public   static  Element StreamToDOM(Reader reader)
     throws  Exception{
        
        Document document = createDocument();
        Transformer transformer = TransUtils.createTransformer();
        transformer.transform( new  StreamSource(reader),  new  DOMResult(document));
        
         return  document.getDocumentElement();
    }
    
    /**
     * Преобразование строки в DOM модель
     * @param strXML Строка, содержащая xml
     */
     public   static  Element StringToDOM(String strXML)
     throws  Exception{
        
        StringReader strReader =  new  StringReader(strXML);
        Document document = createDocument();
        TransUtils.createTransformer().
                transform( new  StreamSource(strReader),  new  DOMResult(document));
        
         return  document.getDocumentElement();
    }
    
    
    /**
     * Преобразование объекта Element в строку.
     */
     public   static  String DOMToString(Element elem)
     throws  Exception{
        
        StringWriter strWriter= new  StringWriter();
        TransUtils.createTransformer().
                transform( new  DOMSource(elem),  new  StreamResult(strWriter));
        
         return  strWriter.toString();
    }

 class  TransUtils{

 import  java.io.InputStream;
 import  java.io.OutputStream;
 import  javax.xml.transform.Transformer;
 import  javax.xml.transform.TransformerFactory;
 import  javax.xml.transform.stream.StreamSource;
....

/**
     * Создание объекта Transformer без параметров
     */
     public   static  Transformer createTransformer()
     throws  Exception{
        TransformerFactory tFactory=TransformerFactory.newInstance();
        Transformer transformer=tFactory.newTransformer();
        
         return  transformer;
    }
}