This example demonstrate how to convert JDOM Document object to a String using the XMLOutputter.outputString(Document doc) method.

package org.kodejava.jdom;

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

public class JDOMDocumentToString {
    public static void main(String[] args) {
        Document document = new Document();
        Element root = new Element("rows");

        // Creating a child for the root element. Here we can see how to
        // set the text of an xml element.
        Element child = new Element("row");
        child.addContent(new Element("firstname").setText("Alice"));
        child.addContent(new Element("lastname").setText("Mallory"));
        child.addContent(new Element("address").setText("Sunset Road"));

        // Add the child to the root element and add the root element as
        // the document content.
        root.addContent(child);
        document.setContent(root);

        // Create an XMLOutputter object with pretty formatter. Calling
        // the outputString(Document doc) method convert the document
        // into string data.
        XMLOutputter outputter = new XMLOutputter(Format.getPrettyFormat());
        String xmlString = outputter.outputString(document);
        System.out.println(xmlString);
    }
}

The result of our code snippet:

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

Maven Dependencies

<!-- https://search.maven.org/remotecontent?filepath=org/jdom/jdom2/2.0.6.1/jdom2-2.0.6.1.jar -->
<dependency>
    <groupId>org.jdom</groupId>
    <artifactId>jdom2</artifactId>
    <version>2.0.6.1</version>
</dependency>

The following example demonstrates how to read mixed content of an xml element. A mixed content can have more than one type of content such as text (Text), comment (Comment), CDATA (CDATA) or some child elements (Element).

You also see that we can remove the mixed content from the element by calling the remove method of the List just like what we do with a collection of data.

package org.kodejava.jdom;

import org.jdom2.*;
import org.jdom2.input.SAXBuilder;

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

public class JDOMMixedContent {
    public static void main(String[] args) {
        String xml = """
                <root> \
                    <data> \
                        <!-- This element contains application data --> \
                        User Information \
                        <![CDATA[<table><tr><td>-data-</td></tr></table>]]> \
                        <field name="username">alice</field> \
                    </data> \
                </root>""";

        SAXBuilder builder = new SAXBuilder();
        try {
            Document document = builder.build(new StringReader(xml));
            Element root = document.getRootElement();
            Element data = root.getChild("data");

            // Reading the mixed content of an xml element and iterate
            // the result list. This list object can contain any of the
            // following objects: Comment, Element, CDATA, DocType,
            // ProcessingInstruction, EntityRef and Text.
            List<Content> contents = data.getContent();

            for (Content content : contents) {
                if (content instanceof Comment comment) {
                    System.out.println("Comment   = " + comment);
                } else if (content instanceof Element element) {
                    System.out.println("Element   = " + element);
                } else if (content instanceof CDATA cdata) {
                    System.out.println("CDATA     = " + cdata);
                } else if (content instanceof DocType docType) {
                    System.out.println("DocType   = " + docType);
                } else if (content instanceof ProcessingInstruction pi) {
                    System.out.println("PI        = " + pi);
                } else if (content instanceof EntityRef entityRef) {
                    System.out.println("EntityRef = " + entityRef);
                } else if (content instanceof Text text) {
                    System.out.println("Text      = " + text);
                }
            }

            // Remove the second mixed contents which is the CDATA contents.
            contents.remove(2);
        } catch (JDOMException | IOException e) {
            e.printStackTrace();
        }
    }
}

Here are the result of our program:

Text      = [Text:          ]
Comment   = [Comment: <!-- This element contains application data -->]
Text      = [Text:          User Information         ]
CDATA     = [CDATA: <table><tr><td>-data-</td></tr></table>]
Text      = [Text:          ]
Element   = [Element: <field/>]
Text      = [Text:      ]

Maven Dependencies

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

This example demonstrates how to add CDATA section into an xml document. A CDATA section indicates a block that shouldn’t be parsed. To build a CDATA section just wrap the string with a CDATA object.

