MissingServletRequestParameterException: Required request parameter ‘id‘ for method parameter type I

1、报错信息
1.1idea中报错信息

Resolved [org.springframework.web.bind.MissingServletRequestParameterException: Required request parameter 'id' for method parameter type Integer is not present]

1.2网页报错信息

Whitelabel Error Page
This application has no explicit mapping for /error, so you are seeing this as a fallback.

Sun Nov 14 15:36:12 CST 2021
There was an unexpected error (type=Bad Request, status=400).
Required request parameter 'id' for method parameter type Integer is not present
org.springframework.web.bind.MissingServletRequestParameterException: Required request parameter 'id' for method parameter type Integer is not present

2、报错原因
2.1Controller里面代码如下，需要传参

	@GetMapping("/getbook")
    @ResponseBody
    public Book getBook(@RequestParam("id") Integer id){
    
    
        Book bookById = bookService.getBookById(id);
        return bookById;
    }

2.2前端网址如下，没有传参

http://localhost:8086/getbook

3、解决办法，传入参数

http://localhost:8086/getbook?id=1

3.1网页运行结果（@ResponseBody返回字符串）

{
    
    "id":1,"name":"热岛效应","password":null}