Refactoring, New XPath methods

Varianten/AdapterFIDEROS/src/Adapter.java

@@ -18,35 +18,61 @@ import org.jdom2.xpath.*;
 public class Adapter {
 	
 	/**
-	 * Searches a document for the first occurrence of an xml tag using XPath.
+	 * Executes given XPath expression for elements.
 	 * 
 	 * @param doc			The JDOM Document
-	 * @param elementName	Name of the xml tag
-	 * @return First element found or NULL if no match found
+	 * @param xPath			XPath expression
+	 * @return List with all elements found or empty list if no match found
 	 */
-	public static Element queryFirstElement(Document doc, String elementName) {
+	public static List<Element> xQueryElements(Document doc, String xPath) {
 		XPathFactory xFactory = XPathFactory.instance();
-		XPathExpression<Element> expr = xFactory.compile("//"+elementName, Filters.element());
-		Element result = expr.evaluateFirst(doc);
+		XPathExpression<Element> expr = xFactory.compile(xPath, Filters.element());
+		List<Element> result = expr.evaluate(doc);
 		
 		return result;
 	}
 	
 	/**
-	 * Searches a document for all occurrences of an xml tag using XPath.
+	 * Executes given XPath expression for attributes.
 	 * 
 	 * @param doc			The JDOM Document
-	 * @param elementName	Name of the xml tag
-	 * @return List with all elements found or empty List if no match found
+	 * @param xPath			XPath expression
+	 * @return List with all attributes found or empty list if no match found
 	 */
-	public static List<Element> queryAllElements(Document doc, String elementName) {
+	public static List<Attribute> xQueryAttributes(Document doc, String xPath) {
 		XPathFactory xFactory = XPathFactory.instance();
-		XPathExpression<Element> expr = xFactory.compile("//"+elementName, Filters.element());
-		List<Element> result = expr.evaluate(doc);
+		XPathExpression<Attribute> expr = xFactory.compile(xPath, Filters.attribute());
+		List<Attribute> result = expr.evaluate(doc);
 		
 		return result;
 	}
-
+	
+	/**
+	 * Searches a document for the first occurrence of an xml tag.
+	 * 
+	 * @param doc			The JDOM Document
+	 * @param elementName	Name of the xml tag
+	 * @return First element found or NULL if no match found
+	 */
+	public static Element searchFirstElement(Document doc, String elementName) {
+		//XPath index starts with 1; [] has a higher precedence than //
+		List<Element> query= xQueryElements(doc, "(//"+elementName+")[1]");
+		
+		if(query.isEmpty()) return null;
+		return query.get(0);
+	}
+	
+	/**
+	 * Searches a document for all occurrences of an xml tag.
+	 * 
+	 * @param doc			The JDOM Document
+	 * @param elementName	Name of the xml tag
+	 * @return List with all elements found or empty list if no match found
+	 */
+	public static List<Element> searchAllElements(Document doc, String elementName) {
+		return xQueryElements(doc, "//"+elementName);
+	}
+	
 	/**
 	 * @param args
 	 */
@@ -62,34 +88,46 @@ public class Adapter {
 			//######### Operate on featuremodel.xml #########
 			Element fmRoot = FeatureModel.getRootElement();
 			List<Element> modules = fmRoot.getChildren("module");
+			
 			//###############################################
 			
+			
 			//TODO
 			//######### Operate on .gazebo.xacro ############
 			Element gmRoot = GazeboModel.getRootElement();
-			
-			//XPathExamples
-			XPathFactory xFactory = XPathFactory.instance();
-			XPathExpression<Element> expr = xFactory.compile("robot/gazebo/sensor/ray/range/min", Filters.element());
-			Element test = expr.evaluateFirst(GazeboModel);
-			List<Element> test2 = queryAllElements(GazeboModel, "min");
-			List<Element> test3 = queryAllElements(GazeboModel, "max");
+
 			//###############################################
 			
 			
 			FileOutputStream dest = new FileOutputStream("resources/output/turtlebot3_burger.gazebo.xacro");
 			XMLOutputter xmlOutput = new XMLOutputter();
+			
 			//TODO
 			//######### Output result #######################
 			xmlOutput.output(GazeboModel, dest);
+
+			//###############################################
+			
 			
 			//XPathExamples
+			XPathFactory xFactory = XPathFactory.instance();
+			XPathExpression<Element> xExpr = xFactory.compile("robot/gazebo/sensor/ray/range/min", Filters.element());
+			Element test = xExpr.evaluateFirst(GazeboModel);
+			List<Element> test2 = searchAllElements(GazeboModel, "min");
+			List<Element> test3 = searchAllElements(GazeboModel, "max");
+			Element test4 = searchFirstElement(GazeboModel, "plugin");
+			List<Attribute> test5 = xQueryAttributes(GazeboModel, "(//plugin)[1]/@*");
+			
 			if(test != null) xmlOutput.output(test, System.out);
-			System.out.println();
+			System.out.println("\n");
 			xmlOutput.output(test2, System.out);
-			System.out.println();
+			System.out.println("\n");
 			xmlOutput.output(test3, System.out);
-			//###############################################
+			System.out.println("\n");
+			if(test4 != null) xmlOutput.output(test4, System.out);
+			System.out.println("\n");
+			for(Attribute a : test5) System.out.println(a.getName()+"="+a.getValue());
+			
 		} catch (JDOMException | IOException e) {
 			e.printStackTrace();
 		}