Generate the package index.
PackageListWriter packgen;
String filename = "package-list";
try {
packgen = new PackageListWriter(filename);
packgen.generatePackageListFile(root);
packgen.close();
} catch (IOException exc) {
Standard.configuration().standardmessage.error("doclet.exception_encountered",
exc.toString(), filename);
throw new DocletAbortException();
}