code: private void configureJMXetricAgent() throws XPathExpressionException,
  			Exception {
  		// Gets the config for the samplers
  		NodeList samples = getXmlNodeList("/jmxetric-config/sample",
  				inputSource);
  		for (int i = 0; i < samples.getLength(); i++) {
  			Node sample = samples.item(i);
  			MBeanSampler mbSampler = makeMBeanSampler(sample);
  			agent.addSampler(mbSampler);
  		}
  	}
docs: Use the XML source to configure the agent. Source is read for <sample>
  nodes, each node corresponds to a MBeanSampler to be added to the agent.
  
  @throws XPathExpressionException
  @throws Exception