New Gmail API - Quick Start example with details

I need to use the new Gmail API RESTful in a really simple test. I'm trying to start with the quick start example but it just not working!!!

http://ift.tt/WfDA09 !this is how it looks on Eclipse platform]1 I need for an example (from A to Z )in Java on how to sent a message using this Gmail Restful API. I know that this link might be useful but I didn't know how to use it!! How to send a message successfully using the new Gmail REST API? I'm not a professional in Java I'm using Eclipse over Ubuntu. Thanks