title: Implement a generic interface without type parameter
body: <p>Let's say I have an interface <code>A</code> with generic type:</p>
  
  <pre><code>public interface A&lt;T&gt; {
      T getT();
  }
  </code></pre>
  
  <p>and a class <code>B</code> implementing it:</p>
  
  <pre><code>public class B implements A {
      public Integer getT() { return 1; }
  }
  </code></pre>
  
  <p>...but without give it a type parameter.</p>
  
  <p>What happens here? Does the <code>A</code> be infer to <code>A&lt;Integer&gt;</code>? Is it possible to force user to write type parameter with <code>implements</code> statement(like <code>B implements A&lt;Integer&gt;</code>)?</p>