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

You can use like this: use org.springframework.validation.annotation.Validated to valid RequestParam or PathVariable.

 *
 * Variant of JSR-303's {@link javax.validation.Valid}, supporting the
 * specification of validation groups. Designed for convenient use with
 * Spring's JSR-303 support but not JSR-303 specific.
 *

step.1 init ValidationConfig

@Configuration
public class ValidationConfig {
    @Bean
    public MethodValidationPostProcessor methodValidationPostProcessor() {
        MethodValidationPostProcessor processor = new MethodValidationPostProcessor();
        return processor;
    }
}

step.2 Add @Validated to your controller handler class, Like:

@RequestMapping(value = "poo/foo")
@Validated
public class FooController {
...
}

step.3 Add validators to your handler method:

   @RequestMapping(value = "{id}", method = RequestMethod.DELETE)
   public ResponseEntity delete(
           @PathVariable("id") @Size(min = 1) @CustomerValidator int id) throws RestException {
        // do something
        return new ResponseEntity(HttpStatus.OK);
    }

final step. Add exception resolver to your context:

@Component
public class BindExceptionResolver implements HandlerExceptionResolver {

    @Override
    public ModelAndView resolveException(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) {
        if (ex.getClass().equals(BindException.class)) {
            BindException exception = (BindException) ex;

            List fieldErrors = exception.getFieldErrors();
            return new ModelAndView(new MappingJackson2JsonView(), buildErrorModel(request, response, fieldErrors));
        }
    }
}