This string includes the properties used to enable replica set failover for write operations with no authentication. 

jdbc:datadirect:mongodb://host:port;AuthenticationMethod=None;DatabaseName=database;
     ReplicaSetName=replica_set;[property=value[;...]];

where:

host

specifies the name or the IP address of the MongoDB server to which you want to connect.

For example, myserver.
port

specifies the port number of the server listener. The default is 27017.

database
(optional) specifies the name of the database to which you want to connect. This value is used as the default qualifier for unqualified table names in SQL queries. Required for User/ID password authentication.
Important: This value is case-insensitive if you have access privileges to query the list of databases on the server. If you do not have access, this value is case-sensitive.
replica_set
specifies the name of the replica set against which you want to execute write operations.
property=value
specifies connection property settings. Multiple properties are separated by a semi-colon.

The following example connection string includes the properties used to enable replica set failover for write operations with no authentication: 

Connection conn = DriverManager.getConnection
  ("jdbc:datadirect:mongodb://MongodbServer:27017;AuthenticationMethod=None;
         DatabaseName=Mongodb1;ReplicaSetName=MyReplicaSet;");