val connection = this.connection
    if (connection != null) {
      connection.lock.assertNotHeld()
      val toClose: Socket? =
        connection.withLock {
          // Sets this.connection to null.
          releaseConnectionNoEvents()
        }
      if (this.connection == null) {
        toClose?.closeQuietly()
        eventListener.connectionReleased(this, connection)

    if (connectionUser.candidateConnection() != null) {
      check(toClose == null)
      return ReusePlan(candidate)
    }

    // The call's connection was released.
    toClose?.closeQuietly()
    connectionUser.connectionReleased(candidate)
    connectionUser.connectionConnectionReleased(candidate)
    if (toClose != null) {
      connectionUser.connectionConnectionClosed(candidate)

      val noNewExchangesEvent: Boolean
      val toClose: Socket? =
        connection.withLock {
          noNewExchangesEvent = !connection.noNewExchanges
          connection.noNewExchanges = true
          connectionUser.releaseConnectionNoEvents()
        }
      if (toClose != null) {
        toClose.closeQuietly()
        connectionListener.connectionClosed(connection)