class FileUtil {

  public static Path copyFile(Path _source_file, Path _target_dir) throws IOException {
    final Path to = _target_dir.resolve(_source_file.getFileName());
    try (final InputStream is = new FileInputStream(_source_file.toFile());
        final OutputStream os = new FileOutputStream(to.toFile())) {
      final byte[] byte_buffer = new byte[1024];
      int len = 0;
      while ((len = is.read(byte_buffer)) != -1) os.write(byte_buffer, 0, len);
    }
    return to;
  }

}