In this example you can see how we can read xml attribute value as an integer value instead of string. JDOM provides method such as getIntValue(), getLongValue(), getFloatValue(), getDoubleValue() to get numerical values. For boolean value we can use the getBooleanValue() method.

package org.kodejava.jdom;

import org.jdom2.Document;
import org.jdom2.Element;
import org.jdom2.JDOMException;
import org.jdom2.input.SAXBuilder;

import java.io.IOException;
import java.io.StringReader;

public class JDOMIntegerAttributeValue {
    public static void main(String[] args) {
        String xml = """
                <root>
                    <table width="100"/>
                </root>""";

        SAXBuilder builder = new SAXBuilder();
        try {
            Document document = builder.build(new StringReader(xml));

            Element child = document.getRootElement().getChild("table");
            int tableWidth = child.getAttribute("width").getIntValue();
            System.out.println("tableWidth = " + tableWidth);
        } catch (JDOMException | IOException e) {
            e.printStackTrace();
        }
    }
}

Maven Dependencies

<dependency>
    <groupId>org.jdom</groupId>
    <artifactId>jdom2</artifactId>
    <version>2.0.6.1</version>
</dependency>

The List returned by the getChildren() method call is a java.util.List. Any modification to the List object immediately reflected in the backing document. This make the manipulation of the XML document easy.

You can also see how we can add a new Element to the document by calling the addContent() method.

package org.kodejava.jdom;

import org.jdom2.Document;
import org.jdom2.Element;
import org.jdom2.JDOMException;
import org.jdom2.input.SAXBuilder;
import org.jdom2.output.Format;
import org.jdom2.output.XMLOutputter;

import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.util.List;

public class JDOMAddRemoveElement {
    public static void main(String[] args) {
        String xml = """
                <root>
                    <user name="Alice" age="21" dob="20-01-1988"/>
                    <user name="Bob" age="23" dob="01-05-1986"/>
                </root>""";

        SAXBuilder builder = new SAXBuilder();
        try {
            Document document = builder.build(
                    new ByteArrayInputStream(xml.getBytes()));

            // Adding a new element to the root of the document using the
            // addContent method.
            document.getRootElement().addContent(
                    new Element("people").setAttribute("id", "1"));
            document.getRootElement().addContent(
                    new Element("people").setAttribute("id", "1"));

            // Add a new element. By adding a new element to the List of
            // children we can modify the xml document. Using
            // java.util.List makes the modification of XML document 
            // simple and easy.
            List<Element> children = document.getRootElement().getChildren();
            children.add(new Element("user")
                    .setAttribute("name", "Carol")
                    .setAttribute("age", "25")
                    .setAttribute("dob", "06-03-1984"));

            // Add element to the beginning of the xml document.
            children.add(0, new Element("user")
                    .setAttribute("name", "Jimmy")
                    .setAttribute("age", "25")
                    .setAttribute("dob", "16-05-1984"));

            // Remove the fourth element.
            children.remove(3);

            XMLOutputter outputter =
                    new XMLOutputter(Format.getPrettyFormat());
            outputter.output(document, System.out);
        } catch (JDOMException | IOException e) {
            e.printStackTrace();
        }
    }
}

The result of this code is:

<?xml version="1.0" encoding="UTF-8"?>
<root>
    <user name="Jimmy" age="25" dob="16-05-1984" />
    <user name="Alice" age="21" dob="20-01-1988" />
    <user name="Bob" age="23" dob="01-05-1986" />
    <people id="1" />
    <user name="Carol" age="25" dob="06-03-1984" />
</root>

Maven Dependencies

<dependency>
    <groupId>org.jdom</groupId>
    <artifactId>jdom2</artifactId>
    <version>2.0.6.1</version>
</dependency>

package org.kodejava.jdom;

import org.jdom2.Document;
import org.jdom2.Element;
import org.jdom2.JDOMException;
import org.jdom2.input.SAXBuilder;

import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.text.MessageFormat;
import java.util.List;

public class JDOMTraversingElement {
    public static void main(String[] args) {
        String xml = """
                <root>
                    <country name="Japan" capital="Tokyo"/>
                    <country name="France" capital="Paris"/>
                    <country name="Italy" capital="Rome"/>
                    <country name="England" capital="London"/>
                    <country name="Indonesia" capital="Jakarta"/>
                    <city name="Denpasar"/>
                    <city name="Bangkok"/>
                    <city name="Mumbai"/>
                    <city name="Delhi"/>
                </root>""";

        SAXBuilder builder = new SAXBuilder();
        try {
            Document document = builder.build(
                    new ByteArrayInputStream(xml.getBytes()));

            // Getting the root element
            Element root = document.getRootElement();

            // Getting the first child
            Element country = root.getChild("country");
            System.out.println("Name: " + country.getAttribute("name")
                    .getValue());
            System.out.println("Capital: " + country.getAttribute("capital")
                    .getValue());
            System.out.println("----------------------------------------");

