title: Java 8 Stream API : Filter on instance, and cast
body: <p>I have a list of objects:</p>
  
  <pre><code>List&lt;SomeType&gt; myList;
  </code></pre>
  
  <p>I want to get a list of sub-types available in this list:</p>
  
  <pre><code>List&lt;SomeChildType&gt; myChildList = myList.stream().filter(e -&gt; e instanceof SomeChildType).collect(??????)
  </code></pre>
  
  <p>I don't know how to collect to obtain the correct list type.</p>