title: MULE 4 - is there a way to check if an XML file contains just one document?
body: <p>I have an input XML file (person.xml), to make it simple:</p>
  <pre><code>&lt;person&gt;
      &lt;name&gt;John&lt;/name&gt;
      &lt;surname&gt;Doe&gt;&lt;/surname&gt;
  &lt;/person&gt;
  </code></pre>
  <p>Is there a way to check if the file <code>person.xml</code> contains one and only one entry, just the one above?</p>
  <p>An example of a <strong>WRONG</strong> file:</p>
  <pre><code>&lt;person&gt;
      &lt;name&gt;John&lt;/name&gt;
      &lt;surname&gt;Doe&gt;&lt;/surname&gt;
  &lt;/person&gt;
  &lt;person&gt;
      &lt;name&gt;Jane&lt;/name&gt;
      &lt;surname&gt;Walker&lt;/surname&gt;
  &lt;/person&gt;
  </code></pre>
  <p>A proper document should have only one person in it.</p>
  <p>Can I achieve this without using Java?</p>