How can I create a custom tag in JPMML? I'm trying to create a logistic regression model in jpmml, then write the PMML to a file. The problem I'm having, is that I can't find any way to create a custom tag, such as "shortForm" and "longForm" in the following example:

&lt;MapValues outputColumn="longForm"&gt;
  &lt;FieldColumnPair field="gender" column="shortForm"/&gt;
  &lt;InlineTable&gt;
    &lt;row&gt;&lt;shortForm&gt;m&lt;/shortForm&gt;&lt;longForm&gt;male&lt;/longForm&gt;
    &lt;/row&gt;
    &lt;row&gt;&lt;shortForm&gt;f&lt;/shortForm&gt;&lt;longForm&gt;female&lt;/longForm&gt;
    &lt;/row&gt;
  &lt;/InlineTable&gt;
&lt;/MapValues&gt;


Here's what I have so far:

MapValues mv = new MapValues("output")
  .withFieldColumnPairs(
        new FieldColumnPair( new FieldName("gender"), "shortForm" )
  ).withInlineTable(
        new InlineTable().withRows(
                new Row().with???( new ??? )
)))


In short, I am asking for an API call I can use to instantiate the "shortForm" element in the example, and attach it to the "row" object. I've been all through the API, examples, and Google/SO, and can't find a thing. 

Thanks for your help!
You can/should use a generic Java Architecture for XML Binding (JAXB) approach.

Simply put, call Row#withContent(Object...) with instances of org.w3c.dom.Element that represent the desired XML content.

For example:

Document document = documentBuilder.newDocument();
Element shortForm = document.createElement("shortForm");
shortForm.setTextContent("m");
Element longForm = document.createElement("longForm");
longForm.setTextContent("male");
row = row.withContent(shortForm, longForm);