参考：https://blog.csdn.net/coder_what/article/details/113250720
Spring MVC源码—— @RequestBody和@ResponseBody原理解析（版本：Spring Framework 5.1.7.RELEASE）

对于url解析参数来说，有两个注解，分别是pathVariable（指一种占位符）和requestParam,对于body来说，有requestBody。不加注解，也可以直接把url转为对应参数或者实体类

1、@PathVariable: www.666.com/web/6

  1. @GetMapping("/web/{node}")
  2. public ReturnType listEmployeeInNode(@PathVariable String node) throws BusinessException {
  3. }

2、@ReqeustParam: www.666.com/web?user=1

  1. @GetMapping("/web")
  2. public ReturnType listEmployeeInNode(@RequestParam("user") String node) throws BusinessException {
  3. }

3、@RequestBody: www.666.com/web body中是json

  1. @GetMapping("/web")
  2. public ReturnType listEmployeeInNode(@RequestBody UserDTO userDto) throws BusinessException {
  3. }

4、无注解：www.666.com/web?userId=1&pwd=2

  1. @PostMapping("/web")
  2. public ReturnType listEmployeeInNode(UserDTO userDto) throws BusinessException {
  3. }