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 use the java.lang.Runtime.getRuntime().exec() call to execute a process on the server. Keep in mind that the JSP simply becomes a servlet that executes on the <b>server</b> not the client. I have had good luck executing a shell script on Unix systems or batch (.bat or .cmd) files in Windows. However, if you are executing Java, first look into using the exposed Java API (if there is one) of whatever you are doing and running in the same VM with the following warning <b>Do not call the main method of some Java class from another Java class as often the main method terminates by calling System.exit() which will kill the JVM.</b>