public synchronized AppleMusicInterface getOrCreateMusicInterface(
          UUID jobId,
          TokensAndUrlAuthData authData,
          AppCredentials appCredentials,
          String exportingService,
          Monitor monitor) {
    return (AppleMusicInterface) interfacesByAuthData
            .computeIfAbsent(jobId, key -> makeMusicInterface(authData, appCredentials,
                    exportingService, monitor));
  }
The Factory class that creates the Apple Import Extensions.
extensions/data-transfer/portability-data-transfer-apple/src/main/java/org/datatransferproject/datatransfer/apple/AppleInterfaceFactory.java