Remote Method Invocation is required for any client to connect to a server and execute server's methods. As Virtual DataPort server enables connecting from various JDBC clients, the JDBC driver is developed based on RMI.
I would use the JDBC drivers available at <DENODO_HOME>/tools/client-drivers/jdbc in order to connect to Virtual DataPort server from any of the JDBC clients.
You can refer to '[Access through JDBC](https://community.denodo.com/docs/html/browse/6.0/vdp/developer/access_through_jdbc/access_through_jdbc)' section of Virtual DataPort Developer guide for more information.
Hope this helps!