You could do
boolean cookiePresent = Arrays.toList( request.getCookies() ).contains( "cookie_name" );
but the array will still be looped through, behind the scenes (with this code, twice, I think).
If it's something you check often, set a session attribute to denote that you checked. Then you only have to 'pay' for the check once, after that, it's as efficient as it's going to get.