how to Import address book contacts

Hi, I have a web application from where i need to import address book contact of yahoo,google, hotmail. how can I do that? Any suggestion? Please reple.

I don't think there's a single way to do it, but most of the services have their own APIs, and some of them provide Java libraries. See:

Google Contacts Data API

Yahoo! Address Book API

Yahoo! Contacts API

Windows Live Contacts API

Hi,
I came across this website, plaxo.com and linkedln.com in which people can import addressbook. any suggestions?

Those sites probably use the APIs mentioned by Carey.

how can I use those API's?

At the risk of sounding trivial: by reading the documentation and implementing what it says. Or am I misunderstanding your question?

i am trying to use plaxo widget, i am having some difficulties. anyways let me try and will come back to you people.

Thanks

Just for fun... Created a webapp and tried the mentioned APIs. This is how long it took me to do view my contacts.

Google Contacts: 29 minutes (included download).
Windows Live: 44 minutes (had problem with proxy)
Yahoo: 41 minutes (errata in documentation).

No, it is not hard at all.