* the service will transition to the {@link Service.State#FAILED} state and this method will no
   * longer be called.
   */
  protected abstract void runOneIteration() throws Exception;

  /**
   * Start the service.
   *
   * <p>By default this method does nothing.
   */
  protected void startUp() throws Exception {}

  /**

   * values. This includes both successful load operations and those that threw exceptions. This is
   * defined as {@code loadSuccessCount + loadExceptionCount}.
   *
   * <p><b>Note:</b> the values of the metrics are undefined in case of overflow (though it is
   * guaranteed not to throw an exception). If you require specific handling, we recommend
   * implementing your own stats collector.
   */

   * values. This includes both successful load operations and those that threw exceptions. This is
   * defined as {@code loadSuccessCount + loadExceptionCount}.
   *
   * <p><b>Note:</b> the values of the metrics are undefined in case of overflow (though it is
   * guaranteed not to throw an exception). If you require specific handling, we recommend
   * implementing your own stats collector.
   */

   * @param len an int specifying the number of bytes to read.
   * @throws EOFException if this stream reaches the end before reading all the bytes.
   * @throws IOException if an I/O error occurs.
   */
  public static void readFully(InputStream in, byte[] b, int off, int len) throws IOException {
    int read = read(in, b, off, len);
    if (read != len) {
      throw new EOFException(

            throws ModelBuilderException {
        ModelBuilderResult result = buildModel(session, src);
        Model model = result.getRawModel();
        return transformPom(model, project);
    }

    protected Model buildBomWithoutFlatten(RepositorySystemSession session, MavenProject project, ModelSource src)
            throws ModelBuilderException {

   * function that also supports reverse conversion.
   *
   * <p>If you are okay with {@code null} being returned for an unrecognized key (instead of an
   * exception being thrown), you can use the method reference {@code map::get} instead. Note that
   * it is not serializable unless you explicitly make it {@link Serializable}, typically by writing
   * {@code (Function<K, V> & Serializable) map::get}.

     * directory or a {@code pom.xml} file with the {@code root="true"} attribute.
     * If there's no such directory, an {@code IllegalStateException} will be thrown.
     *
     * @throws IllegalStateException if the root directory could not be found
     * @see #getTopDirectory()
     * @since 4.0.0
     */
    Path getRootDirectory();

    /**
     * @since 3.3.0
     */

   *
   * <p><b>Java 8+ users:</b> the {@code Stream} equivalent to this method is {@code
   * stream.collect(MoreCollectors.onlyElement())}.
   *
   * @throws NoSuchElementException if the iterable is empty
   * @throws IllegalArgumentException if the iterable contains multiple elements
   */
  @ParametricNullness
  public static <T extends @Nullable Object> T getOnlyElement(Iterable<T> iterable) {

   *
   * <p><b>Java 8+ users:</b> the {@code Stream} equivalent to this method is {@code
   * stream.collect(MoreCollectors.onlyElement())}.
   *
   * @throws NoSuchElementException if the iterable is empty
   * @throws IllegalArgumentException if the iterable contains multiple elements
   */
  @ParametricNullness
  public static <T extends @Nullable Object> T getOnlyElement(Iterable<T> iterable) {

      throws IOException {
    testStreamingEncodes(encoding, decoded, encoded);
    testStreamingDecodes(encoding, encoded, decoded);
  }

  @GwtIncompatible // Writer
  private static void testStreamingEncodes(BaseEncoding encoding, String decoded, String encoded)
      throws IOException {
    StringWriter writer = new StringWriter();