try {
            Enumeration<URL> urls = loader.getResources(BUILDER.getExtensionDescriptorLocation());
            while (urls.hasMoreElements()) {

                try (InputStream is = urls.nextElement().openStream()) {
                    ExtensionDescriptor descriptor = BUILDER.build(is);
                    artifacts.addAll(descriptor.getExportedArtifacts());
                    packages.addAll(descriptor.getExportedPackages());

  @Override
  public boolean wasStreamOpened() {
    return inputStreamOpened;
  }

  @Override
  public boolean wasStreamClosed() {
    return inputStreamClosed;
  }

  @Override
  public InputStream openStream() throws IOException {
    inputStreamOpened = true;
    return new RandomAmountInputStream(new In(), new Random());
  }

  private final class In extends TestInputStream {

    public In() throws IOException {

  @Override
  public boolean wasStreamOpened() {
    return inputStreamOpened;
  }

  @Override
  public boolean wasStreamClosed() {
    return inputStreamClosed;
  }

  @Override
  public InputStream openStream() throws IOException {
    inputStreamOpened = true;
    return new RandomAmountInputStream(new In(), new Random());
  }

  private final class In extends TestInputStream {

    public In() throws IOException {

        this.url = Objects.requireNonNull(url, "url cannot be null");
        this.hashCode = Objects.hashCode(url);
    }

    @Override
    public InputStream getInputStream() throws IOException {
        return url.openStream();
    }

    @Override
    public String getLocation() {
        return url.toString();
    }

    /**
     * Gets the URL of this source.
     *

    // Slice it starting at offset 10.
    ByteSource slice = source.slice(10, 5);

    // Open a stream to the slice.
    InputStream in = slice.openStream();

    // Append 10 more bytes to the source.
    source.append(newPreFilledByteArray(5, 10));

    // The stream reports no bytes... importantly, it doesn't read the byte at index 5 when it

            while (resources.hasMoreElements()) {
                URL resource = resources.nextElement();
                try {
                    InputStream is = resource.openStream();
                    final Properties properties = new Properties();
                    if (is != null) {
                        try (InputStream in = is) {
                            properties.load(in);

    for (int i = 0; i < size; i++) {
      array[i] = (byte) (offset + i);
    }
    return array;
  }

  private static void copy(URL url, File file) throws IOException {
    InputStream in = url.openStream();
    try {
      OutputStream out = new FileOutputStream(file);
      try {
        byte[] buf = new byte[4096];
        for (int read = in.read(buf); read != -1; read = in.read(buf)) {

  }

  @Override
  protected void setUp() throws Exception {
    this.source = factory.createSource(data);
  }

  public void testOpenStream() throws IOException {
    Reader reader = source.openStream();

    StringWriter writer = new StringWriter();
    char[] buf = new char[64];
    int read;
    while ((read = reader.read(buf)) != -1) {
      writer.write(buf, 0, read);
    }
    reader.close();

    // read the first 8 chars manually, since there's no equivalent to ByteSource.slice
    // TODO(cgdecker): Add CharSource.slice?
    StringBuilder builder = new StringBuilder();
    Reader reader = concatenated.openStream(); // no need to worry about closing
    for (int i = 0; i < 8; i++) {
      builder.append((char) reader.read());
    }
    assertEquals(expected, builder.toString());
  }

     *
     * @return a byte stream to the source contents, never {@code null}
     * @throws IOException in case of IO issue
     */
    @Nonnull
    InputStream openStream() throws IOException;

    /**
     * Provides a user-friendly hint about the location of the source.
     * This could be a local file path, a URI or just an empty string.