title: Error in retrieving the size of an array list
body: <p>I am creating an application which retrieve from an external party application an arraylist of Integer values. It seems that some of the elements in this retrieved list are empty or null. When I retrieve the size of the list for example:</p>
  
  <pre><code>System.out.println("The number of elements is : "+ elements_list.size());
  </code></pre>
  
  <p>it just throws an null pointer exception. Does anyone know a solution for such a problem? Thanks in advance!</p>