As many of you know, I operate a number of services that integrate with Twitter, including SuperTweet API and 140plus publisher, along with a number of other apps, webapps, web services, and other projects and sites I'm involved with. Most of these use the excellent Twitter4J Java library by Yusuke Yamamoto.
With the deprecation of the current Twitter API 1.0 by Twitter in September and its shutdown scheduled for March 2013, we were all anxiously anticipating a new version of Twitter4J with support for the Twitter 1.1 API so our projects would be ready for the looming API 1.0 shutdown. And, behold, Twitter4J 3.0.x is now released.
Given the magnitude of the underlying changes, I expected the migration from Twitter4J 2.2.x to 3.0.x to be a bit daunting, I was pleasantly surprised to find that, at least for the projects I've ported so far, it has been extremely painless. The biggest potential issue is probably that all Twitter API 1.1 endpoints including the Search API now require OAuth authorization unlike Twitter API 1.0 and previous versions of Twitter4J. Otherwise, in my case, it was mostly a matter of simply rebuilding the code with the new JAR. There is a migration guide on the Twitter4J site.
I can't recommend Twitter4J highly enough. I suggest you get over to the site and donate. I did.