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.
then you can use BufferedReader's readLine() method to see when the user presses enter. Probably not as simple as you are looking for, but I think that is about as simple as it gets with the standard API