显然杰克逊无法反序列化将JSON传递给 Integer 。如果您坚持通过请求正文发送用户的JSON表示，则应将 userId 封装在另一个bean中，如下所示：

Obviously Jackson can not deserialize the passed JSON into an Integer. If you insist to send a JSON representation of a User through the request body, you should encapsulate the userId in another bean like the following:

public class User {
    private Integer userId;
    // getters and setters
}

然后使用该bean作为处理程序方法参数：

Then use that bean as your handler method argument:

@RequestMapping(...)
public @ResponseBody Record getRecord(@RequestBody User user) { ... }

如果你不喜欢创建另一个bean的开销，你可以通过 userId 作为路径变量的一部分，例如 /的getUser / 15 。为了做到这一点：

If you don't like the overhead of creating another bean, you could pass the userId as part of Path Variable, e.g. /getuser/15. In order to do that:

@RequestMapping(value = "/getuser/{userId}", method = POST, produces = "application/json")
public @ResponseBody Record getRecord(@PathVariable Integer userId) { ... }

由于您不再在请求正文中发送JSON，因此应删除消耗属性。

Since you no longer send a JSON in the request body, you should remove that consumes attribute.