Ever tried doing this? java -cp "." -jar Sample.jar Doesn't work, does it! I found out it the hard way. I actually had to debug all the way down to logging all the classpath in the program. Java(1) 'does' spell this out. -jar Execute a program encapsulated in a JAR file. The first argument is the name of a JAR file instead of a startup class name. In order for this option to work, the manifest of the JAR file must contain a line of the form Main-Class: classname . Here, classname identifies the class having the public static void main(String[] args) method that serves as your application’s starting point. See the Jar tool reference page and the Jar trail of the Java Tutorial for information about working with Jar files and Jar-file manifests. When you use this option, the JAR file is the source of all user classes, and other user class path settings are ignored. Note that JAR files that can be run with the “java -jar” option can ...
Universe from my perspective..