code: @SuppressWarnings("unchecked")
      public Class loadClass(final SgClass modelClass) {
          Class implClass;
          try {
              implClass = Class.forName(modelClass.getName());
              // The class already exists!
          } catch (final ClassNotFoundException e) {
              implClass = null;
          }
          return implClass;
      }
docs: Tries to load the model class calling <code>Class.forName(..)</code>.
  
  @param modelClass
  Model class to lookup.
  
  @return Class (if it already exists) or null if it's unknown.