title: javax.persistence.EntityManager.createQuery: when with / when without resultClass
body: <ul>
  <li><code>javax.persistence.EntityManager.createQuery(String qlString)</code></li>
  <li><code>javax.persistence.EntityManager.createQuery(String qlString, Class&lt;ResultType&gt; resultClass)</code></li>
  </ul>
  
  <p>In which cases the <code>qlString</code> is sufficent and in which cases I also need to add the <code>resultClass</code>?</p>
  
  <p>And: what part does the type of the result play in this regard (<code>List&lt;ResultType&gt; result = q.getResultList()</code>) ?</p>