DataFieldResolver dataFieldResolver = new GraphNodeDataFieldResolver(node, simpleFunctions);
StringReader reader = new StringReader("${ns:rdfs=http://www.w3.org/2000/01/rdf-schema#}${if rdfs:comment}yes${/if} and ${if rdfs:label}yes${else}no${/if}");
StringWriter writer = new StringWriter();
new DefaultParser(reader, writer).perform(dataFieldResolver);
Assert.assertEquals("yes and no", writer.toString());
}