Norman Richards

The Austin Java User Group recently sponsored a contest to create the smallest Java Hello World! program. The rules were simple: create the smallest Java class that when executed will display the text "Hello World!" (and only that text) to the console. The restrictions were that the class must execute under Sun's 1.3 JRE. It may make use of any class or file distributed with the JRE, but any additional files (excluding arguments on the command line) count against the byte total of the Java class file. In this article, I explain how I arrived at my 70-byte solution. I hope that in the process you learn a bit about Java class files and the Java Virtual Machine. I also urge you to take the challenge before viewing my solution. Getting Started Let's first look at the canonical Java Hello World! program. public class Hello { public static void main(String[] args) { System.... (more)

Dynamic Code Generation

Java is often criticized for its performance, particularly in comparison to equivalent code written in languages such as C and C++. Advances in runtime performance have silenced many critics, but still there are times when no matter how fast Java is, it's just not fast enough. Fortunately, Java does have some unique properties that make a class of optimizations accessible that are not easily applied to other platforms. One technique that can be used to great effect on certain types of tasks is dynamic code generation. Dynamic code generation is the process of generating Java clas... (more)

Manifest Destiny

Releasing Java applications can be a real challenge. Fortunately, Java provides a rich set of features for packaging and deploying applications that can simplify the release process significantly. This article presents some of the issues involved with packaging Java code. I'll explore the Java manifest file and suggest ways it can be used to manage JAR file dependencies and to eliminate classpath issues normally associated with cross-platform deployment. I'll also explain how to use the package-versioning features of the manifest to ensure the compatibility of packages used. Wh... (more)

Seam: The Next Step in the Evolution of Web Applications

Web sites were originally static. Later dynamic content came about through CGI scripts paving the way for the first true Web applications. Since HTTP was entirely stateless, it became necessary to invent ways for requests to be linked together in a sequence. At first state was added to the URLs, but later the cookie concept came into being. By giving each user a special token, the server could maintain a context for each user, the HTTP session where the application can store state. As simple as it is, the HTTP session defines the entire concept of what a Web application is today.... (more)

My impressions of the "Java" Desktop System demo

Sun gave a demo of their new Java Desktop System at last week's AustinJUG meeting. Of course, the "Java" Desktop has absolutely nothing to do with Java. I see it as an admission by Sun that the Sun brand is dead. Nobody wants to buy Sun hardware or software anymore. But, the Java brand still has some value. My biggest fear in all of this is that instead of letting Java pull Sun up, Sun has insured that the Java brand is going down with the Sun ship. Let's all hope that Sun's fortunes turn. An interesting point is that the Java Desktop System runs only on x86 hardware and not on ... (more)