Spring MVC表单支持对象树初始化的最佳实践

If I have a form-backing object that has a complicated object tree -- say a Person that has a Contact Info object that has an Address object that has a bunch of Strings -- it seems that the object needs to be fully populated with component objects before I can bind to it. So if I'm creating a new Person, I need to make sure it has all the component objects populated off the bat, and if I'm retrieving a Person from the database, I need to make sure that any objects that aren't populated from the database get populated with empty objects.If I have a form-backing object that has a comp