I’m looking for a solid Java solution to import contacts
I’m building a web application that needs a friend invitation feature, much like what social media sites offer. When users register on platforms like Facebook or LinkedIn, they often get the option to import their email contacts. I want to create something similar.
The idea is for users to input their email credentials, allowing my app to access and retrieve their contacts from major email services like Gmail, Yahoo, and Outlook. This way, I can display which of their contacts are already on my platform.
I’ve been on the lookout for Java libraries that facilitate the extraction of contacts from emails, but I’m struggling to find reliable options that work well with various providers. Different services seem to have their own unique APIs and authentication processes.
Has anyone tackled this kind of feature? What methods did you apply? I’m particularly keen on discovering libraries that support multiple email providers in a streamlined manner instead of having to write distinct code for each one.
Any recommendations would be greatly appreciated. Thanks!
i totally feel u on this, man! the auth stuff can be super annoying for users. maybe consider a manual import option? sometimes keeping it simple is the way to go, haha.
Skip trying to grab email credentials directly - go with CardDAV instead. Most major providers support it for contact sync, and it’s way more secure than asking for email passwords. Java libraries like Sardine or Milton handle CardDAV connections pretty well. You’ll use app-specific passwords or OAuth tokens instead of user credentials. I built something like this two years ago and it worked much better than email-based methods. Setup instructions can get a bit technical for users, but you dodge the security nightmare of handling email passwords. Google works out of the box, Microsoft needs some tweaking, Yahoo’s support is meh. Also throw in a CSV import option since most email clients export contacts that way anyway.
I built something similar last year and honestly, there’s no good unified library for contact imports in Java. Everyone ends up writing custom code for each provider. Gmail works well with Google’s Contacts API through their Java client - just make sure you handle OAuth2 correctly. Microsoft Graph API handles Outlook contacts fine. Yahoo’s a pain since they killed their old APIs. What worked for me was building a wrapper service that hides all the different provider implementations behind one interface. You can add new providers without breaking existing stuff. The OAuth flows are always messy, but good error handling and clear user messages help a lot. Start with rate limiting and caching early - contact syncing gets expensive fast when you have more users.