M1 Tip#8: Dynamic Property

It's possible to have dynamic properties in Maven. A dynamic property is a property whose name is computed. Here's an example:
<j:set var="dynamicProperty" 
  value="my.dynamic.property.${otherProperty}"/>
<j:if test="${context.getVariable(dynamicProperty) == 'whatever'}">
[...]
Notice that you need to use context.getVariable() to evaluate the property and retrieve its value.