Introduction

This article investigates the viability of doing J2EE development using software that is available for free.

In order to investigate the options, very popular packages are chosen, and used to develop a simple J2EE application.

A review of the hardware necessary is beyond the scope of this article. Passing reference is made to hardware configurations used, but they are not to be taken as recommended.

Software Components

Developing enterprise applications requires software, below is a list of the software used.

• An operating system: Suse Linux 9.1 and Windows XP
• A database management system (DBMS): MySQL version 5.0.18
• An application server: JBoss version 4.0.4 RC1
• Integrated development environment(s) (IDE): Eclipse version 3.1.1
• Java Virtual Machine (JVM): Sun Microsystems JDK version 1.5.0_06

For development, Suse Linux is used. It is possible to use an other Linux distribution, or an other operating system. Below is a list of some of the operating systems that can be used:

• Linux
• Microsoft Windows (post Windows Me releases)
• MAC OSX
• Solaris
• AIX
• HP-UX

And many others: so long as the operating system can run the Database, the IDE and the Java Virtual Machine, the operating system should be sufficient for development purposes.

The network used does contain some computers which run Microsoft Windows. These PC's can access the Linux machine using a program called XWinLogon. This allows the Linux XWindows desktop to appear within a window on the Microsoft PC. More information on XWinLogon is available here.

The database used is MySQL. It can be downloaded from www.mysql.com

MySQL is available for free, and is widely regarded as a fast, multi-user, robust database server.

In this article, the tables are created using raw sql, this ensures that the reader can cut and paste the sql necessary to create the database objects used in this article.

In the end, creating MySQL databases using SQL scripts is probably a good idea anyway: it means we can refer to the scripts and so recreate the database structure on another machine, very easily.

The application server used is JBoss. JBoss can be downloaded from www.jboss.org

JBoss is written in Java, and can therefore run on an operating system which supports the JVM (Java Virtual Machine).

Integrated Development Environment

IDE's are very useful for software developers. Most of the tasks involved can be done using a simple text editor, and command line tools. IDE's make the process much easier by replacing cryptic commands with mouse clicks.

Code editors usually have syntax highlighting, which makes the code much more readable. Easy navigation to the Java API reference documents is usually also present in IDE's.

IDE's allow the code to be compiled, deployed and debugged at the click of a mouse. When working with J2EE servers, this may require some initial configuration, but is well worth the effort.

The IDE chosen is Eclipse, which can be downloaded from www.eclipse.org.

Eclipse is written in Java, and can therefore run on an operating system which supports the JVM (Java Virtual Machine).

Eclipse uses graphical widgets developed by IBM. So the graphical interface is not done using SWING (Java's graphical interface widgets), Eclipse uses the widget library called SWT. SWT is bundled with the Eclipse download, so there is no extra effort needed to download, install and use Eclipse.

Last, but not least, the Java Virtual Machine (JVM) allows our enterprise application, application server and IDE, to run. Sun provides JVM's for Linux, Solaris and Windows operating systems. Other Operating System vendors provide JVM's to support their own platforms.

The Java SDK is downloaded from java.sun.com. It is important to note that the JDK is downloaded, the JRE (Java Runtime Environment) should not be downloaded. The JRE does not contain the compiler, which Eclipse and JBoss require.

The documentation bundle is also worth downloading, as it contains the the Java API's documentation.

Next: Installing The Software