Recently I'm using JPA and jsog to produce the connect between web page and server. One question is that in many-to-many associations, when trying to serialize one object, many other objects will be serialized too, which could result in a much too huge json. Also, when trying to update a date through front-end, I have to send a huge json to server, even if it's just a small change in string. So if I want to less the json I need to send, what can I do?