We can add launchers either in the Desktop or on panels.
To add one, right click the panel and select "Add to panel...", you will get the "Add to panel" window.
Here double click on "custom application launcher".
On the "Create launcher" window, for name type "Idea" and for the command type:
/bin/sh -c 'export JDK_HOME=path for Java home && path for /bin/idea.shE.g.
/bin/sh -c 'export JDK_HOME=/usr/lib/jvm/java-6-sun-184.108.40.206 && /home/suho/proj/idea-IU-95.66/bin/idea.sh'
By clicking the launcher icon on the "Create launcher" window you can select an image file to add as the icon of your launcher. For Idea you can find its image form