Optional int parameter 'page' is present but cannot be translated into a null value due to being dec

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 'page' is present but cannot be translated into a null value due to being dec

继续查看出错内容：

Request processing failed; nested exception is java.lang.IllegalStateException: Optional int parameter 'page' is 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。