Cellsprings Help: Known Problems

Cellsprings/DT

So far I've only had a chance to test Cellsprings on 5 desktop Java runtime environments (REs) for Win32 and Linux. Only a few minor RE-specific software errors have surfaced, but the performance differences are dramatic.

Sun JDK/JRE 1.1.8 (Win32)

This is the best of Sun's REs for running Cellsprings. The performance is very good and there's only one significant area of "irregularity" of which I'm aware:
  • Main menu glitches. The application window occasionally comes up with rearranged or missing main-menu items. If this happens, just exit and restart Cellsprings - I've never known it to happen twice in a row. I'd be interested in knowing how system-specific this behavior is - reports, positive or negative, are invited.

Sun JDK/JRE 1.2.2 (Win32)

It was an unpleasant surprise to discover that Cellsprings performance is abysmal under this RE - as in slow and jerky. Indeed, it is the worst environment in terms of performance of the seven REs presently installed on my computer (including browsers). I'm puzzled by this - it uses a Symantec JIT compiler, which one would think would be similar to the one 1.1.8 uses. Perhaps the optimizations are skewed toward big non-realtime business apps. Anyway, forget this one for running Cellsprings.

Sun JDK/JRE 1.3.0 (Win32)

Cellsprings exhibits better performance under this RE than under 1.2.2, but it's still a far cry from that provided by Sun's lean and mean 1.1.8 runtime. (The much-vaunted HotSpot VM doesn't seem so hot for realtime apps, but maybe I'm missing something.) This is also one of the three runtimes under which Cellsprings was seen to exhibit sporadic main menu irregularities (see the 1.1.8 entry for more info on that one). This RE also seems less stable than the other Sun environments tested.

IBM JDK/JRE 1.8.8 (Linux)

This is a fast RE, at least in the tested 8-bit color mode, but be sure to edit the user.props file to take full advantage. (See the user options section of the install notes.) The one problem observed is an often annoyingly severe "jerkiness" in CA update. (Running the VM with the -noclassgc option doesn't seem to help, BTW. Input from someone with a better clue on this RE is welcome.)

Blackdown JDK/JRE 1.8.8 v1 (Linux)

Again this was tested only in 8-bit color mode. Cellsprings ran a lot slower under this implementation as compared to IBM's, though editing the user.props file helped a bit. The only other problem noted was the fact that Frame windows, including the main window, come up with the title bar off the screen - but that might have something to do with my particular Linux GUI setup.

Cellsprings/Web

Most of the problems are specific to the Java runtime environments (REs) that shipped with particular browsers, so that's how I've broken them out.

Netscape Navigator/Communicator 4.xx (Win32)

This is generally a good browser for running Cellsprings, but it's important to realize that early members of the series shipped with a Java runtime that doesn't fully support JDK 1.1. See the compatibility notes for more info.
  • Browser causes an invalid page fault after you save a file to the server.
    On my system this happens when saving big movies and occasionally other files. It's probably system specific - DLLs and such. Leastwise that's what Netscape blames it on. Interestingly, the file saves properly to the server, but then the browser immediately crashes. Not good, but I know of no cure. So much for the Java sandbox.
  • Main menu glitches
    For unknown reasons, the applet's window will sometimes pop up with the main menu items out of whack - i.e., rearranged or omitted with random abandon. I'm under the impression this is more likely during a browser session in which the applet has already been running. Be that as it may, if you are bitten by this bug close the applet's popup window and try a simple reload of the applet's web page. If that doesn't work, restart Netscape itself. (Fortunately, Netscape caches both JARs by default, so it won't need to download them again when you reaccess the page after a browser restart.)

Microsoft Internet Explorer 5 (Win32)

In my testing under the RE that shipped with IE 5.01 in June 2000 the applet runs quite well indeed. (I don't yet have specific info on earlier or later versions.) The one problem of which I'm aware is itemized below.
  • Resource JAR downloads every time the applet initializes.
    For some reason IE5, unlike IE4 (my installation at least), apparently doesn't cache the resource JAR, even in memory. I know of no user work-around.

Microsoft Internet Explorer 4 (Win32)

I can only speak to the RE that shipped with version 4.01SP1 for Windows 95, but its AWT implementation was inferior to that of the above two browsers, as you can see below. It's not recommended for more than casual Java use, in light of the better options available.
  • Popup checkmenus either unavailable or faulty
    No doubt because of the funky implementation of checkable menu items (which makes no sense to me - can't they program their own OS?), such items appear not to be properly supported on popup menus (as opposed to the main menu). Thus three of my handy-dandy tool buttons do not work as intended. Their functions are mirrored on the main menu, and if the applet detects the offending Java version it overrides the buttons with a message saying as much. But this detection only detects the offender I know about, and it's likely there are others. If you get a popup menu that doesn't correctly track your selections, you'll know you have one of them.
  • No Copy/Paste Between Java and OS
    Most AWT implementations for Windows support Ctrl-C copy of TextComponent contents, and Ctrl-V paste into editable TextComponents - but this ain't one of 'em. The worst thing about this is that it renders the Import functions in the RuleTool - especially for General 2Bit rules - comparatively useless.
  • Inferior Performance
    At least for Cellsprings purposes, this implementation is comparatively sluggish.

Netscape Navigator/Communicator 4 (Linux)

I didn't bother to test this browser much, owing to its sorry performance. This is yet another example of the huge disparity in Netscape's Java implementations from platform to platform (the Mac case being the most notorious). Leastwise, the Win32 equivalent runs rings around Netscape 4.5 for Linux, installed on the same computer. Unless there's a Linux browser (or plug-in) out there with better Java capabilities, Linux users are advised to download the desktop version of Cellsprings.

Mac OS Runtime for Java (MRJ) ver. 2.2

The applet is reported to work well in this environment, with no out-and-out bugs yet identified. However, there are a couple of other problems which I hope will be addressed in future versions.
  • No Copy/Paste Between Java and OS
    From the reports I've received, this appears to be another AWT implementation that doesn't support copy-to and paste-from the system clipboard. Unfortunately, AFAIK there are no other JDK 1.1 compatible environments on the Mac.
  • Inferior Performance
    Though much improved, this runtime reportedly still lags well behind current versions on other platforms. Anyone know whether it uses a JIT compiler?

Copyright © 1998-2000 J. M. G. Elliott.