What is the easiest way to have an application launch at startup on Ubuntu server as daemon? This is a java application (java com.run.run.Run) etc.
How would I have it launch as a user and possibly have access to write to some log file where the user has permissions to write?
And if I don't end up doing that, how would I launch the application as the root user at startup.
Edited: It is a headless server, I don't have access to the desktop applications.
As user upon login: Depends on when exactly you want it to start. Wanting to run it a a user and write files as the user seems to indicate that you want to run it at login. This can be achieved by adding it under
System -> Preferences -> Sessions -> Statup Programs
or
System -> Preferences -> Startup applications
Depending on your version of gnome.
Or, put a call to your java program it in ~/.profile.
As root upon boot: To run it as root during boot, follow the instructions at http://embraceubuntu.com/2005/09/07/adding-a-startup-script-to-be-run-at-bootup/
So you have a script of your own that you want to run at bootup, each time you boot up. This will tell you how to do that.
Write a script. put it in the /etc/init.d/ directory. Lets say you called it FOO. You then run
% update-rc.d FOO defaults
You also have to make the file you created, FOO, executable, using $chmod +x FOO
Using Headless Mode in the Java SE Platform may give you some additional latitude, depending on what your daemon does. In addition or @aioobe's suggestions, consider SuperUser.com for questions about startup and permissions.