connecting to gmail, hotmail, yahoo etc.

[Farakh khan]

Hello,

I have assignment to login by providing yahoo, gmail, hotmail etc. credentials like facebook or other social media network sites and to import their contacts.

Can you please let me know the logic or idea as to how this could be achieved in java servlet?

Thanks in anticipation

[Pete Nelson]

I would recommend writing adapter classes, based on a common Interface, to login to the various social network & e-mail sites.

http://en.wikipedia.org/wiki/Adapter_pattern

[Rahul Bhawsar]

and you can use OAuth to connect to various sites. Please see the below link for detail
http://oauth.net/code/

[Sherif Shehab]

check Scribe it's an implementation for OAuth