Anyhow, I got tired of being told to update each time I started the application. Plus, I like being up to date. Since Ubuntu only gets an updated version of JOSM with each new release of Ubuntu, I decided to find out how to cleanly update JOSM in a way that integrates well with the currently installed JOSM. Here's what I did.
- Go to http://josm.openstreetmap.de/
- Under the Download section, click on the "tested JOSM" link and save it.
- Under a terminal run the following.
sudo cp ~/Downloads/josm-tested.jar /usr/share/josm/
sudo ln -f -s josm-tested.jar josm.jar
Change ~/Downloads/josm-test.jar to the location in which you saved the josm-tested.jar file.
When you first start JOSM you should go ahead and update your plugins.
This was testing in Ubuntu Lucid 10.04, but should work with any version of Ubuntu, and with any version of JOSM. If it doesn't for any reason, respond in the comments below.