I needed to find the version of a jar file I was using to help out our middleware team at work and had never needed to do so before, so I went to googling. I figured it would be pretty straightforward and it is, once you find the correct commands. I initially started out unzipping the jar file and found the version that way through the manifest file by looking at the Implementation-Version. It wasn’t too much work, but I knew there had to be a better way and I stumbled upon this stackoverflow answer
If you open a terminal window and cd to the directory with your jar file you can do
unzip -p file.jar META-INF/MANIFEST.MF to view the manifest file without manually unzipping the file.