Strange Java Issue


See below for the solution. Spoiler – It’s a typo.

Back in April 2020, I wrote a little program to run a sequence of LibreOffice Impress Slide shows. For ease of deployment on Windows and Linux, I built the program in Java. And it worked just fine. Here’s what the program looks like:

You can follow the whole Saga of its development using this link. The program has been working very well on Linux Mint 19 and 20 and Windows 10 for a couple of months now. I’ve not changed anything since May 16. Here’s the github repository.

It’s Not Working On One System

After upgrading my various systems to Linux Mint 20 over the past week or so, I tested this among other programs and all was well. However, the Impress Show Runner fails on one of the systems. It fails in a strange way. All of the features work, but it fails to launch the Impress program. If you type the impress program line that the program uses into a terminal, it works fine. So libreoffice impress is there and works fine. Here is the system where it fails:

System where the program fails

Here’s a virtual machine where the program works on Linux Mint 20.

Works fine on this Linux Mint 20 system running in a VM.

Just to be clear. I’m pretty sure that being in a Virtual Machine or not has nothing to do with the issue. And the problem is not that the program does not run and do everything else correctly. It just fails to LAUNCH Impress.

On both systems, the program is launched from a shortcut on the desktop, and the jar file is marked Executable.

I’m at a complete loss to figure out what’s going on. Anybody have any suggestions? Any more information you need.

Java Console Output

Normally when you run this application, the console output is discarded. I wanted to see if there was any console output. So after lots of googling, which found no answers, I found that the openjdk will run a jar file, and the console output will go to the terminal window. I renamed a copy of the jar file to “isr.jar” to make the typing easier.

So I tried the console commands to run an impress slide show in the terminal window: First just to launch impress with the slide show. And then to actually show the command, in a window.

Oh! Wait! You dummy!

If we look closely at the command line options in the java program, I have miss-typed the SHOW option.

---SHOW rather than --SHOW

You dummy. It is fine now. I’m a little surprised that there is no error returned from the program, but I am not capturing the output from Impress and writing it to the java console. Oh well. Problem solved.

Since the java program is designed to run on Windows 10, or any Linux, I need to have a way to input the actually command to run Libreoffice Impress to show a slideshow. And that means that I can have typeos.

Check your typing.