public JsonNode transform(String json) {
			try {
				return mapper.readTree(json);
			}
			catch (JsonParseException e) {
				throw new MessageTransformationException("unable to parse input: " + e.getMessage(), e);
			}
			catch (IOException e) {
				throw new MessageTransformationException("unable to create json parser: " + e.getMessage(), e);
			}
		}
@author David Turanski
@author Gary Russell
spring-xd-analytics/src/test/java/org/springframework/xd/analytics/metrics/integration/RichGaugeHandlerTests.java