JSON-to-XML Conversion Library for Java

XML Tutorials - Herong's Tutorial Examples

∟JSON-to-XML Conversion Library for Java

This section provides a tutorial example on how to use a 'JSON-java' conversion library offered by json.org to perform JSON-to-XML conversions in Java program. The output JSON document is good, only if input XML document contains well structured data.

If you are familiar with Java language, you can try to use the "JSON-java" library to convert your JSON document to an XML document.

1. Go to "JSON-java" Website at https://github.com/stleary/JSON-java.

2. Click "Click here if you just want the latest release jar file" link and save the jar file, json-20200518.jar, to the current directory.

3. Create a Java program, Xml2Json.java, to use the "JSON-java" library to convert a JSON document to an XML document:

/* Xml2Json.java
 * Copyright (c) 2018 HerongYang.com. All Rights Reserved.
 */
import java.io.*;
import java.nio.file.*;
import org.json.XML;
import org.json.JSONObject;
public class Xml2Json {
  public static void main(String[] args) throws IOException {
    String input = args[0];
    String json = new String(Files.readAllBytes(Paths.get(input)));
    JSONObject jsonObj = new JSONObject(json);
    String xml = XML.toString(jsonObj);
    System.out.println(xml);
  }
}

4. Run Xml2Json.java to convert our JSON sample document, sample.json:

herong> java -cp json-20200518.jar Json2Xml.java sample.json 

<dictionary>
  <word>
    <origin>null</origin>
    <name>
      <is acronym>true</is acronym>
      <value>DTD</value>
    </name>
    <update>
      <date>2020-01-01</date>
    </update>
    <definition>Document Type Definition</definition>
  </word>
  <word>
    <origin>docga</origin>
    <name>
      <is acronym>false</is acronym>
      <value>Dog</value>
    </name>
    <update>
      <date>1000-01-01</date>
    </update>
    <definition>A domesticated carnivorous mammal</definition>
  </word>
</dictionary>

As you can see, this conversion tool uses almost the same conversion rules as I suggested, except that special characters in the JSON property names are not replaced. For example, "is acronym" is used as an XML element name directly, which results an invalid XML document.