title: Implementing a interface and extending an class that implements the same interface?
body: <p>Can implementing a interface and extending an class that implements the same interface cause any problems? (other than confusion)</p>
  
  <p>For example:</p>
  
  <pre><code>interface IDo
  public abstract class DoIt implements IDo
  public class IllDo extends DoIt implements IDo
  </code></pre>
  
  <p>(please ignore that it just seems wrong)</p>