            // Getting all children of the root
            List<Element> elements = root.getChildren();
            for (Element element : elements) {
                if (element.getName().equals("country")) {
                    System.out.println(MessageFormat.format("{0} -> {1}",
                            element.getAttribute("name").getValue(),
                            element.getAttribute("capital").getValue()));
                } else if (element.getName().equals("city")) {
                    System.out.println(element.getAttribute("name")
                            .getValue());
                }
            }
            System.out.println("----------------------------------------");

            // Getting all children of the root named city
            List<Element> cities = root.getChildren("city");
            for (Element city : cities) {
                System.out.println(city.getAttribute("name").getValue());
            }
        } catch (JDOMException | IOException e) {
            e.printStackTrace();
        }
    }
}

The result of the code snippet are:

Name: Japan
Capital: Tokyo
----------------------------------------
Japan -> Tokyo
France -> Paris
Italy -> Rome
England -> London
Indonesia -> Jakarta
Denpasar
Bangkok
Mumbai
Delhi
----------------------------------------
Denpasar
Bangkok
Mumbai
Delhi

Maven Dependencies

<dependency>
    <groupId>org.jdom</groupId>
    <artifactId>jdom2</artifactId>
    <version>2.0.6.1</version>
</dependency>

The following example shows you how to remove attributes from an XML element. We will remove attribute named userid from the <row> element. To remove an attribute you can call the removeAttribute(String name) method of the Element object.

package org.kodejava.jdom;

import org.jdom2.Document;
import org.jdom2.Element;
import org.jdom2.input.SAXBuilder;
import org.jdom2.output.Format;
import org.jdom2.output.XMLOutputter;

import java.io.File;

public class JDOMRemoveAttribute {
    public static void main(String[] args) {
        SAXBuilder builder = new SAXBuilder();
        try {
            // <?xml version="1.0" encoding="UTF-8"?>
            // <root>
            //     <row userid="alice">
            //         <firstname>Alice</firstname>
            //         <lastname>Starbuzz</lastname>
            //     </row>
            // </root>
            Document doc = builder.build(new File("data.xml"));
            XMLOutputter out = new XMLOutputter(Format.getPrettyFormat());
            out.output(doc, System.out);

            // Get the root element and find a child named row and remove
            // its attribute named "userid"
            Element root = doc.getRootElement();
            root.getChild("row").removeAttribute("userid");
            out.output(doc, System.out);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

The program will output the following result to the console:

<?xml version="1.0" encoding="UTF-8"?>
<data>
  <row>
    <username>alice</username>
    <password>secret</password>
  </row>
</data>

<?xml version="1.0" encoding="UTF-8"?>
<data>
  <row>
    <username>alice</username>
    <password>secret</password>
  </row>
</data>

Maven Dependencies

<dependency>
    <groupId>org.jdom</groupId>
    <artifactId>jdom2</artifactId>
    <version>2.0.6.1</version>
</dependency>

This example show you how to remove an element from XML document. In the code snippet below we start by loading an XML document and display its original contents. After that we find the element <row>, and remove the <address> element from it. To get the first child we are using the getChild() method from the root Element object. To remove an element we use the removeChild() method.

package org.kodejava.jdom;

import org.jdom2.Document;
import org.jdom2.input.SAXBuilder;
import org.jdom2.output.Format;
import org.jdom2.output.XMLOutputter;

import java.io.File;

public class JDOMRemoveElement {
    public static void main(String[] args) {
        SAXBuilder builder = new SAXBuilder();
        try {
            Document doc = builder.build(new File("userinfo.xml"));

            // The lines below output the original userinfo.xml content
            //
            // <?xml version="1.0" encoding="UTF-8"?>
            // <rows>
            //   <row>
            //     <firstname>Alice</firstname>
            //     <lastname>Mallory</lastname>
            //     <address>Sunset Road</address>
            //   </row>
            // </rows>
            XMLOutputter out = new XMLOutputter(Format.getPrettyFormat());
            out.output(doc, System.out);

            // Remove the address element from Alice information. First we
            // get the row element from the root element, and finally 
            // remove the address from the row. And the result will be:
            //
            // <?xml version="1.0" encoding="UTF-8"?>
            // <rows>
            //   <row>
            //     <firstname>Alice</firstname>
            //     <lastname>Mallory</lastname>
            //   </row>
            // </rows>
            doc.getRootElement().getChild("row").removeChild("address");
            out.output(doc, System.out);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

The code snippet print the following output:

<?xml version="1.0" encoding="UTF-8"?>
<rows>
  <row>
    <firstname>Alice</firstname>
    <lastname>Starbuzz</lastname>
    <address>Sunset Road</address>
  </row>
</rows>

<?xml version="1.0" encoding="UTF-8"?>
<rows>
  <row>
    <firstname>Alice</firstname>
    <lastname>Starbuzz</lastname>
  </row>
</rows>

Maven Dependencies

<dependency>
    <groupId>org.jdom</groupId>
    <artifactId>jdom2</artifactId>
    <version>2.0.6.1</version>
</dependency>