@Override
  public Exporter<?, ?> getExporter(DataVertical transferDataType) {
    Preconditions.checkArgument(initialized);
    Preconditions.checkArgument(SUPPORTED_SERVICES.contains(transferDataType));
    return exporterMap.get(transferDataType);
  }
TransferExtension to kick off the Transfer jobs to/from Apple
extensions/data-transfer/portability-data-transfer-apple/src/main/java/org/datatransferproject/datatransfer/apple/AppleTransferExtension.java