this.type = type
        }

      /** Add a part to the body. */
      fun addPart(body: RequestBody) =
        apply {
          addPart(Part.create(body))
        }

      /** Add a part to the body. */
      fun addPart(
        headers: Headers?,
        body: RequestBody,
      ) = apply {
        addPart(Part.create(headers, body))
      }

      /** Add a form data part to the body. */

      |
      |Fox
      |--123--
      |
      """.trimMargin().replace("\n", "\r\n")
    val body =
      MultipartBody
        .Builder("123")
        .addPart("Quick".toRequestBody(null))
        .addPart("Brown".toRequestBody(null))
        .addPart("Fox".toRequestBody(null))
        .build()
    assertThat(body.boundary).isEqualTo("123")
    assertThat(body.type).isEqualTo(MultipartBody.MIXED)

    builder = builder.addPart(requestBody)
    builder = builder.addPart(headersOf(), requestBody)
    builder = builder.addPart(null, requestBody)
    builder = builder.addFormDataPart("", "")
    builder = builder.addFormDataPart("", "", requestBody)
    builder = builder.addFormDataPart("", null, requestBody)
    builder = builder.addPart(MultipartBody.Part.create(requestBody))

  @Test fun `multipart round trip`() {
    val body =
      MultipartBody
        .Builder("boundary")
        .setType(MultipartBody.PARALLEL)
        .addPart("Quick".toRequestBody("text/plain".toMediaType()))
        .addFormDataPart("color", "Brown")
        .addFormDataPart("animal", "fox.txt", "Fox".toRequestBody())
        .build()

    val bodyContent = Buffer()

	public final fun addFormDataPart (Ljava/lang/String;Ljava/lang/String;Lokhttp3/RequestBody;)Lokhttp3/MultipartBody$Builder;
	public final fun addPart (Lokhttp3/Headers;Lokhttp3/RequestBody;)Lokhttp3/MultipartBody$Builder;
	public final fun addPart (Lokhttp3/MultipartBody$Part;)Lokhttp3/MultipartBody$Builder;
	public final fun addPart (Lokhttp3/RequestBody;)Lokhttp3/MultipartBody$Builder;
	public final fun build ()Lokhttp3/MultipartBody;

	public final fun addFormDataPart (Ljava/lang/String;Ljava/lang/String;Lokhttp3/RequestBody;)Lokhttp3/MultipartBody$Builder;
	public final fun addPart (Lokhttp3/Headers;Lokhttp3/RequestBody;)Lokhttp3/MultipartBody$Builder;
	public final fun addPart (Lokhttp3/MultipartBody$Part;)Lokhttp3/MultipartBody$Builder;
	public final fun addPart (Lokhttp3/RequestBody;)Lokhttp3/MultipartBody$Builder;
	public final fun build ()Lokhttp3/MultipartBody;

			if !cs.Valid() {
				return oi, InvalidPart{
					PartNumber: part.PartNumber,
				}
			}
			if checksumType.FullObjectRequested() {
				if err := checksum.AddPart(*cs, expPart.ActualSize); err != nil {
					return oi, InvalidPart{
						PartNumber: part.PartNumber,
						ExpETag:    "<nil>",
						GotETag:    err.Error(),
					}
				}
			}

    public void testRemove() throws Exception {
        list.addLast(null);
        list.addLast("1");
        list.addLast("2");
        assertThat(list.remove("3"), is(not(true)));
        assertThat(list.remove("1"), is(true));
        assertThat(list.remove(null), is(true));
        list.clear();
        list.addLast("1");
        list.addLast("2");
        list.addLast("3");
        list.remove(1);

      this.stack = new ArrayDeque<>();
      stack.addLast(expand(root));
    }

    @Override
    protected @Nullable T computeNext() {
      while (!stack.isEmpty()) {
        PostOrderNode<T> top = stack.getLast();
        if (top.childIterator.hasNext()) {
          T child = top.childIterator.next();
          stack.addLast(expand(child));
        } else {
          stack.removeLast();

    @Override
    public void addFirst(E e) {
      assertTrue(Thread.holdsLock(mutex));
      delegate.addFirst(e);
    }

    @Override
    public void addLast(E e) {
      assertTrue(Thread.holdsLock(mutex));
      delegate.addLast(e);
    }

    @Override
    public boolean offerFirst(E e) {
      assertTrue(Thread.holdsLock(mutex));
      return delegate.offerFirst(e);
    }