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presentations: Cross-Browser Java


	Presentations by eXtropia CTO Gunther Birznieks

Making Java Applets Work On All Web Browsers

This is a talk outlining techniques for making Java Applets that work well in both Netscape and IE and across platforms of Windows, Mac and UNIX.

The two flaws that seem to most pervade the consciousness of would-be Java programmers is that Java doesn't have performance and that Java has not stood the test of "Write Once, Run Anywhere" motto.

First presented at Web Design and Development in Boston and San Francisco in 1998.

Zipped Powerpoint (29K) | PDF (72K)

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	Introduction

The two flaws that seem to most pervade the consciousness of would-be Java programmers is that Java doesn't have performance and that Java has not stood the test of "Write Once, Run Anywhere" motto.

Performance has been getting better. At the same time Java virtual machines are getting embedded in a lot more OSes and Browsers. Unfortunately, this means that there are a lot of differences in how they were implemented and the bugs they pose.

Worse, not everyone in the browser community upgrades right away. The likelihood is still high that when someone visits your site, they may still be using Internet Explorer or Netscape Navigator 3.x instead of the 4.x version. For an estimate of browser percentages, try looking at www.browserwatch.com.

It almost seems like a daunting and impossible task to write a decent Java applet that works on all these platforms. And to get information on the differences between browsers can be equally frustrating.

JavaSoft only really tracks bugs general to the JDK. It does not track Netscape or IE bugs. Not all IE or Netscape bugs get reported in their "official" databases. Other members of the Java Community have written snippets about various bugs and cross browser behavior, but usually only covering a single topic.

It is the goal of this site to focus on bringing all these "Cross Browser" sites together. Instead of just bringing bugs to light, this site also focuses on providing workarounds and sample source code to show how to get around these problems.

It is the intent of this site to provide knowledge about Cross Browser bugs and differences and more importantly, to provide a positive influence and encourage people to use Java in browsers by providing workarounds for those same issues.

Minimizing Cross Browser Differences Through Software Engineering (Coming Soon)
General Cross Platform Guidelines (Coming Soon)
Checking Your Java Platform
Using Inner Classes On JDK 1.0 Browsers
Making all JARs, ZIPs, and CAB archive formats load correctly using a single <APPLET> tag

Cross Browser Bugs And Workarounds

AWT-Related Bugs

Network, Threading, Class Library Bugs

Other Cross Browser Related Links

Elliotte Rusty Harold's comp.lang.java FAQ. Contains a page or so of good advice when writing cross browser applets.

Peter van der Linden's Java FAQ contains a lot of interesting cross platform/cross browser information such as dealing with Fonts and peer component limitations.

Core Web Programming by Marty Hall is one of the few books on Java that cover cross platform/cross browser issues.

Java AWT Reference by John Zukowski contains an appendix on cross browser and cross platform issues in general such as the ability of widgets to respond to events dealing with focus. Platform Specific Event Handling is on-line at the O'Reilly Site.
Write Once, Run...Where? By Mark Sienkiewicz is an excellent article in the USENIX Journal about the specific pitfalls on cross browser Java. He is one of the primary authors of the Java interface to Network Flight Recorder at www.nfr.net.

Wayne's list of Java Buglets & Demos. Mostly graphical in nature.

Java Plug-In from JavaSoft. Allows browsers to be compliant with the latest released JDK using a combination of alternate tags (OBJECT) and JavaScript in place of the APPLET tag.

Apple's MRJ (Mac Runtime Java) Kit/Developer Page. They support JavaSoft's new plug-in architecture and currently provide a similar solution to replacing the JDK built into Internet Explorer for Mac.

Java's SWING -- An alternative to the "heavyweight" peer GUI in AWT.

Digital Espresso is a WebZine Devoted To Java News. It includes a lot of interesting news on Java bugs that crop up.

Java- AWT: Is it really cross-platform? Dave Schultz did an excellent job at writing a Java program that tests the components on the AWT and ran them on various platforms to test their behavior. His results are documented here.

Java (TM) Applet User Interface Depends on the Browser From WDVL. This link shows how an applet can look very different on multiple browsers even on the same platform (Windows)!

Write Once. Run Anywhere? by Jason W. Purdy. He writes about some of the common AWT Bugs in applets within the scope of this article on cross browser differences.

Write Once, Run Anywhere-- How Real? -- This is an article from JavaSoft about the issue of browser/server compatibility in Java. BIAS ALERT: It seems HEAVILY geared towards painting a rosy picture for Java.

Java Tip 8: Threads, Netscape, and the resize problem By John Mitchell (submitted by Noah Green) talks about a bug in Netscape where resizing prematurely calls the stop() and start() methods. It also talks about workarounds

AWT: Java's Achilles Heel By Dave Dyer talks about the AWT problems in Javology (A good Java WebZine)

Java Woman's Java Bugs Page -- This is part of a larger web site on Java Information. An excellent resource!

Netscape 3.0+ Java Bugs List maintained by Jeff Harrington. This site is an interesting source of information. Unfortunately because it is kind of all put together as one huge list with no real format consistency it is hard to read. However, like the effort involved in eating crabs, this page yields some interesting tidbits of information when you get down to it.

Page that discusses some random IE and Netscape Bugs

Browser Bugs hard to catch in Net rush is an article about the state of competition in the browser industry and how it affects browser platform stability.

What is Java 'compliant' by Joe Weber is another Javology article about the state of different Java virtual machines.

Endangered List: Client Side Java By Richard Karpinski and Ellis Booker.

JPAL Anomalies -- This is a beginning attempt at coming up with a "Java Platform Abstraction Layer" for testing JVMs. It discusses a couple graphics related AWT bugs.

Writing Compatible Programs. This article from JavaSoft (Kathy Walrath) talks about how to mix JDK 1.1 and JDK 1.0.2 code in the same applet and switch depending on the browsers capabilities.

There are many sources that have contributed to this site. Generally, if someone submits a bug or workaround to me, your name will go under the references/acknowledgements section for that bug.

The people who have contributed most directly to my efforts here are Peter Chines, Anthony Masiello, Joseph Ryan, Mark McDonald, Erik Ferlanti, and Selena Sol.