title: Why would you use a generic type specifier when extending a Java class?
body: <p>I just wonder what usage the following code has:</p>
  
  <pre><code>public class Sub extends java.util.ArrayList&lt;String&gt; {...}
  </code></pre>
  
  <p>There is no any compiling restriction on the generic constraint <code>java.util.ArrayList&lt;String&gt;</code>.</p>