Java Reference
In-Depth Information
Chapter 1. Overview
Developers today increasingly recognize the need for distributed, transactional, and port-
able applications that leverage the speed, security, and reliability of server-side technology.
Enterprise applications
provide the business logic for an enterprise. They are centrally
managed and often interact with other enterprise software. In the world of information tech-
nology, enterprise applications must be designed, built, and produced for less money, with
greater speed, and with fewer resources.
With the Java Platform, Enterprise Edition (Java EE), development of Java enterprise ap-
plications has never been easier or faster. The aim of the Java EE platform is to provide
developers with a powerful set of APIs while shortening development time, reducing ap-
plication complexity, and improving application performance.
The Java EE platform is developed through the Java Community Process (JCP), which is
responsible for all Java technologies. Expert groups, composed of interested parties, have
created Java Specification Requests (JSRs) to define the various Java EE technologies. The
work of the Java Community under the JCP program helps to ensure Java technology's
standard of stability and cross-platform compatibility.
The Java EE platform uses a simplified programming model. XML deployment descriptors
are optional. Instead, a developer can simply enter the information as an
annotation
directly
into a Java source file, and the Java EE server will configure the component at deployment
and runtime. These annotations are generally used to embed in a program data that would
otherwise be furnished in a deployment descriptor. With annotations, you put the specific-
ation information in your code next to the program element affected.
In the Java EE platform, dependency injection can be applied to all resources a component
needs, effectively hiding the creation and lookup of resources from application code.
Dependency injection can be used in EJB containers, web containers, and application cli-
ents. Dependency injection allows the Java EE container to automatically insert references
to other required components or resources, using annotations.
This tutorial uses examples to describe the features available in the Java EE platform for
developing enterprise applications. Whether you are a new or experienced Enterprise de-
veloper, you should find the examples and accompanying text a valuable and accessible
knowledge base for creating your own solutions.
If you are new to Java EE enterprise application development, this chapter is a good place
to start. Here you will review development basics, learn about the Java EE architecture and
APIs, become acquainted with important terms and concepts, and find out how to approach
Java EE application programming, assembly, and deployment.