This would be great as it would allow my xml stuff to read json w/out any change except for the different sax parser.
If you meant, event-based parser then there are a couple of projects out there that do this:
http://code.google.com/p/json-simple/
Stoppable SAX-like interface for streaming input of JSON text
This project has moved to https://github.com/fangyidong/json-simple
http://jackson.codehaus.org/Tutorial
Jackson Streaming API is similar to Stax API
This project has moved to https://github.com/FasterXML/jackson-core