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dimechen
February 25th, 2010, 05:12 PM
I installed libjson-java and everything listed as dependencies via Synaptic and naively thought that I can now do
import net.sf.json.*;
and it will simply work. (This is not an eclipse but a general question; simple editor and running javac in the shell.)
It doesn't. I get this error message:
The package net.sf.json does not exist.
I checked what was installed and found json-lib-2.2.3.jar in /usr/share/java.
There are some other .jar-files in there that I also can't seem to use.
Restarting the computer (a netbook running the ubuntu netbook remix) or putting /usr/share/java on the classpath does not help.
What can I do to let my java know where to find those packages?
Thanks for any advice.
n0dix
February 25th, 2010, 05:22 PM
export CLASSPATH=/usr/share/java/json-lib-2.2.3.jar:.
This is a temporary solution.
Mighty_Joe
February 25th, 2010, 05:55 PM
putting /usr/share/java on the classpath does not help.


You have to specify the actual JAR file on the classpath, as n0dix indicates.
Personally, I either use Ant (http://ant.apache.org/) to build my Java projects or, for smaller projects, write a Bash script to set the CLASSPATH and run javac.
Using the system-wide CLASSPATH for multiple projects gets real tedious real quick.
dimechen
February 25th, 2010, 05:57 PM
Thank you, that works. But as you said, temporarily.
Does anyone have an idea for a long-term solution?
Also, is this what is supposed to happen when I install a java package via synaptic - that it is shoved into some folder and I still have to add it to the classpath manually?
Mighty_Joe
February 26th, 2010, 01:21 PM
Does anyone have an idea for a long-term solution?

I gave you mine in my previous post



Also, is this what is supposed to happen when I install a java package via synaptic - that it is shoved into some folder and I still have to add it to the classpath manually?
I don't know about Synaptic because I develop Java primarily on Windows and Solaris, but that is how it is done on those platforms.
dimechen
February 27th, 2010, 02:22 PM
Hi Joe!
I did see your previous message, but only after I posted my own. Sorry for the confusion.
Thanks also for the second message. I'm a bit less confused about downloading Java packages now. : )
- dimechen