Converting resultset to JSON

[Em Aiy]

I need to convert my resultset (being retrieved from jdbc query) to json. But i am not giving a clue to do it. (i don't have that much expereince in javA)

the resultset i have consists of 4 fields

1: user
2: windowTitle
3: application
4: duration

and there will be number of entries. i.e its like this list

List<ActivityVO> activityVOList = empService.listAllActivities();

Please guide me.