title: How do I declare a 2D String arraylist?
body: <p>I want to do something like this <code>ArrayList&lt;String&lt;String&gt;&gt; mylist</code></p>
  
  <p>How can I create it?</p>
  
  <p>How can I add to the external and internal list</p>
  
  <p>and how can I convert the internal list to a simple array list?</p>