Copying a Subtree of Nodes from One DOM Document to Another : DOM Tree « XML « Java Tutorial

1. Java Tutorial
2. XML
3. DOM Tree

import java.io.File;

import javax.xml.parsers.DocumentBuilderFactory;

import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;

public class Main {
  public static void main(String[] argv) throws Exception {
    DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
    factory.setValidating(true);

    factory.setExpandEntityReferences(false);

    Document doc1 = factory.newDocumentBuilder().parse(new File("filename"));
    NodeList list = doc1.getElementsByTagName("entry");
    Element element = (Element) list.item(0);

    Document doc2 = factory.newDocumentBuilder().parse(new File("infilename2.xml"));

    Node dup = doc2.importNode(element, true);

    doc2.getDocumentElement().appendChild(dup);
  }
}