Twitter Service

We need a 'Twitter Micro Service'. This service will provide intelligent insight into stored tweet data. The foundations of this service are a strong object orientated domain model that is independent of any framework. In order that I can consider to the proposal, examples of basic OOP techniques are required. A Twitter domain model will comprise of a number of classes such as Tweet, User, Hashtag, etc etc. Validation and behaviour on the objects will be needed. I would then like to see a basic REST service using Dropwizard Framework that expose the model. For now, don't worry about integrating the Twitter API. Use dummy data in test fixtures to populate your domain model. I'm mostly interested in style of code at this stage so do just enough work to demonstrate style and please make sure unit tests are included. Please build as a JAR using Maven and submit in proposal. This projects needs to be completed in less than 48 hrs, in order to cosider for more work.