Java Jackson XML to Map

1. Overview

Handling XML data is a common task in enterprise applications. Often, developers need to convert XML structures to Java Maps for easier manipulation. Jackson's XML module provides a smooth way to achieve this. This guide demonstrates how to convert XML data representing user information into a Java Map.

Check out all the Java Jackson JSON tutorials and examples: 50+ Java Jackson JSON Tutorials with Examples

2. Development Steps

1. Set up a new Maven project.

2. Add the Jackson XML dependencies.

3. Create a User Java class using Jackson XML annotations.

4. Write a method to convert the XML data into a Java Map.

5. Validate the conversion by displaying the Map content.

3. Create a Maven Project

There are different ways to create a simple Maven project:

Create a Simple Maven Project using the Command Line Interface

Create a Simple Maven Project using  Eclipse IDE

Create a Simple Maven Project using  IntelliJ IDEA

4. Maven Dependencies

Open the pom.xml file, and add the following Jackson data binding dependency:

<dependency>
    <groupId>com.fasterxml.jackson.dataformat</groupId>
    <artifactId>jackson-dataformat-xml</artifactId>
    <version>2.13.0</version>
</dependency>

5. Code Program

import com.fasterxml.jackson.dataformat.xml.XmlMapper;
import java.util.Map;
class User {
    private String id;
    private String name;
    
    // Standard getters, setters, and constructor omitted for brevity
}
public class MainApp {
    public static void main(String[] args) {
        String xmlData = "<User><id>1</id><name>John Doe</name></User>";
        
        XmlMapper xmlMapper = new XmlMapper();
        try {
            Map<String, Object> resultMap = xmlMapper.readValue(xmlData, Map.class);
            System.out.println(resultMap);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

Output:

{User={id=1, name=John Doe}}

Code Explanation:

1. The User class provides a simple representation of a user, containing fields for ID and name.

2. The XmlMapper class is utilized to convert XML data into its corresponding Java representation.

3. We provided a sample XML string for demonstration. The readValue method of XmlMapper is then used to convert this XML string into a Java Map.

4. The resulting Map contains key-value pairs corresponding to the XML structure, with outer tags represented as keys pointing to inner Maps.

6. Conclusion

Jackson's XML module offers an efficient way to transform XML data into a Java Map. This capability proves invaluable when processing complex XML structures or when needing a dynamic representation that doesn't tie the developer down to a strict object model.

Check out all the Java Jackson JSON tutorials and examples: 50+ Java Jackson JSON Tutorials with Examples