if (tags.isNotEmpty()) {
            (tags as MutableMap).remove(type)
          }
        } else {
          val mutableTags =
            when {
              tags.isEmpty() -> mutableMapOf<KClass<*>, Any>().also { tags = it }
              else -> tags as MutableMap<KClass<*>, Any>
            }
          mutableTags[type] = type.cast(tag)
        }
      }

  fun testLoggingLevels() {
    enableTls()

    val testHandler =
      object : Handler() {
        val calls = mutableMapOf<String, AtomicInteger>()

        override fun publish(record: LogRecord) {
          calls
            .getOrPut(record.loggerName) { AtomicInteger(0) }
            .incrementAndGet()
        }

  internal val client: Boolean = builder.client

  /** User code to run in response to incoming streams or settings. */
  internal val listener: Listener = builder.listener
  internal val streams = mutableMapOf<Int, Http2Stream>()
  internal val connectionName: String = builder.connectionName
  internal var lastGoodStreamId = 0

  /** http://tools.ietf.org/html/draft-ietf-httpbis-http2-17#section-5.1.1 */