code: public static boolean handleIfMatch(final HttpServerExchange exchange, final List<ETag> etags, boolean allowWeak) {
          return handleIfMatch(exchange.getRequestHeaders().getFirst(Headers.IF_MATCH), etags, allowWeak);
      }
docs: Handles the if-match header. returns true if the request should proceed, false otherwise
  
  @param exchange the exchange
  @param etags    The etags
  @return