如何从spring引导控制器方法返回JSON对象？

@Controller
public class MyController {
    @RequestMapping("/data")
    @ResponseBody
    public MyData getData() {
        MyData data = new MyData();
        // 设置数据
        return data;
    }
}

@RestController
public class MyController {
    @RequestMapping("/data")
    public MyData getData() {
        MyData data = new MyData();
        // 设置数据
        return data;
    }
}

@Controller
public class MyController {
    @RequestMapping("/data")
    public ResponseEntity<MyData> getData() {
        MyData data = new MyData();
        // 设置数据
        return new ResponseEntity<>(data, HttpStatus.OK);
    }
}