fix execution-environment in MANIFEST

META-INF/MANIFEST.MF

@@ -2,7 +2,7 @@ Manifest-Version: 1.0
 Bundle-SymbolicName: com.realdolmen.dynatrace.restmonitor;singleton:=t
  rue
 Bundle-Name: REST Monitor
-Bundle-Version: 1.0.0
+Bundle-Version: 1.2.0
 Bundle-ClassPath: .,lib/json-smart-2.2.1.jar,lib/slf4j-api-1.7.16.jar,lib/asm-5.0.3.jar,lib/json-path-2.2.0.jar,lib/accessors-smart-1.1.jar
 Require-Bundle: com.dynatrace.diagnostics.sdk,
  com.dynatrace.diagnostics.httpclient,com.dynatrace.diagnostics.util
@@ -11,4 +11,3 @@ Bundle-Vendor: Realdolmen
 Bundle-Localization: plugin
 Built-By: builduser
 Implementation-Version: 6.5.0.1289
-Bundle-RequiredExecutionEnvironment: JavaSE-1.8

src/com/realdolmen/dynatrace/restmonitor/MeasureCapturedValues.java

@@ -34,6 +34,7 @@ public class MeasureCapturedValues {
 	private static final String PARAM_CONVERSIONMAP = "conversionMap";
 
 	private static final Logger log = Logger.getLogger(RestMonitor.class.getName());
+	private static final String DEFAULT_RESULT = "0.0";
 
 	private MonitorEnvironment monitorEnvironment;
 
@@ -166,14 +167,17 @@ Double extractXPathValue(String xmlBody, String xPathExpression, Map<String, Dou
 		InputSource inputSource = new InputSource( new StringReader(xmlBody));
 		XPathFactory xPathfactory = XPathFactory.newInstance();
 		XPath xpath = xPathfactory.newXPath();
-		String result = "0.0";
+		String result = DEFAULT_RESULT;
 		try {
 			XPathExpression expr = xpath.compile(xPathExpression);
 			result = expr.evaluate(inputSource);
 		} catch (XPathExpressionException e) {
 			throw new RestMonitorConfigurationException("XPath Expression error: " + e.getMessage(), e);
 		}
 		if (conversionMap == null){
+			if (result==null || result.length()==0){
+				result = DEFAULT_RESULT;
+			}
 			try {
 				return Double.parseDouble(result);
 			}