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.
If you are looking for own customized exception for your application. You can extend the respective Exception class and call Super constructors and usally override the methods available in Exception (getCause() and getException() methods).
and to your question why use wrapped Exception ?? It is to localize the exception for a specific Code, Application or API. Also, it provides more information about, and helps in identifying, where the exception has occured.