Question

Browsing through the source of a spring framework project i came across a method that looked like this:

@RequestMapping("primitive")
public @ResponseBody String primitive(@RequestParam Integer value) {
    return "Converted primitive " + value;
}

Being only a casual java user, ive not come across this before. As far as i was aware, the @ symbol preceded java annotations, yet there appear to be annotations in the method signature itself. What are the @ResponseBody and @RequestParam sections doing?

Answer 1

The @ResponseBody is actually just a Plain-Jane Method annotation. You’re allowed to put them after the scope keyword.

The @RequestParam annotation isn’t part of the method signature. It’s a Parameter Annotation.