How did you install xerxes2 ? Normally you find these classes in the xerxes.jar. You can check it if you unzip the jar file.
For running your code correctly you have to put xerxes.jar into your classpath.
For seeing it in the
ide's you have to be careful.
Not every ide is updating the auto completition automaticly when you mount a jar file.
So e.g in Netbeans you first have to update your parser database yourself