}

    val http2Connection = this.http2Connection
    if (http2Connection != null) {
      return http2Connection.isHealthy(nowNs)
    }

    val idleDurationNs = lock.withLock { nowNs - idleAtNs }
    if (idleDurationNs >= IDLE_CONNECTION_HEALTHY_NS && doExtensiveChecks) {
      return socket.isHealthy(source)
    }

    return true
  }

  /** Refuse incoming streams. */
  @Throws(IOException::class)

    // Make sure this connection is healthy & eligible for new exchanges. If it's no longer needed
    // then we're on the hook to close it.
    val healthy = candidate.isHealthy(connectionUser.doExtensiveHealthChecks())
    var noNewExchangesEvent = false
    val toClose: Socket? =
      candidate.withLock {
        when {
          !healthy -> {

    // When the timeout is sent the connection doesn't immediately go unhealthy.
    assertThat(connection.isHealthy(System.nanoTime())).isTrue()

    // But if the ping doesn't arrive, the connection goes unhealthy.
    Thread.sleep(TimeUnit.NANOSECONDS.toMillis(Http2Connection.DEGRADED_PONG_TIMEOUT_NS.toLong()))
    assertThat(connection.isHealthy(System.nanoTime())).isFalse()

    // When a pong does arrive, the connection becomes healthy again.

              true
            }
          }
        }
      if (!acquired) continue

      // Confirm the connection is healthy and return it.
      if (connection.isHealthy(doExtensiveHealthChecks)) return connection

      // In the second synchronized block, release the unhealthy acquired connection. We're also on
      // the hook to close this connection if it's no longer in use.

        if (isShutdown) {
          throw ConnectionShutdownException()
        }
        okHttpSettings.merge(settings)
      }
      writer.settings(settings)
    }
  }

  fun isHealthy(nowNs: Long): Boolean {
    this.withLock {
      if (isShutdown) return false

      // A degraded pong is overdue.
      if (degradedPongsReceived < degradedPingsSent && nowNs >= degradedPongDeadlineNs) return false