public void download()

in s3-artifact-storage-agent/src/main/java/jetbrains/buildServer/artifacts/s3/download/parallel/strategy/impl/AbstractParallelDownloadStrategy.java [32:85]
49 lines of code
8 McCabe index (conditional complexity)

  public void download(@NotNull String srcUrl,
                       @NotNull Path targetFile,
                       long fileSize,
                       @NotNull FileProgress downloadProgress,
                       @NotNull ParallelDownloadContext downloadContext) throws IOException {
    if (fileSize <= 0) throw new IllegalArgumentException(String.format("File size is not positive (%s)", fileSize));
    S3DownloadConfiguration configuration = downloadContext.getConfiguration();
    FileSplitter fileSplitter = downloadContext.getFileSplitter();

    List<FilePart> fileParts = fileSplitter.split(fileSize);
    if (fileParts.size() == 1) {
      LOGGER.warn(String.format("File %s of size %s should be downloaded in parallel, but was split into only 1 part %s. S3 artifact transport misconfigured?",
                                targetFile, fileSize, fileParts.get(0).getDescription()));
    }

    LOGGER.debug(String.format(
      "Start downloading file %s of size %s from %s in %s parts of min %s MB each (except, possibly, the last) by max %s threads", // MB in logs because not less than 1 MB
      targetFile, fileSize, srcUrl, fileParts.size(), configuration.getMinPartSizeBytes() / (1024 * 1024), Math.min(configuration.getMaxThreads(), fileParts.size())
    ));
    ParallelDownloadState downloadState = new ParallelDownloadState(downloadProgress, downloadContext.getInterruptedFlag());
    try {
      try {
        checkDownloadInterrupted(downloadState);
        beforeDownloadingParts(targetFile, fileParts, fileSize, downloadState, downloadContext);
        LOGGER.debug("Finished preparations before downloading parts of file " + targetFile);
      } catch (Exception e) {
        throw new IOException("Preparations before downloading parts failed", e);
      }

      try {
        checkDownloadInterrupted(downloadState);
        downloadParts(srcUrl, fileParts, targetFile, fileSize, downloadState, downloadContext);
        LOGGER.debug("Finished downloading parts of file " + targetFile);
      } catch (Exception e) {
        throw new IOException("Failed to download file parts", e);
      }

      try {
        checkDownloadInterrupted(downloadState);
        afterDownloadingParts(targetFile, fileParts, fileSize, downloadState, downloadContext);
        LOGGER.debug("Finished post-processing after downloading parts of file " + targetFile);
      } catch (Exception e) {
        throw new IOException("Post-processing after downloading parts failed", e);
      }
    } catch (IOException downloadException) {
      try {
        cleanupUnfinishedDownload(targetFile, fileParts, downloadState, downloadContext);
      } catch (Exception cleanupException) {
        LOGGER.warnAndDebugDetails(String.format("Failed to cleanup unfinished download of file %s: %s", targetFile, cleanupException.getMessage()), cleanupException);
      }

      throw downloadException;
    }
  }