View Full Version : [SOLVED] Reboot Ubuntu Using Java

January 9th, 2009, 09:49 PM
Hi, I'm trying to reboot from java using:

Process p = Runtime.getRuntime().exec("shutdown -r 5");

which basically just executes the shutdown command from command line / shell. The problem is that it needs su rights and I'm getting the following output:

shutdown: Need to be root

just as would happen when executing the same command in terminal. So, it's not really a programming question, but does anyone khow would I be able to get this to run?


January 9th, 2009, 09:57 PM
sudo java MyShutdown

where MyShutdown is located within the .class file generated from MyShutdown.java.

If your Java app has a user interface, then replace 'sudo' with 'gksudo'.

January 9th, 2009, 10:15 PM
Thanks for replying.

That may work although I do not run my java program from the terminal, it gets executed using "Sessions" to start when my computer starts up (the reboot code being placed in a conditional in the java code).

sudo prompts for a password, but I'm not there to type it in (the pc is functioning as a server).

Any other ideas please?

January 10th, 2009, 01:16 AM
I finally found out how to do it.

I added the following line to /etc/sudoers

myusername ALL = NOPASSWD: java MyShutdown

then in Gnome Sessions I created an entry with the following command

sudo java MyShutdown

this works. The entry in sudoers means that sudo doesn't prompt for a password for that specific command.

June 9th, 2009, 02:31 PM
I want to run command line program such as,
# ifconfig eth0 up/down
# route add default gw

from a Java program using the Runtime.exec() command. But when I run the program, no message is showing and silently discarded and have no impact on the system.
Plz tell me, how is can be done.
From other commands, such as, ifconfig, route, I can capture the output.

And how can a program be run in privileged mode without any user interaction?

Thanks in advance.