What behavior will the method have if both @RequestMapping and @PostMapping are specified in the annotation?

In Spring MVC, the @PostMapping annotation is a specialized shortcut for @RequestMapping with the HTTP POST method. If both @RequestMapping and @PostMapping are specified on the same method, the behavior will depend on the parameters set in each annotation.

• If @RequestMapping specifies a method (e.g., method = RequestMethod.GET), and @PostMapping is for POST, there is a conflict, and Spring may not clearly determine which HTTP method to handle.
• Usually, @PostMapping is equivalent to @RequestMapping(method = RequestMethod.POST), so duplicating them is unnecessary and can lead to errors or unpredictable behavior.

It is recommended to use either @RequestMapping with an explicit method or specialized annotations (@PostMapping, @GetMapping, etc.), but not both on the same method.

Example of correct usage:

@PostMapping("/submit")
public ResponseEntity<String> submitData() {
    // handle POST request
}

If both annotations are used, it is better to check how they are configured to avoid conflicts.