title: Filter Null items in Stream
body: <p>When using a Java Stream, sometimes null values can occur after mapping. Currently when these values need to be omitted, I use:</p>
  
  <pre><code>.stream()
  .&lt;other operations...&gt;
  .filter(element -&gt; element != null)
  .&lt;other operations...&gt;
  </code></pre>
  
  <p>For a more functional style a tiny helper method is quickly written:</p>
  
  <pre><code>public static &lt;T&gt; boolean nonNull(T entity) {
      return entity != null;
  }
  </code></pre>
  
  <p>So that you can use a method reference instead:</p>
  
  <pre><code>.stream()
  .&lt;other operations...&gt;
  .filter(Elements::nonNull)
  .&lt;other operations...&gt;
  </code></pre>
  
  <p>I could not find such a jdk method, even though I would suspect they have included one. Is there a different approach here? Or did they omit this for a reason?</p>