* connection to an address fails, OkHttp will retry the connection with the next address until
   * either a connection is made, the set of IP addresses is exhausted, or a limit is exceeded.
   */
  @Throws(UnknownHostException::class)
  fun lookup(hostname: String): List<InetAddress>

  companion object {
    /**

 * returns the same bytes as the upstream source. Downstream sources may read data either as it
 * is returned by upstream, or after the upstream source has been exhausted.
 *
 * As bytes are returned from upstream they are written to a local file. Downstream sources read
 * from this file as necessary.
 *

      UnmodifiableIterator<T> iterator) {
    return checkNotNull(iterator);
  }

  /**
   * Returns the number of elements remaining in {@code iterator}. The iterator will be left
   * exhausted: its {@code hasNext()} method will return {@code false}.
   */
  public static int size(Iterator<?> iterator) {
    long count = 0L;
    while (iterator.hasNext()) {
      iterator.next();
      count++;
    }

    get() = if (limit == -1L) -1L else (limit - byteCount)

  fun hasNext(): Boolean = peekHeader() != null

  /**
   * Returns the next header to process unless this scope is exhausted.
   *
   * This returns null if:
   *
   *  * The stream is exhausted.
   *  * We've read all of the bytes of an object whose length is known.
   *  * We've reached the [DerHeader.TAG_END_OF_CONTENTS] of an object whose length is unknown.
   */

 * signatures.
 */
fun Buffer.isProbablyUtf8(): Boolean {
  try {
    val prefix = Buffer()
    val byteCount = size.coerceAtMost(64)
    copyTo(prefix, 0, byteCount)
    for (i in 0 until 16) {
      if (prefix.exhausted()) {
        break
      }
      val codePoint = prefix.readUtf8CodePoint()
      if (Character.isISOControl(codePoint) && !Character.isWhitespace(codePoint)) {
        return false
      }
    }
    return true

 *
 * <p>The value you pass to the parameter {@code steps} should be greater than the length of your
 * iterator, so that this class can check that your iterator behaves correctly when it is exhausted.
 *
 * <p>For example, to test {@link java.util.Collections#unmodifiableList(java.util.List)
 * Collections.unmodifiableList}'s iterator:
 *
 * {@snippet :
 * List<String> expectedElements =

  ) : SocketEffect

  /**
   * On HTTP/2, send a [GOAWAY frame](https://tools.ietf.org/html/rfc7540#section-6.8) immediately
   * after the response and will close the connection when the client's socket is exhausted.
   *
   * On HTTP/1 this closes the socket.
   */
  public object ShutdownConnection : SocketEffect

  /**
   * On HTTP/2 this will send the error code on the stream.
   *

      assertTrue(
          "index " + i + " expected <" + expected + "., actual is exhausted",
          actualIterator.hasNext());

      Object actual = actualIterator.next();
      assertEquals("index " + i, expected, actual);
      i++;
    }
    if (actualIterator.hasNext()) {
      fail("index " + i + ", expected is exhausted, actual <" + actualIterator.next() + ">");
    }
  }

  /**

  fun sourceEmpty() {
    val mediaType = if (null == null) null else "any/thing; charset=${null}".toMediaType()
    val body = "".decodeHex().toResponseBody(mediaType)
    val source = body.source()
    assertThat(source.exhausted()).isTrue()
    assertThat(source.readUtf8()).isEqualTo("")
  }

  @Test
  fun sourceClosesUnderlyingSource() {
    var closed = false

    val body: ResponseBody =
      object : ResponseBody() {

  fun setChunkedBody(
    body: Buffer,
    maxChunkSize: Int,
  ) = apply {
    removeHeader("Content-Length")
    headersBuilder.add(CHUNKED_BODY_HEADER)

    val bytesOut = Buffer()
    while (!body.exhausted()) {
      val chunkSize = minOf(body.size, maxChunkSize.toLong())
      bytesOut.writeHexadecimalUnsignedLong(chunkSize)
      bytesOut.writeUtf8("\r\n")
      bytesOut.write(body, chunkSize)