I am learning android. In my StatusActivity.java file , I am getting the below error :
Twitter twitter = new Twitter("username", "password");

I have imported the latest jtwitter jar jtwitter-2.9.0.zip and imported the same to project build path.

I am not sure why I am not getting an option to import the required class
It seems that you are using a zipped file instead of jtwitter jar. This is why the jtwitter library classes aren't accessible.
Remove jtwitter-2.9.0.zip - yamba > Unzip this file > Extract jtwitter.jar > Add this jar to your project.
winterwell.jtwitter.Twitter should be available now.