spring mvc返回jsonp内容

代码如下：

   import com.alibaba.fastjson.JSONPObject; 

　　@RequestMapping(value = "/method1")
    @ResponseBody
    public JSONPObject method1(Req req,String callback) {
        JSONPObject returnJsonp = new JSONPObject(callback);

        try {
            Object obj = "hello";
            returnJsonp.addParameter(obj);
        } catch (Exception e) {
        }

        return returnJsonp;
    }