Headers.headersOf(
        "cache-control",
        "no-cache",
        "cache-control",
        "no-store",
        "user-agent",
        "OkHttp",
      )
    val headerMap = headers.toMultimap()
    assertThat(headerMap["cache-control"]!!.size).isEqualTo(2)
    assertThat(headerMap["user-agent"]!!.size).isEqualTo(1)
  }

  @Test fun toMultimapUsesCanonicalCase() {
    val headers =

  }

  static <
          T extends @Nullable Object,
          K extends @Nullable Object,
          V extends @Nullable Object,
          M extends Multimap<K, V>>
      Collector<T, ?, M> toMultimap(
          Function<? super T, ? extends K> keyFunction,
          Function<? super T, ? extends V> valueFunction,
          Supplier<M> multimapSupplier) {
    checkNotNull(keyFunction);

   *
   *  * `Authorization`
   *  * `Cookie`
   *  * `Proxy-Authorization`
   *  * `Set-Cookie`
   */
  override fun toString(): String = commonToString()

  fun toMultimap(): Map<String, List<String>> {
    val result = TreeMap<String, MutableList<String>>(String.CASE_INSENSITIVE_ORDER)
    for (i in 0 until size) {
      val name = name(i).lowercase(Locale.US)

          M extends Multimap<K, V>>
      Collector<T, ?, M> toMultimap(
          java.util.function.Function<? super T, ? extends K> keyFunction,
          java.util.function.Function<? super T, ? extends V> valueFunction,
          java.util.function.Supplier<M> multimapSupplier) {
    return CollectCollectors.<T, K, V, M>toMultimap(keyFunction, valueFunction, multimapSupplier);
  }

  /**

    val values: List<String> = headers.values("")
    val byteCount: Long = headers.byteCount()
    val builder: Headers.Builder = headers.newBuilder()
    val multimap: Map<String, List<String>> = headers.toMultimap()
  }

  @Test
  fun headersBuilder() {
    var builder: Headers.Builder = Headers.Builder()
    builder = builder.add("")
    builder = builder.add("", "")

	public static final fun of (Ljava/util/Map;)Lokhttp3/Headers;
	public static final fun of ([Ljava/lang/String;)Lokhttp3/Headers;
	public final fun size ()I
	public final fun toMultimap ()Ljava/util/Map;
	public fun toString ()Ljava/lang/String;
	public final fun value (I)Ljava/lang/String;
	public final fun values (Ljava/lang/String;)Ljava/util/List;
}