/** Initialized in [callStart]. */
  private var callStackTrace: Any? = null

  /** Finds an exchange to send the next request and receive the next response. */
  private var exchangeFinder: ExchangeFinder? = null

  var connection: RealConnection? = null
    private set
  private var timeoutEarlyExit = false

  /**

            if (server.getConfiguration() != null) {
                XmlNode dom = server.getDelegate().getConfiguration();
                List<XmlNode> children = dom.getChildren().stream()
                        .filter(c -> !"wagonProvider".equals(c.getName()))
                        .collect(Collectors.toList());
                dom = new XmlNodeImpl(dom.getName(), null, null, children, null);

  private var rawSocket: Socket? = null

  /**
   * The application layer socket. Either an [SSLSocket] layered over [rawSocket], or [rawSocket]
   * itself if this connection does not use SSL.
   */
  internal var socket: Socket? = null
  private var handshake: Handshake? = null
  private var protocol: Protocol? = null
  private var source: BufferedSource? = null
  private var sink: BufferedSink? = null

     *
     * @param project The project to try to resolve the artifact from, must not be <code>null</code>.
     * @param requestedArtifact The artifact to resolve, must not be <code>null</code>.
     * @return The matching artifact from the project or <code>null</code> if not found. Note that this
     */
    private Artifact findMatchingArtifact(MavenProject project, Artifact requestedArtifact) {

            VersionResult result) {
        Versioning versioning = null;
        try {
            if (metadata != null) {
                try (SyncContext syncContext = syncContextFactory.newInstance(session, true)) {
                    syncContext.acquire(null, Collections.singleton(metadata));

                    if (metadata.getPath() != null && Files.exists(metadata.getPath())) {

        localRepositoryPath = (localRepository != null) ? new File(localRepository) : null;

        return this;
    }

    @Override
    public MavenExecutionRequest setSystemProperties(Properties properties) {
        if (properties != null) {
            this.systemProperties = SystemProperties.copyProperties(properties);
        } else {
            this.systemProperties = null;
        }

        return this;

        if (repositories != null && mirrors != null) {
            for (ArtifactRepository repository : repositories) {
                Mirror mirror = MavenRepositorySystem.getMirror(repository, mirrors);
                injectMirror(repository, mirror);
            }
        }
    }

    private void injectMirror(ArtifactRepository repository, Mirror mirror) {
        if (mirror != null) {

        this.groupId = (groupId != null && !groupId.isEmpty()) ? groupId : null;
        this.artifactId = (artifactId != null && !artifactId.isEmpty()) ? artifactId : null;
        this.classifier = (classifier != null && !classifier.isEmpty()) ? classifier : null;
        this.extension = (extension != null && !extension.isEmpty()) ? extension : null;

        if (parent != null) {
            validateStringNotEmpty(
                    "parent.version", problems, Severity.FATAL, Version.BASE, parent.getVersion(), parent);
        }
    }

    private void validate30RawProfileActivation(ModelProblemCollector problems, Activation activation, String prefix) {
        if (activation == null || activation.getFile() == null) {
            return;
        }

     *
     * @param groupId The group id, may be {@code null}.
     * @param artifactId The artifact id, may be {@code null}.
     * @param version The version, may be {@code null}.
     * @return The user-friendly artifact id, never {@code null}.
     */
    static String toId(String groupId, String artifactId, String version) {
        return ((groupId != null && !groupId.isEmpty()) ? groupId : "[unknown-group-id]")
                + ':'