I may not have tried them all, but I’ve tried quite a few including:
- The default libraries from json.org
- Jackson
- XStream
- Google Gson
- JsonMarshaller
- JSON.simple
I ended up going with Google Gson, the library is simple, efficient, intuitive and flexible. It allows you to convert JSON objects directly into equivalent Java POJOs[1] and back again, which makes for clean and simple code.
One annoyance with Gson is that its JSON pretty-printer isn’t verbose enough for my tastes, but at the time of writing (Oct 09) this is on their todo list. Edit (Sep 2011): I created my own JSON pretty-printer that works with Gson – see here for more information.
[1] “Plain Old Java Object”
