In enterprise/jbiTester subcomponent, there is a requirement to use XDM for
pretty print and diff of XML. I set this priority to P2 as the dependent
jbiTester issue needs to be resolved for FCS. 

Discussed with Ayub through email and then create this issue. Below are the
discussion of items.

 1. public static String prettyPrintXML(String doc, String indentation){ }

 2.
 /*
 type is the comparison type - currently only equal, identical. */ 
 public static List<XMLUtil.Difference> compareXML(String firstDoc,  String
secondDoc, type) { };

 3. create XMLUtil classese that are used in showDiff() sample code that 
 support for locating the difference.

 public void showDiff(javax.swing.Document doc1, javax.swing.Document
 doc2) { //illustrating how to find xml difference and display in ui
    String xmlstring1 = doc1.getText(0, doc1.getLength());
    String xmlstring2 = doc2.getText(0, doc1.getLength());
    XMLUtil.DiffInfo diffInfo = XMLUtil.findDiff(xmlstring1, 
 xmlstring2); //diffInfo is an object that holds onto the internal 
 representation.
    List<XMLUtil.Difference> diffs = diffInfo.getDifferences(); 
 //returns the difference
    for(XMLUtil.Difference diff: diffs) {
       XMLUtil.OldNodeInfo oldInfo = diff.getOldNodeInfo();
       XMLUtil.NewNodeInfo oldInfo = diff.getNewNodeInfo();
       if(oldInfo  != null ) {
         XMLUtil.Position p1 = diffInfo.findPosition(oldInfo.getNode());
         //AttributeSet could indicate a different color for Add, 
 Delete, Change
         ((StyledDocument)doc1).setCharacterAttributes(p1.getBegin, 
 p1.getEnd()-p1.getBegin, AttributeSet s, true);             }
       if(oldInfo  != null ) {
         XMLUtil.Position p1 = diffInfo.findPosition(oldInfo.getNode());
         //AttributeSet could indicate a different color for Add, 
 Delete, Change
         ((StyledDocument)doc1).setCharacterAttributes(p1.getBegin, 
 p1.getEnd()-p1.getBegin, AttributeSet s, true);             }
    }
 }