I downloaded Minecraft. I created a 'Portable Apps' directory under Home. I then right-clicked 'Minecraft.jar' and selected 'Make Link'.
I then moved the "shortcut" to the desktop.
When I try to launch Minecraft from that shortcut, I either get errors or Minecraft saves a whole bunch of random data files to the desktop.
Why can't Ubuntu create proper shortcuts like Windows? Why does it treat shortcuts like actual programs? Why isn't a "Link" a link? Why is it the actual program?
The proper way to use a portable app like this under Ubuntu requires also creating a "*.desktop" file for its executable (which is "Minecraft.jar" in this case), and putting it in one of these folders: /usr/share/applications, /usr/local/share/applications, or /home/jay/.local/share/applications (which looks like the one you would prefer).
If you want a "shortcut" for this app on your desktop as well, you should simply copy that "*.desktop" file to your desktop. It's OK to create shortcuts for files, folders, and other places, but it's not advisable to do the same for apps in this case.
Here's a sample file, which you might name as "minecraft.desktop", which is simply a plain text file given executable permissions.
[Desktop Entry]
Version=1.0
Type=Application
Name=Minecraft
Comment=Java minecraft game
Exec="/home/jay/Portable Apps/Minecraft.jar"
Icon="/home/jay/Portable Apps/Minecraft.png"
Categories=Games;
StartupNotify=true
Terminal=false
It's assumed above that your user name is jay and you also have an icon file named "Minecraft.png", otherwise you should better have one.
Does the original 'Minecraft.jar' work correctly? I'm thinking that maybe there is a problem in how Ubuntu is handling your .jar files. If that's the problem, read this thread.
I have tried two methods to make desktop shortcuts: the right click → make link and right click → copy to. I mostly use copy to for the executable files usually found on /usr/share/applications. I know that copy to doesn't really create a shortcut, but it does the job for me.
