title: How to split element in an ArrayList in multidimensional arrayList
body: <p>I have the following:</p>
  
  <pre><code>[[Statistics (pH)], [ Upright Normal Recumbent Normal Total]]
  </code></pre>
  
  <p>I want to split the first element of the second element on whitespace so that I end up with:</p>
  
  <pre><code>[[Statistics (pH)], [Upright,Normal,Recumbent,Normal,Total]]
  </code></pre>
  
  <p>My code so far:</p>
  
  <pre><code>for (ArrayList&lt;List&lt;String&gt;&gt; row2 : StatspH) {
  row2.get(1).get(0).split("\\s");
  }
  </code></pre>
  
  <p>but nothing happens</p>