The registry is a very Windows-specific thing.
Java is a platform-independent language, meant to work on many different operating systems. Therefore it does not contain classes and methods in the standard Java API for functionality that is very specific to a particular operating system.
There are libraries that you can get to work with the Windows registry from Java; Google for example for "java windows registry" to find them. I don't know if there's one that will support the functionality that you need, you'll have to check that out.