Timeouts experienced after connecting to MongoDB

I am trying to connect to Mongodb from Ready API using Java driver.

I followed the steps from

https://smartbear-cc.force.com/portal/KbArticleViewer?name=How-to-connect-to-MongoDB-from-ReadyAPI-using-MongoDB-Java-Driver&sp=all

and installed the necessary jars and followed the code given.

I am getting com.mongodb.MongoTimeoutException: Timed out after 30000 ms while waiting to connect. Client view of cluster state is {type=UNKNOWN, servers=[{address=mongodb server address, type=UNKNOWN, state=CONNECTING, exception={com.mongodb.MongoSocketReadException: Prematurely reached end of stream}}] error at line: 17

Need help in troubleshooting.