validation url

AuthorController.java

@GetMapping(value = "/{id}")
	public ResponseWrapper<Author> getAuthorById(
			@Valid @Pattern(regexp = REGEX_FOR_NUMBERS, message = MESSAGE_FOR_REGEX_NUMBER_MISMATCH) @PathVariable(value = "id") String id )
	{
		return new ResponseWrapper<>( authorMainService.getById( Integer.parseInt( id ) ), HttpStatus.OK );
	}