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

        // Cleanup first
        cleanup();
        log.debug("Closing pool");

        // Create a snapshot of connections to close
        List<SmbTransportImpl> toClose = new ArrayList<>(this.connections);
        toClose.addAll(this.nonPooledConnections);

        // Clear the collections (thread-safe operations)
        this.connections.clear();
        this.nonPooledConnections.clear();