XML Parsing Examples with XOM

student_input.xml

<?xml version="1.0"?>
<students>
    <student href="http://first.com">
        <name rel="first">Sriram</name>
        <age>2</age>
    </student>
    <student href="http://second.com">
        <name rel="second">Venkat</name>
        <age>29</age>
    </student>
    <student href="http://third.com">
        <name rel="third">Anu</name>
        <age>28</age>
    </student>
</students>

XomParsing.java

package test.xml;


import java.io.IOException;
import java.io.InputStream;

import nu.xom.Nodes;
import nu.xom.Builder;
import nu.xom.Document;
import nu.xom.Element;
import nu.xom.Elements;
import nu.xom.ParsingException;
import nu.xom.ValidityException;

public class XomParsing {

  /**
   * @param args
   */
  public static void main(String[] args) throws ValidityException, ParsingException, IOException {
    XomParsing p = new XomParsing();

    Builder builder = new Builder();
    InputStream ins = XomParsing.class.getClassLoader().getResourceAsStream("student_input.xml");

    Document doc = builder.build(ins);

    // p.traverse(doc);
    p.applyXpath(doc);
  }


  public void traverse(Document doc) {
    Element root = doc.getRootElement();
    System.out.println("Root Node : " + root.getLocalName());
    
    // Get children
    Elements students = root.getChildElements();
    Element nameChild = null;
    for (int i = 0; i < students.size(); i++) {
      System.out.println(" Child : " + students.get(i).getLocalName());
      
      // Get first child with tag name as 'name'
      nameChild = students.get(i).getFirstChildElement("name");
      if (nameChild != null) {
        System.out.println("  Name : " + nameChild.getValue());
      }
    }
  }

  private void applyXpath(Document doc) {
    Element root = doc.getRootElement();
    Nodes result = root.query("/students/student[name[@rel=\"second\"]]/@href");
    System.out.println(result.get(0).getValue());
  }

}