HotJava for Linux

#### "Linux Gazette...making Linux just a little less scary! "

# Running Sun's Hotjava Browser on a Linux System

#### by Larry Ayers

Copyright (c) 1996

##### Published in Issue 11 of the Linux Gazette

### Introduction

Recently I stopped by the Java-Linux web-page to see what was new and found an intriguing new link. This link took me to a page which contains a script allowing Sun Microsystem's HotJava web-browser to be run on a Linux machine. I was skeptical, as the Java-based browser supposedly is only available in versions for Win 95/NT and Sparc Solaris systems. The comments in the script stated that the Sparc version should be downloaded and installed, after which the new script should be edited to reflect the location of the Java Developers Kit on the machine. The comments were rather terse; what I wanted to know was whether it worked well enough to even bother with.

### Download and Installation

You've probably guessed that my curiosity got the better of me; feeling faintly foolish I FTP'ed the three-and-one-half megabytes of Sparc binaries from the Javasoft site and installed them. After substituting the new start-up shell script for the supplied script I was ready to try it out. The first try it died, complaining that it couldn't find mkdir in /usr/bin. I re-edited the shell script and corrected that path. This time it worked, and I have to say I was impressed.

### So What's It Like?

HotJava is a graphically well-designed browser. The graphics in the various help-pages, the buttons, and the general design are all professionally executed, and pleasing to the eye. Here is a screen-shot of one of the included monitor applets:

The browser takes about as long to start up as Netscape does. It's informative to start it from an xterm window, as verbose messages scroll by throughout the session indicating what threads and applets are active. You'll also be able to see its dying words, as (at least on my machine) it will only run for about one-half an hour before crashing. While it runs it seems to do well, though. I aimed it at http://www.gamelan.com and tried a variety of java applets. They seemed to take longer to load than with Netscape, but once loaded worked well. Frames, once a Netscape exclusive, are supported. There is also a menu option allowing hotlists from other browsers to be imported.

In its current "pre-beta" state HotJava uses an awful lot of memory. Top reported usage of fourteen to fifteen megabytes! No wonder I could only start it when the machine was lightly loaded. The current version of the Linux java compiler is a memory hog as well, so perhaps this is a trait of java, being an interpreted language as it is.

HotJava includes two interesting monitor applets. One shows the current memory usage in bar-graph form, with a button which will clear past images and pages from memory, rather like Netscape's "clear memory cache" function. The other shows a list of all of the active threads, with often as many as twenty to thirty active at once.

I did notice that if used locally; i.e. for viewing HTML files on the local hard disk rather than on the net, it wouldn't crash. GIF and JPEG images referred to from a page (rather than inline on the page) are viewed in the same window with an internal viewer. This is in contrast to some browsers which call an external program for this purpose.

I should state here that I don't have the Java Developer's Kit version 1.02 patchlevel 2 installed; my installation is the plain 1.02. Patchlevel 2 is recommended on the Java-Linux page. Perhaps some of the problems I had with HotJava can be attributed to my slightly out-of-date JDK.

### Conclusion

Even with all of the faults related above my overall impression was positive. Remember, this is a pre-beta release. HotJava is a major evolutionary step up from the web-page applets which are the most common uses of java these days. What other large application written in java is available? It is a tribute to the inherent cross-platform nature of the java language that a release intended for Sparc Solaris machines will run at all on my humble 486 Linux box. Thanks go to whomever modified the hotjava script and made it available on the Java-Linux site!

Last modified: Sat Oct 26 17:29:28 CDT 1996