxrs)to grab a PDF version of this book

Enterprise Java Beans (EJB) are one of the core components of the Java EE Platform and this book covers the latest version (3.2) of the EJB specification with a special emphasis on its annotations.

Think of it as an EJB cheat sheet or a quick reference. It consists of short chapters, each of which cover a specific part of the EJB specification. Here is a comprehensive list - life cycle management, dependency & resource injection, pooling, concurrency, web services, interceptors, security, transactions, schedulers & timers, asynchronous model, eager initialization (with Singletons) and exception handling.

> **Why focus on annotations ?**
>
> EJBs present a simplified, declarative and POJO based programming model powered by annotations. This is personified by its API layout which consists of 32 annotations. From a Java EE developer standpoint, the real magic of EJBs lies in its annotations !

The general outline of the book is simple and focused on the following

### Categorize EJB features

This helps the reader (especially beginners) see the big picture, makes the EJB landscape look less daunting and ensures that the learning curve is not as steep

### Map EJB features to appropriate annotations

As stated earlier, this book lays a lot of emphasis on EJB annotations. All the features/categories are explored from the point of view of their respective annotations. This provides a logical and intuitive way of understanding them in a contextual manner rather than in a sporadic/random fashion

## Is it for you ?

Both beginners and experienced developers can make use of this book. For folks new to Java EE (in general) and EJB (to be specific) can use it as a high level guide to get a feel of what EJB as a technology has to offer and to pick up its feature. Seasoned developers can use this as a quick reference/refrsher from time to time.

## Source code

The code for this book is available in [GitHub](https://github.com/abhirockzz/ejb-annotations-primer). It was developed using [NetBeans 8.1](https://netbeans.org/) which has out-of-the support for [Java EE 7](http://www.oracle.com/technetwork/java/javaee/tech/index.html) and comes bundled with [GlassFish 4.1.1](https://glassfish.java.net/)


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