add trim() method to XML (removes #text nodes)

core/src/processing/data/XML.java

@@ -33,6 +33,9 @@ import org.xml.sax.*;
 import javax.xml.transform.*;
 import javax.xml.transform.dom.*;
 import javax.xml.transform.stream.*;
+import javax.xml.xpath.XPathConstants;
+import javax.xml.xpath.XPathExpression;
+import javax.xml.xpath.XPathFactory;
 
 import processing.core.PApplet;
 
@@ -582,6 +585,25 @@ public class XML implements Serializable {
   }
 
 
+  public void trim() {
+    try {
+      XPathFactory xpathFactory = XPathFactory.newInstance();
+      XPathExpression xpathExp =
+        xpathFactory.newXPath().compile("//text()[normalize-space(.) = '']");
+      NodeList emptyTextNodes = (NodeList)
+        xpathExp.evaluate(node, XPathConstants.NODESET);
+
+      // Remove each empty text node from document.
+      for (int i = 0; i < emptyTextNodes.getLength(); i++) {
+        Node emptyTextNode = emptyTextNodes.item(i);
+        emptyTextNode.getParentNode().removeChild(emptyTextNode);
+      }
+    } catch (Exception e) {
+      throw new RuntimeException(e);
+    }
+  }
+
+
 //  /** Remove whitespace nodes. */
 //  public void trim() {
 //////    public static boolean isWhitespace(XML xml) {