question: @ RequestMapping ( value = "/{bookmarkId}" , method = RequestMethod . DELETE ) public ResponseEntity < Bookmark > deleteBookmark ( @ PathVariable ( value = "username" ) String username , @ PathVariable ( value = "bookmarkId" ) int bookmarkId ) throws BookmarkNotFoundException { Optional < Bookmark > optional = bookmarksRepository . findByIdAndUserUsername ( bookmarkId , username ) ; if ( optional . isPresent ( ) ) { bookmarksRepository . delete ( optional . get ( ) ) ; return new ResponseEntity < > ( optional . get ( ) , HttpStatus . OK ) ; } else { throw new BookmarkNotFoundException ( "Bookmark not found. id = " + bookmarkId ) ; } }
target:  A method to delete a bookmark identified by id.