requests.clear();

        PluginPrefixResult result = processResults(request, trace, results, requests);

        if (result != null) {
            return result;
        }

        // second try, refetch all (possibly outdated) metadata that wasn't updated in the first attempt

    @Override
    public ArtifactResolverResult resolve(ArtifactResolverRequest request)
            throws ArtifactResolverException, IllegalArgumentException {
        nonNull(request, "request");
        InternalSession session = InternalSession.from(request.getSession());
        try {
            Map<Artifact, Path> paths = new HashMap<>();

    protected abstract void makeKey( Request request ) throws IOException;
    protected abstract Request peekKey() throws IOException;
    protected abstract void doSend( Request request ) throws IOException;
    protected abstract void doRecv( Response response ) throws IOException;
    protected abstract void doSkip() throws IOException;

    public synchronized void sendrecv( Request request,
                    Response response,

  }

  /**
   * Returns the ratio of cache requests which were misses. This is defined as {@code missCount /
   * requestCount}, or {@code 0.0} when {@code requestCount == 0}. Note that {@code hitRate +
   * missRate =~ 1.0}. Cache misses include all requests which weren't cache hits, including
   * requests which resulted in either successful or failed loading attempts, and requests which

  }

  /**
   * Returns the ratio of cache requests which were misses. This is defined as {@code missCount /
   * requestCount}, or {@code 0.0} when {@code requestCount == 0}. Note that {@code hitRate +
   * missRate =~ 1.0}. Cache misses include all requests which weren't cache hits, including
   * requests which resulted in either successful or failed loading attempts, and requests which

    public V load(K key) {
      return constant;
    }
  }

  /**
   * Returns a {@code new Object()} for every request, and increments a counter for every request.
   * An {@code Integer} loader that returns the key for {@code load} requests, and increments the
   * old value on {@code reload} requests. The load counts are accessible via {@link #getLoadCount}
   * and {@link #getReloadCount}.
   */

    /**
     * @param request
     * @param response
     * @param params
     * @param timeout
     * @param firstKey
     * @return
     * @throws IOException
     */
    private <T extends Response> long prepareRequests ( Request request, T response, Set<RequestParam> params, long timeout ) throws IOException {
        Response curResp = response;
        Request curReq = request;
        long firstKey = 0;

     */
    public static final int NTLMSSP_REQUEST_INIT_RESPONSE = 0x00100000;

    /**
     * ?? According to spec this is NTLMSSP_NEGOTIATE_IDENTIFY
     * 
     * If set, requests an identify level token
     */
    public static final int NTLMSSP_REQUEST_ACCEPT_RESPONSE = 0x00200000;

    /**
     * Requests the usage of the LMOWF
     */

  /**
   * The interval between two unit requests, at our stable rate. E.g., a stable rate of 5 permits
   * per second has a stable interval of 200ms.
   */
  double stableIntervalMicros;

  /**
   * The time when the next request (no matter its size) will be granted. After granting a request,
   * this is pushed further in the future. Large requests push this further than small requests.
   */

    @Override
    public ArtifactResolverResult resolve(ArtifactResolverRequest request)
            throws ArtifactResolverException, IllegalArgumentException {
        nonNull(request, "request");
        InternalSession session = InternalSession.from(request.getSession());
        try {
            Map<Artifact, Path> paths = new HashMap<>();