code: @Override
    public void visit(final Visitable visitable) {
      if (visitable instanceof Auditable) {
        modified |= ((Auditable) visitable).isModified();
      }
    }
docs: Visits all Auditable, Visitable objects in an object graph hierarchy in search of any modified objects.
  
  @param visitable the Visitable object visited by this Visitor.
  @see org.cp.elements.lang.Auditable#isModified()