title: Drools get first element of List in where clause
body: <p>Is it possible to get first element of list from <strong>when</strong> clause in Drools? 
  If I don't know Object fields values inside the list and I want just to retrieve first element, how can I do this? </p>
  
  <pre><code>rule "TestRule1"
  dialect "java"
  when
      $c : Collection()
      $listCustObjs : ArrayList() from collect (CustomObject() from $c)
  
      $first : $listCustObjs.get(0) //&lt;- something like this
      $otherObj : $first.other // &lt;- take other element from first object from the list
  
  then
     ...
  end;
  </code></pre>