Java EE At A Glance

Java EE (Java Platform, Enterprise Edition) is a platform for server programming using Java programming language. Initially the platform was known as J2EE (Java 2 Platform, Enterprise Edition) and was later known as Java EE. The latest version is known as Java EE 6. The new features of Java EE make it even more adaptable and make it easy to outsource Java development, for example. Java EE APIs includes JDBC, RMI, email, JMS, Web services, XML among others. Features unique to Jave EE are Enterprise JavaBeans, Connectors, servlets, portlets, JavaServer Pages, etc., allowing portability and scalability of enterprise applications and also work with legacy systems enabling offshore Java development.

Overview

Java EE allows developers to develop large, reliable, scalable and secure applications known as enterprise applications.These applications are used by large corporations to solve their IT problems. Increasingly, Java EE is also useful for individual developers and small organizations in this increasingly networked world where the norm is to outsource Java development. All these make Java EE complex. To simplify the enterprise application development, Java EE comes with clearly demarcated functional segments like development model, API, and run-time environment otherwise called as multi-tiered where on every tier the developer concentrates on its own functionality. This modularity in approach helps to harness the full potential to offshore Java development.

Tiered applications

The application is split into multi-tiers depending on the functionality: a client tier, middle tier, and data tier. Development in particular tiers can be outsourced enabling a flexible approach to outsource Java development.

• Client tier: the client tier consists of an application like a Web browser, stand-alone application, or other servers running on a different machine from the Java EE server, which makes a request to the Java EE server. The server receives the request, processes it, and returns a response back to the requesting application.


• Middle tier: the middle tier contains business functions that handle client requests and process application data. The components of the middle tier impart the business logic needed for an application. Business logic provides functionality to a particular business domain, e.g., financial industry, e-commerce. This tier contains the core functionality.


• Data tier: the data tier is also known as enterprise information systems. It contains enterprise resource planning systems, database servers and systems and a couple of legacy data sources. These data resources are typically stored in a system separate from the Java EE server.

Java EE servers

Java EE server helps in executing the APIs belonging to Java EE platform and provides Java EE services. It is called as application server since it serves application data to clients, similar to a Web server that serves Web pages to Web browsers. The Java EE server provides services to various component types in the form of containers. To offshore Java development, a containerized architecture provides immense flexibility. The different containers are described below.

• Java EE containers: these provide the interface between the lower-level functionality and the component and help in supporting the component.


• Web container: it provides an interface between web server and the web components.


• Application-side client container: it provides an interface between Java EE application clients and the Java EE server.


• EJB container: it provides an interface between enterprise beans and the Java EE server.

Requirements for Java EE

To get started on Java EE development, programmers should install and configure their system ecosystem as given in the checklist below.

• Get Java EE 6 SDK


• Get NetBeans IDE and all necessary plugins


• Configure the environment