Java Application Development on Linux

Softcover

ISBN 10: 013143697X ISBN 13: 9780131436978

Publisher: Prentice Hall, 2004

Linux is the fastest-growing Java development platform because it saves money and time by serving as a platform for both development and deployment. But developers face significant platform-specific challenges when managing and deploying Java applications in a controlled production environment.

Written for Java and Linux developers alike, Java™ Application Development on Linux® is the hands-on guide to the full Java application development lifecycle on Linux.

Determined to spare other developers hours of trial and error, Albing and Schwarz demonstrate the platform, tools, and application development by showing realistic, easy-to-follow examples. After a simple command-line application introduces basic tools, this program leads readers through business-logic object analysis, database design, Java servlet UIs, Java Server Pages (JSP) UIs, Swing GUIs, and Standard Widget Toolkit (SWT) GUIs. Scaling up to the enterprise level provides the opportunity to use both the JBoss Application Server and the Apache Geronimo Application Servers, and Enterprise JavaBeans (EJB).

Readers learn how to

• Use development tools available on Linux, such as the GNU Compiler for Java (gcj), Ant, the NetBeans IDE, IBM's Eclipse Java IDE, JUnit, and SunONE Studio

• Develop business logic layers using Java DataBase Connectivity (JDBC)

• Add a Web interface using servlets and JSPs

• Add a GUI using Sun's Abstract Window Toolkit (AWT) and IBM's SWT

• Deploy EJBs in Linux

The authors conclude by demonstrating how a hierarchy of budgets can be created, tracked, and shared with Concurrent Versions System (CVS).

A companion Website includes all source code and a link to each tool described.

Java™ Application Development on Linux® can propel you from a standing start to the full-speed development and deployment of Java applications on Linux.

About the Author:

Carl Albing is a programmer/analyst and consultant. With more than 20 years of industry experience, he has for several years been building business solutions using Linux and Java technologies. He has made technical presentations for conferences and corporations throughout the U.S., Canada, and Europe.

Michael Schwarz is a software engineer who has worked on Linux since its emergence. He is a frequent contributor to Linux Journal and the lead author of Multitool Linux (Addison-Wesley, 2002).

Excerpt. © Reprinted by permission. All rights reserved.:

Java and Linux

Why another book on Java? Why a book on Java and Linux? Isn't Java a platform-independent system? Aren't there enough books on Java? Can't I learn everything I need to know from the Web?

No doubt, there are a host of Java books on the market. We didn't wake up one morning and say, "You know what the world really needs? Another book about Java!" No. What we realized was that there are a couple of "holes" in the Java book market.

First, Linux as a development platform and deployment platform for Java applications has been largely ignored. This is despite the fact that the *nixplatform (meaning all UNIX and UNIX-like systems, Linux included) has long been recognized as one of the most programmer-friendly platforms in existence. Those few resources for Java on Linux that exist emphasize tools to the exclusion of the Java language and APIs.

Second, books on the Java language and APIs have focused on pedagogical examples that serve to illustrate the details of the language and its libraries, but very few of these examples are in themselves practically useful, and they tend to deal only with the issues of writing programs, and not at all with deploying and maintaining them. Anyone who has worked on a major software project, especially a software project that is developed and deployed in a business for a business, knows that designing and coding are only about half of the work involved. Yes, writing Java code is only slightly affected by the development and the deployment platform, but the process of releasing and maintaining such applications is significantly different between platforms.

To address these missing pieces, we decided to cover development and deployment of a Java application that has command-line, GUI, servlet, and enterprise components on a Linux platform. We're writing the guide book we wish we had had when we started writing and deploying Java applications on Linux. We're going to show you a simplistic enterprise application, "from cradle to grave," but along the way cover issues of design process, production environment, setup, administration, and maintenance that few books bother to cover.

If you are considering buying this book and you are wondering if there is any information in here that you can't get for free on the Web, then, no. There is not. In fact, there is little information in any Java or Linux book that is not available for free on the Internet. In fact, in each of our chapters we will tell you where on the Web to find virtually all of the information we present, and then some. And yet books continue to sell, and we have the chutzpah to ask you to buy the book. The reason is that Web information is scattered, unorganized, and of highly variable quality. We will be trying to bring all the relevant information together in this book, in a clearly organized manner (and, we would like to believe, at an acceptably high level of quality). We think that has value.

Also, this book is part of the Bruce Perens' Open Source Series. This book is part of the Web literature. And you may freely read it and use it on the Web. We hope this book will be one of those you use on the Web and buy on paper. We don't know about you, but we like to use Web books for reference, but for reading, we like books. We own at least three books that are available for free on the Web: Thinking in C++, Thinking in Java, and O'Reilly's Docbook: The Definitive Guide. We hope that open publishing will be the new model.

