International Flight transfer from Shanghai-Hongqiao Apt (SHA) to Shanghai-Pu Dong Apt (PVG)

I am travelling from India to Japan.
The flight goes from India to Hongqiao and then the next flight to Japan is from Pu Dong.
For the connecting flight I need to travel from Shanghai-Hongqiao Apt (SHA) airport to Shanghai-Pu Dong Apt (PVG) airport.There is a gap of 6 hours between the flights.

How can i travel to the other airport?
Is any visa required?