I received narrated lectures from a colleague in a .jar format. These files were downloaded from Blackboard, but we have recently moved our entire system to Canvas. I am unfamiliar with this file type, but was able to download this player from Google, which allows me to play the files. I would prefer to either embed these videos into Canvas or convert them into a more common file type (e.g. ".mov", ".mp4" or something like that) so that my students have an easier time opening the files.
Any advice is greatly appreciated! I've attached a copy of one of the lecture files if it helps.
I do not see .jar listed as a supported file type for Canvas. Learn more at What types of files can be previewed in Canvas?
Does your player offer the opportunity to save-as a different file type? If not, here is a link to 31 Free Video Converter Programs that you might find useful.
A .jar file is a Java Archive and it can be opened using a problem like 7zip for Windows (Mac also has file archivers, but I don't have a recommendation there). Java support for the browsers has mostly been removed, so people would need to save it and then open it with Java from their computer's browser (not the web browser). You might be able to cobble something together that would open a Java Web Start, but it doesn't open a .jar file directly.
The use of Java is already one hurdle towards using this. It's what's inside that is more important. This one comes from Impatica. I'm not familiar with them, but their website touts "Build Once. Deliver Everywhere." It says that it uses HTML5 where possible and drops back to Flash when it can't. However, the files inside of this are dated 2005 so they are not HTML5, but most likely Flash. Impatica was described as a PowerPoint to Flash converter and it did so in a proprietary .imp file. For what it's worth, Adobe has announced end of life for Flash as well.
If you need to convert them so the students can use them, you may need to play them through the Java player and then capture them to a new format. Hopefully someone else has a better solution for you. If it was a Flash file, there might be online converters, but with it being proprietary, I'm not sure.
Canvas is not going to support them in the format they're in -- they don't use standards and what they do use is old technology that browsers either don't support or soon won't support.
I just came across that thread when having a similar problem with extracting a Jar file. After some Google research I came across the following online utility which helped me open a Jar file. After using it I could nicely access all the contents of the file. Hope that helps.