Optional int parameter 'rows' is not present but cannot be translated into a null value due to being declared as a primitive type.

我的spring mvc 代码：

@Controller
@RequestMapping("/product")
public class Fancy {
    @RequestMapping(value = "/fancy")
    @ResponseBody
    public String showFancy(@RequestParam(value = "page", required = false) int page) {
        return "{\"status\":\"ok\"+}"+page+"\t";
    }
}  

报错：

 Optional int parameter 'rows' is not present but cannot be translated into a null value due to being declared as a primitive type. Consider declaring it as object wrapper for the corresponding primitive type.

大意是说 如果参数是非必须的，则会赋值为null，因此参数应该是一个object，它才能接受这个null值。

而上面代码参数page 的类型 为 int，它接受不了null值。

解决方法:

将int 改为 对象类型 Integer :

@RequestParam(value = "page", required = false) Integer page  

问题解决！end.