using GT utility classes for XML parsing/producing

Author: pmauduit

geowebcache/core/src/main/java/org/geowebcache/config/XMLConfiguration.java

@@ -54,6 +54,7 @@
 import javax.xml.validation.SchemaFactory;
 import javax.xml.validation.Validator;
 import org.geotools.util.logging.Logging;
+import org.geotools.xml.XMLUtils;
 import org.geowebcache.GeoWebCacheEnvironment;
 import org.geowebcache.GeoWebCacheException;
 import org.geowebcache.GeoWebCacheExtensions;
@@ -616,7 +617,7 @@ static Node loadDocument(InputStream xmlFile) throws ConfigurationException, IOE
         try {
             DocumentBuilderFactory docBuilderFactory = DocumentBuilderFactory.newInstance();
             docBuilderFactory.setNamespaceAware(true);
-            DocumentBuilder docBuilder = docBuilderFactory.newDocumentBuilder();
+            DocumentBuilder docBuilder = XMLUtils.newDocumentBuilder(docBuilderFactory);
             topNode = checkAndTransform(docBuilder.parse(xmlFile));
         } catch (Exception e) {
             throw (IOException) new IOException(e.getMessage()).initCause(e);
@@ -758,7 +759,7 @@ static String getCurrentSchemaVersion() {
 
         Document dom;
         try (InputStream is = XMLConfiguration.class.getResourceAsStream("geowebcache.xsd")) {
-            dom = DocumentBuilderFactory.newInstance().newDocumentBuilder().parse(is);
+            dom = XMLUtils.newDocumentBuilder().parse(is);
         } catch (Exception e) {
             throw new RuntimeException(e);
         }
@@ -777,7 +778,7 @@ private static Node applyTransform(Node oldRootNode, String xslFilename) {
         try (InputStream is = XMLConfiguration.class.getResourceAsStream(xslFilename)) {
 
             try {
-                transformer = TransformerFactory.newInstance().newTransformer(new StreamSource(is));
+                transformer = XMLUtils.newTransformer(new StreamSource(is));
                 transformer.transform(new DOMSource(oldRootNode), result);
             } catch (TransformerFactoryConfigurationError | TransformerException e) {
                 log.log(Level.FINE, e.getMessage(), e);