Converting JSON to XML in Java

Use the (excellent) JSON-Java library from json.org then

JSONObject json = new JSONObject(str);
String xml = XML.toString(json);

toString can take a second argument to provide the name of the XML root node.

This library is also able to convert XML to JSON using XML.toJSONObject(java.lang.String string)

Check the Javadoc

POM

<dependency>
    <groupId>org.json</groupId>
    <artifactId>json</artifactId>
    <version>20160212</version>
</dependency>

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