if (compiledXPath == null) {
compiledXPath = new AXIOMXPath(source);
}
result = compiledXPath.evaluate(envelope);
} catch (JaxenException e) {
throw new EvaluatorException("Error while parsing the XPath expression: " + source, e);
}
if (result instanceof List) {
List list = (List) result;
if (list.size() == 1 && list.get(0) == null) {