This week's book giveaway is in the Mac OS forum. We're giving away four copies of a choice of "Take Control of Upgrading to Yosemite" or "Take Control of Automating Your Mac" and have Joe Kissell on-line! See this thread for details.
What's wrong ??? Yikes! I'm not sure. When does the problem occur? When compiling? When running? What OS are you using? What version of Java? This looks like it might be a JVM problem. If nothing else seems to work, perhaps uninstalling your JRE and then reinstalling it will help. What happens when you try a very simple Java program, such as the following?