How to validate Spring MVC @PathVariable values?

Question

For a simple RESTful JSON api implemented in Spring MVC, can I use Bean Validation (JSR-303) to validate the path variables passed into the handler method?

For examp

Answer 1

Instead of using @PathVariable, you can take advantage of Spring MVC ability to map path variables into a bean:

@RestController
@RequestMapping("/user")
public class UserController {

    @GetMapping("/{id}")
    public void get(@Valid GetDto dto) {
        // dto.getId() is the path variable
    }

}

And the bean contains the actual validation rules:

@Data
public class GetDto {
     @Min(1) @Max(99)
     private long id;
}

Make sure that your path variables ({id}) correspond to the bean fields (id);