This example uses the steps that are described in the Download Files to a Local System from a Library Item procedure.

import com.vmware.content.library.item.DownloadSession;
import com.vmware.content.library.item.downloadsession.File;
import com.vmware.content.library.item.DownloadSessionModel;
...
 
// Access the DownloadSession service.
     DownloadSession downloadSessionService = serviceManager.getVapiService(DownloadSession.class);

// Create a new download session model. 
     DownloadSessionModel downloadSessionModel = new DownloadSessionModel();
     downloadSessionModel.setLibraryItemId(libItem.getId());
     String downloadSessionId = downloadSessionService.create(UUID.randomUUID().toString(), downloadSessionModel);

// Access the File service and retrieve the files you want to export.
     File downloadFileService = serviceManager.getVapiService(File.class);
     List<FileTypes.Info> downloadFileInfos = downloadFileService.list(downloadSessionId);
     for (FileTypes.Info downloadFileInfo : downloadFileInfos) {

// Make sure all files are in the prepared state before you precede with the downloading operation.
         downloadFileService.prepare(downloadSessionId, downloadFileInfo.getName(), EndpointType.HTTPS);
         long timeOut = 360;
         Long endTime = System.currentTimeMillis() + timeOut * 1000;
         try {
              Thread.sleep(5000);
         } catch (InterruptedException e) {
                   System.out.println(e);
         }
         FileTypes.PrepareStatus expectedStatus = com.vmware.content.library.item.downloadsession.File.PrepareStatus.PREPARED;
         downloadFileInfo = downloadFileService.get(downloadSessionId, downloadFileInfo.getName());
         FileTypes.PrepareStatus currentStatus = downloadFileInfo.getStatus();
         if (currentStatus == expectedStatus) {

// When the files are prepared, you can retrieve the download information for each file.
            downloadFileInfo = downloadFileService.get(downloadSessionId, downloadFileInfo.getName());
            try {
                 URI downloadUri = downloadFileInfo.getDownloadEndpoint().getUri();
                 String downloadUrl = downloadUri.toURL().toString();

// Execute an HTTP GET request and pass the download endpoints of the files. 
                 HttpClient httpClient = new HttpClient(true);
                 InputStream inputStream = httpClient.downloadFile(downloadUrl);
                 String fileNameDownload = downloadFileInfo.getName();
                 File tmpDir = new java.io.File("tmp");
                 tmpDir.mkdir();
                 String fullPath = tmpDir.getAbsolutePath() + 
                       System.getProperty("file.separator") + fileNameDownload;

// Copy the files to the directory on your machine.
                 Files.copy(inputStream, Paths.get(fullPath),StandardCopyOption.REPLACE_EXISTING);
            } catch (MalformedURLException e) {
               System.out.println("Failed to download due to IOException!" + e);
               throw new RuntimeException("Failed to download due to IOException!", e);
            } catch (IOException e) {
               System.out.println("IO exception during download" + e);
               throw new RuntimeException("Failed to download due to IOException!", e);

// Delete the download session after all files are downloaded.
            } finally {
                 downloadFileService.delete(downloadSessionId);
            }
        } else {
            while (endTime > System.currentTimeMillis()) {
                downloadFileInfo = downloadFileService.get(downloadSessionId,
                             downloadFileInfo.getName());
                currentStatus = downloadFileInfo.getStatus();
                if (currentStatus == expectedStatus) {
                    return;
                } else if (currentStatus == com.vmware.content.library.item.downloadsession.File.PrepareStatus.ERROR) {
                   System.out.println("DownloadSession Info : " + downloadSessionService.get(downloadSessionId));
                  throw new RuntimeException("Error while waiting for download file status to be PREPARED...");
              }
          }
      }
   }