What you are asking for is fundamentally wrong. POST requests sends data in a body payload, which is mapped via @RequestBody. @RequestParam is used to map data through the URL parameters such as /url?start=foo. What you are trying to do is use @RequestParam to do the job of @RequestBody.
@RequestBody Map<String, String> payload. Be sure to include ‘Content-Type‘: ‘application/json‘ in your request header.@RequestParam, use a GET request instead and send your data via URL parameters.@ModelAttribute.@RequestBody Map<String, String> payload. To do this, please see this answer.It is not possible to map form data encoded data directly to a Map<String, String>.
原文:https://www.cnblogs.com/sidesky/p/15185929.html