s defined as followed:
     <ul>
         <li>if the XML configuration defines a provider, this provider is used</li>
         <li>if the XML configuration does not define a provider or if no XML
         configuration is present the first provider returned by the
         <a href="../../javax/validation/ValidationProviderResolver.html" title="interface in javax.validation"><code>ValidationProviderResolver</code></a> instance is used.</li>
     </ul>
     </li>
     <li>
     The second bootstrap approach a