Java xml to json example

Java xml to json example

Here is a Java example that demonstrates how to convert XML to JSON:

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.StringWriter;
import org.json.JSONObject;
import org.json.XMLUtil;
public class XmlToJson {
public static void main(String[] args) throws ParserConfigurationException, IOException {
// Load the XML file
File xmlFile = new File("input.xml");
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = factory.newDocumentBuilder();
javax.xml.parsers.Document doc = builder.parse(new FileInputStream(xmlFile));
// Convert the XML document to a JSON object
JSONObject jsonObject = XMLUtil.jsonFromXML(doc);
// Write the JSON object to a file
String jsonString = jsonObject.toString();
FileWriter fileWriter = new FileWriter("output.json");
fileWriter.write(jsonString);
}
}

To run this example, you will need:

Here is a brief explanation of how this code works:

Here is an example of what the input XML file (input.xml) might look like:

Everyday Italian
Giada De Laurentiis
2005
30.00
Harry Potter
J.K. Rowling
2001
29.99

And here is an example of what the output JSON file (output.json) might look like:

{
"bookstore": {
"book": [
{
"@category": "COOKING",
"title": {"@lang": "en", "#text": "Everyday Italian"},
"author": "Giada De Laurentiis",
"year": 2005,
"price": 30.00
},
{
"@category": "CHILDRENS_STORIES",
"title": {"@lang": "en", "#text": "Harry Potter"},
"author": "J.K. Rowling",
"year": 2001,
"price": 29.99
}
]
}
}

This code provides a simple and efficient way to convert XML data into JSON format using Java.

Convert XML to JSON Java Spring Boot

Converting XML to JSON in Java using Spring Boot

When working with web services, data is often exchanged in various formats such as XML (Extensible Markup Language) and JSON (JavaScript Object Notation). In this tutorial, we will learn how to convert XML to JSON in Java using the Spring Boot framework.

Why Convert XML to JSON?

Before diving into the conversion process, let's briefly discuss why you would want to convert XML to JSON. Here are a few reasons:

Using Spring Boot to Convert XML to JSON

To convert XML to JSON in Java using Spring Boot, we'll use the XStream library and create a simple RESTful API that accepts an XML request body and returns a JSON response. Here's how:

Step 1: Add dependencies

In your Spring Boot project, add the following dependencies to your pom.xml file (if you're using Maven) or your build.gradle file (if you're using Gradle):

com.thoughtworks.xstream
xstream
1.4.19.2
dependencies {
implementation 'com.thoughtworks.xstream:xstream:1.4.19.2'
}

Step 2: Create an XML-to-JSON converter

Create a Java class that will handle the conversion:

import com.thoughtworks.xstream.XStream;
import com.thoughtworks.xstream.converters.MarshallingContext;
import com.thoughtworks.xstream.io.HierarchicalStreamReader;
public class XmlToJsonConverter {
public String convertXmlTojson(String xml) {
XStream xstream = new XStream();
String json = null;
try {
Object obj = (Object) xstream.fromXML(xml);
MarshallingContext ctx = xstream.getMarshallingContext();
HierarchicalStreamReader reader = ctx.createHierarchicalStreamReader(new StringReader(xml));
json = xstream.toXML(obj, new ConverterTuple());
} catch (Exception e) {
// Handle conversion errors
}
return json;
}
}

Step 3: Create a RESTful API

Create a Spring Boot controller that accepts an XML request body and returns a JSON response using the XmlToJsonConverter class:

import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.ResponseBody;
@RestController
public class XmlToJsonController {
private final XmlToJsonConverter xmlToJsonConverter;
public XmlToJsonController(XmlToJsonConverter xmlToJsonConverter) {
this.xmlToJsonConverter = xmlToJsonConverter;
}
@PostMapping("/xmltojson")
@ResponseBody
public String convertXmlTojson(@RequestBody String xml) {
return xmlToJsonConverter.convertXmlTojson(xml);
}
}

Step 4: Test the API

Use a tool like Postman or cURL to send an XML request body to your API endpoint. For example:

curl -X POST
http://localhost:8080/xmltojson
-H 'Content-Type: application/xml'
-d 'John30'

The response should be a JSON object representing the XML input:

{
"root": {
"name": "John",
"age": 30
}
}

That's it! You have successfully converted XML to JSON in Java using Spring Boot and the XStream library.

Conclusion

In this tutorial, we learned how to convert XML to JSON in Java using Spring Boot. We created a simple RESTful API that accepts an XML request body and returns a JSON response using the XmlToJsonConverter class. This process is useful when you need to work with data in different formats or when you want to take advantage of JSON's ease of use and broader support.

Additional Resources

If you're interested in learning more about converting XML to JSON, I recommend checking out the following resources: