The class hierarchy is now in .jar and .zip files in the /usr/java/lib
directory.  Previously, the system classes were installed under
/usr/java/classes.  This probably will not matter to you unless you
are using the -classpath option or the Invocation API.  For more
details, see our HTML release notes starting at

    file:/usr/java/webdocs/release.html

particularly the section on "Setting up your Environment".

