@Override
        public String toString() {
            return "CompiledXPathFilter{" +
                   "xPathFilter=" + xPathFilter +
                   ", xPathExpression=" + xPathExpression +
                   '}';
        }
@return value as a string, trimmed and, if ignoreCase is true, converted to lower case
stroom-pipeline/src/main/java/stroom/pipeline/filter/SAXEventRecorder.java