package org.kodejava.jdom;

import org.jdom2.CDATA;
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.IOException;
import java.io.StringReader;

public class JDOMBuildCDATASection {
    public static void main(String[] args) {
        String xml = """
                <root>
                   <comments>
                       <comment></comment>
                   </comments>
                </root>""";

        SAXBuilder builder = new SAXBuilder();
        try {
            Document document = builder.build(new StringReader(xml));
            Element root = document.getRootElement();
            Element comments = root.getChild("comments");

            Element comment = comments.getChild("comment");

            // Using the setContent and addContent to add CDATA section
            // into  the xml element.
            comment.setContent(
                    new CDATA("<b>This is a bold string</b>."));
            comment.addContent(
                    new CDATA("<i>And this an italic string</i>."));

            XMLOutputter outputter =
                    new XMLOutputter(Format.getPrettyFormat());
            outputter.output(document, System.out);

            // Reading a CDATA section is simply done by calling the 
            // getText method. It doesn't care if it was a simple string
            // or a CDATA section, it will just return the content as 
            // string.
            String text = comment.getText();
            System.out.println("Text = " + text);
        } catch (JDOMException | IOException e) {
            e.printStackTrace();
        }
    }
}

The output of the code snippet above:

<?xml version="1.0" encoding="UTF-8"?>
<root>
  <comments>
    <comment><![CDATA[<b>This is a bold string</b>.]]><![CDATA[<i>And this an italic string</i>.]]></comment>
  </comments>
</root>
Text = <b>This is a bold string</b>.<i>And this an italic string</i>.

Maven Dependencies

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

This example show you how so set text content of XML element. Using JDOM we can easily insert text such as HTML tags without worrying about escaping the tags. JDOM will automatically do this conversion.

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.IOException;
import java.io.StringReader;

public class JDOMSetTextContent {
    public static void main(String[] args) {
        String xml = """
                <root>
                    <description>
                    </description>
                </root>""";

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

            Element root = document.getRootElement();
            Element description = root.getChild("description");

            // Adding a text content to the description element. The string
            // will be escaped automatically, so we don't have to use the 
            // < and > symbol.
            description.setText("This is an <strong>IMPORTANT</strong> " +
                    "description");

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

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.IOException;
import java.io.StringReader;

public class JDOMElementTextContent {
    public static void main(String[] args) {
        String xml = """
                <root>
                    <paragraph>
                Lorem ipsum dolor sit amet, consectetur adipisicing \
                elit, sed do eiusmod tempor incididunt ut labore et \
                dolore magna aliqua. Ut enim ad minim veniam, quis \
                nostrud exercitation ullamco laboris nisi ut aliquip \
                ex ea commodo consequat. Duis aute irure dolor in \
                reprehenderit in voluptate velit esse cillum dolore \
                eu fugiat nulla pariatur. Excepteur sint occaecat \
                cupidatat non proident, sunt in culpa qui officia \
                deserunt mollit anim id est laborum.
                    </paragraph>
                </root>""";

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

            Element root = document.getRootElement();
            Element paragraph = root.getChild("paragraph");

            // Returns the textual content directly held under this element as 
            // a string. This includes all text within this single element, 
            // including whitespace and CDATA sections if they exist.
            String content = paragraph.getText();
            System.out.println("content = " + content);

            // Returns the textual content of this element with all surrounding
            // whitespace removed. If no textual value exists for the element,
            // or if only whitespace exists, the empty string is returned.
            String contentTrimmed = paragraph.getTextTrim();
            System.out.println("contentTrimmed = " + contentTrimmed);

            // Returns the textual content of this element with all surrounding
            // whitespace removed and internal whitespace normalized to a single
            // space. If no textual value exists for the element, or if only
            // whitespace exists, the empty string is returned.
            String contentNormalize = paragraph.getTextNormalize();
            System.out.println("contentNormalize = " + contentNormalize);
        } catch (JDOMException | IOException e) {
            e.printStackTrace();
        }
    }
}

Maven Dependencies

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

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>