class HostsFileReader {

  public HostsFileReader(String inFile,
                         String exFile) throws IOException {
    HostDetails hostDetails = new HostDetails(
        inFile, Collections.emptySet(),
        exFile, Collections.emptyMap());
    current = new AtomicReference<>(hostDetails);
    refresh(inFile, exFile);
  }

  public  HostsFileReader(String inFile,
                         String exFile);
  @Private public  HostsFileReader(String includesFile, InputStream inFileInputStream,
      String excludesFile, InputStream exFileInputStream);

}