This is not to say this book is without purely pedagogical examples. Especially in Part I we make use of your typical "throwaway" examples and single classes. To try to illustrate the basics with a complete application would obscure and confuse the points being illustrated.

Free Software and Java

GNU/Linux is Free Software. It is Open Source. I don't even want to start the debate on what each term means and which one is "right." One of the two authors of this book is a Free Software advocate, and the other is of a purely laissez-faire attitude towards the question (we won't tell you which, although we invite you to guess). But even with a deliberate decision to cease fire, the question remains: Is Java Open Source or Free Software?

The answer is mixed. Neither Sun's nor IBM's Java implementations are Open Source or Free Software. You may download and use them for free, but you do not have the source code to them, nor do you have the right to make modifications to them. This book will cover the GNU Compiler for Java, which compiles Java source code to native machine code. The GNU Compiler for Java (gcj) is both Open Source and Free Software. It is, however, supporting differing levels of the Java APIs (some packages are current, some are back at 1.1.x levels) and does not fully support the AWT or Swing GUIs.

However, none of this means that you cannot write your own Java programs and release them under a Free Software or Open Source license. So you can certainly develop Free Software in Java. Staunch Free Software partisans (such as Richard Stallman and the Free Software Foundation) would question the wisdom of doing so. Their argument would be that a Free Software product that depends on non-Free tools isn't really Free Software, since to compile, use, or modify it, you need to make use of a proprietary tool.

There is more than one effort to produce a Free Software Java runtime implementation. None of them is "ready for prime time." It would, in our opinion, be a very good thing for Sun to release their SDK and Java Virtual Machine as Free Software. But so far, they have steadily resisted calls to do so.

The fact, however, that two distinct vendors (Sun and IBM) produce effectively interchangeable development and runtime environments reduces some of the risk that you face when you select a platform available only from a single vendor who does not provide source code.

So, to put the case firmly: Java is free for use, but it is certainly not Free Software as defined in The GNU Manifesto (www.gnu.org/gnu/manifesto.html) or the GNU General Public License (www.gnu.org/copyleft/gpl.html). This is a political and philosophical issue of interest only to those aforementioned Free Software partisans. For the rest of us, this has no bearing on Java's technical or business merits. As for us, obviously we like the language or we wouldn't be writing about it.

You Can Help!

This book is part of the Bruce Perens' Open Source Series. Shortly after this book is published in dead-tree form, it will be on the Web (www.javalinuxbook.com/), free for use, redistribution, and modification in compliance with the terms of the Open Publication License (www.opencontent.org/openpub/), with no options taken. You can immediately create your own version as permitted in that license.

Naturally enough, we plan to maintain our "official" version of the online book, so we encourage you to send suggestions, corrections, extensions, comments, and ideas to us. Please send any such to javalinux@multitool.net and we will try to keep our little tome up-to-date so it continues to serve the needs of the Java and Linux development communities.

Acknowledgments

First off, we naturally wish to thank Mark L. Taub, our acquisitions editor at Prentice Hall PTR, for believing in the book and in open publishing as the way to put it out there. We also want to thank Bruce Perens for lending his name and powers of persuasion to open-content publishing through the Bruce Peren's Open Source Series. Thanks, too, to Patrick Cash-Peterson and Tyrrell Albaugh, who worked as our in-house production contacts, for all the behind-the-scenes work they did, including overseeing the cover.

In more direct terms of content, we owe major thanks to Kirk Vogen of IBM Consulting in Minneapolis for his article on using SWT with gcj, and for his kind help in allowing us to use the ideas he first presented in his IBM developerWorks articles; and to Deepak Kumar for graciously allowing us to base our build .xml file for EJBs off of a version that he wrote.

Thanks, too, to Andrew Albing for his help in drawing some of our diagrams,and to George Logajan and to Andy Miller for sharing their insights onthe more intricate details of Swing.

We also wish to express our great indebtedness to our technical reviewers, especially Andrew Hayes, Steve Huseth, and Dan Moore. A very large thank youis also due to Alina Kirsanova whose eye for detail, endless patience, and tenacity, and overall talent with proofng, layout, and more added so much refinement and improvement to the book. We are grateful for all their contributions. Any errors or omissions in this text are our fault and certainly not theirs. The book is much stronger for all their efforts.

There are likely many more people we ought to thank, especially those at Prentice Hall PTR, whose names and contributions we may never know, but we do know that this was an effort of many more people than just the authors, and we are grateful to them all.