/** Measures memory usage information and stores it in the model. */
 public static void main(String[] args) throws IOException, ClassNotFoundException {
   Root root = Root.fromFile(args[0]);
   root.baseline = baseline();
   for (LoadedClass loadedClass : root.loadedClasses.values()) {
     if (loadedClass.systemClass) {
       loadedClass.measureMemoryUsage();
     }
   }
   root.toFile(args[0]);
 }