This week's book giveaway is in the OCMJEA forum. We're giving away four copies of OCM Java EE 6 Enterprise Architect Exam Guide and have Paul Allen & Joseph Bambara on-line! See this thread for details.
You cannot run the JAR file because it wasn't created to do so. I suspect that it contains many separate examples and is not meant to be run as a single program. To run the individual examples, you can use
jar xvf codeKitchens.jar
to extract them first. Then you probably need to compile and run each one separately.