Java Clone Example,Java Clone Tutorial,Cloning the XML Element

Cloning a XML Element

In this section, you will learn to create a clone of a element in the DOM tree. In general, the cloning means to create a duplicate.

Description of a program:

The following program helps you in creating a clone of any element of the specified XML file. For creating a DOM object , you need the DocumentBuilderFactoty and the DocumentBuilder objects. After parsing it displays a xml file on the console using the transform() method. At run time the program asks for a element name to clone . Here the

element1.cloneNode(true) method
creates a clone and element1.getParentNode().insertBefore(copyElement, element1.getNextSibling())
inserts the clone element at the specified position.

<?xml version = "1.0" ?>
<Employee-Detail>
<Employee>
<Emp_Id> E-001 </Emp_Id>
<Emp_Name> Vinod </Emp_Name>
<Emp_E-mail> Vinod1@yahoo.com </Emp_E-mail>
</Employee>
</Employee-Detail>


import java.io.*;

import org.w3c.dom.*;

import org.xml.sax.*;

import javax.xml.parsers.*;

import javax.xml.transform.*; 

import javax.xml.transform.dom.DOMSource; 

import javax.xml.transform.stream.StreamResult;



public class DOMCloneElements {

  static public void main(String[] arg){

    try  {

      BufferedReader bf = new BufferedReader(new InputStreamReader(System.in));

      System.out.print("Enter XML file name: ");

      String xmlFile = bf.readLine();

      File file = new File(xmlFile);

      if (file.exists()){

        DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();

        DocumentBuilder builder = factory.newDocumentBuilder();

        Document doc = builder.parse(xmlFile);

        TransformerFactory tFactory = TransformerFactory.newInstance();

        Transformer tformer = tFactory.newTransformer();

        Source source = new DOMSource(doc);

        Result result = new StreamResult(System.out);

        System.out.println(xmlFile + " file: ");

        tformer.transform(source, result);

        System.out.println();

        System.out.print("Enter the element to clone: ");

        String clone = bf.readLine();

        System.out.print("Enter data to add: ");

        String addElement = bf.readLine();

        ////////////////////////////////

        NodeList list = doc.getElementsByTagName(clone);

        Element element1 = (Element)list.item(0);

        Element copyElement = (Element) element1.cloneNode(true);

        element1.getParentNode().insertBefore(copyElement, 

                                 
element1.getNextSibling());

        element1.appendChild(doc.createTextNode(addElement));

        tformer.transform(source, result);

      }

      else{

        System.out.println("File not found!");

      }

    }

    catch (Exception e){

      e.getMessage();

    }

  }

}

Output of this program:

C:\vinod\xml>javac DOMCloneElements.java

C:\vinod\xml>java DOMCloneElements
Enter XML file name: Employee-Detail2.xml
Employee-Detail2.xml file:
<?xml version="1.0" encoding="UTF-8" standalone="no"?><Employee-Detail>
<Employee>
<Emp_Id> E-001 </Emp_Id>
<Emp_Name> Vinod </Emp_Name>
<Emp_E-mail> Vinod1@yahoo.com </Emp_E-mail>
</Employee>
</Employee-Detail>
Enter the element to clone: Emp_Id
Enter data to add: E011
<?xml version="1.0" encoding="UTF-8" standalone="no"?><Employee-Detail>
<Employee>
<Emp_Id> E-001 E011</Emp_Id><Emp_Id> E-001 </Emp_Id>
<Emp_Name> Vinod </Emp_Name>
<Emp_E-mail> Vinod1@yahoo.com </Emp_E-mail>
</Employee>
</Employee-Detail>