JAXBContext contextBookInformation;
JAXBContext contextBookInformationDetailed;

public BookManager() {
  try {
    contextBookInformation = JAXBContext.newInstance(BookInformation.class);
    contextBookInformationDetailed = JAXBContext.newInstance(BookInformationDetailed.class);
  } catch (Exception exception) {
    System.out.println("An exception has occurred: " + exception.getMessage());
    if (Constants.DEBUG) {
      exception.printStackTrace();
    }
  }
  // ...
}