I far prefer Project Builder for Java development in general, but there's no doubt that Forte is useful and powerful, especially if you need to use a Swing interface. And, unlike JBuilder, it's free. It's also unsupported on Mac OS X, and to the casual developer attempting to download and install it, numerous and irritating hurdles present themselves. However, all the problems are solvable, and the last piece of the puzzle has fallen into place just today. So for anyone who is interested, here is how to get Forte working - without having to go through the command line or XWindows or anything - on Mac OS X. It Worked For Me™.
Step 1 - Getting Forte
Download "Sun One Studio 4.0 Community Edition" (Forte 4.0, in other words) from <a href="http://wwws.sun.com/software/sundev/jde/buy/index.html" target="_blank">http://wwws.sun.com/software/sundev/jde/buy/index.html</a>
Step 2 - Installing Forte
While the jar file that you download works fine if you double-click it and starts the installer, it will fail to find a suitable Java home because Mac OS X Java uses a non-standard directory structure. To fool the installer into working, create the "/Library/Java/Home/jre" and "/Library/Java/Home/jre/bin" directoryies. /Library/Java/Home should already exist, or there's something drastically wrong with your system. Installing Forte should now go without a hitch.
Step 3 - Running Forte
You can do this from the command line, but that is tedious and, even if you use a .command file, requires you to leave a Terminal window open while Forte is running. The workaround for this is to use an Applescript application to start Forte. Open Script Editor and create an script with just the following line of text:
</font><blockquote><font size="1" face="Geneva, Verdana, Arial, sans-serif">code:</font><hr /><pre style="font-size:x-small; font-family: monospace;">do shell script "/Applications/forte4j/bin/runide.sh -ui com.apple.mrj.swing.MacLookAndFeel -fontsize 10</pre><hr /></blockquote><font size="1" face="Geneva, Verdana, Arial, sans-serif">Call it "Forte" or something, save it as an application, and put it wherever you want. Note: This assumes that you have installed Forte in /Applications/forte4j; if this is not the case, change the script accordingly.
Step 4 - Configuring External Web Browser
This has been the sticking point for a while now; Forte uses web pages extensively, both internally and externally. It has its own (awful) Swing browser, but the two external browser options - External (UNIX) and External (Command Line) - would not work on OS X. At least, not out of the box. John Windberg has created a workaround that will allow you to use any external browser - even respecting your system settings! For the full details, go to <a href="http://forte.sun.com/ffj/articles/macOSX.html" target="_blank">http://forte.sun.com/ffj/articles/macOSX.html</a>
However! Unfortunately, the script given in that article is ever-so-slightly incorrect, and will fail to work, causing frustration and possibly exploding of heads. To fix it, simply replace the line </font><blockquote><font size="1" face="Geneva, Verdana, Arial, sans-serif">code:</font><hr /><pre style="font-size:x-small; font-family: monospace;">#!/bin/tcsh</pre><hr /></blockquote><font size="1" face="Geneva, Verdana, Arial, sans-serif">with </font><blockquote><font size="1" face="Geneva, Verdana, Arial, sans-serif">code:</font><hr /><pre style="font-size:x-small; font-family: monospace;">#!/bin/sh</pre><hr /></blockquote><font size="1" face="Geneva, Verdana, Arial, sans-serif">. The reason for this is that tcsh does not recognise variables in the same way as sh, so $1 will contain nothing whatsoever. Opening an empty URL is not very useful.
That's about it! You now have a double-clickable Forte which integrates with your system (and, indeed, installs in the first place). I hope that someone finds this useful, and if you have any further questions, feel free to post them.