Datatable with dynamic columns, multiple colums per object - jsf

Question

I have dynamic number of Tests (measurements) for each item (Apple, Banana) and every Test has 2 Properties (mandatory, visible). What I need is table that shows these Tests as columns (colspan=2) and its Properties (colspan=1), like in example below. I can do it for table header (using Primefaces' p:columnGroup) but I don't know how to fill two columns for every Property while iterating through properties list.
Only idea I have is to make new List where every item will exist twice (Diameter, Diameter, Length, Length), iterate over it and use some modulo condition to choose correct property.
My current solution is:
xhtml
<p:dataTable var="scenario">
...
<p:columns var="property" value="#{view.getXTimesProperties()}"
columnIndexVar="index">
<c:set var="test" value="#{view.getTest(scenario, property)}"/>
<c:choose>
<c:when test="${index % 2 == 0}">
<h:outputText value="#{test.mandatory}"/>
</c:when>
<c:when test="${index % 2 == 1}">
<h:outputText value="#{test.visible}"/>
</c:when>
</c:choose>
</p:columns>
</p:dataTable>
and View method is
public List<Property> getXTimesProperties() {
List<Property> list = new ArrayList<>(properties.size() * 2);
for (Property property : properties) {
list.add(property);
list.add(property);
}
return list;
}
Is there a better way? Thanks in advance for better idea!

Answer 1

Yes, better way (credits to Kukeltje):
<p:dataTable var="scenario">
...
<c:forEach var="property" items="#{view.properties}">
<c:set var="test" value="#{view.getTest(scenario, property)}"/>
<p:column>
<h:outputText value="#{test.mandatory}"/>
</p:column>
<p:column>
<h:outputText value="#{test.visible}"/>
</p:column>
</c:forEach>
</p:dataTable>