JMeter jp@gc Parametrized controller - construct object from variables

Question

How to construct an object with attributes taken only from jp@gc-Parametrized controller user defined variables list, that can be used for building dynamically xml/json data structures for HTTP Sampler later on?

Controller variables:

XML structure for HTTP request body:

Example 1:

 <?xml version="1.0" encoding="UTF-8"?>
    <login>
        <username>someUser</username>
        <password>1234</password>
    </login>

Answer 1

It's saving JMeter variables, so you can use ${} syntax

<userName>${username}</userName>
<password>${password}</password>

To get dynamically variables in XML Body use the following sample

import java.util.stream.StreamSupport;
String xmlBody="<?xml version=\"1.0\" encoding=\"UTF-8\"?><login>";
StreamSupport.stream(Spliterators.spliteratorUnknownSize(vars.getIterator(), Spliterator.ORDERED), false).forEach(
    e -> xmlBody+="<" +e.getKey() + ">" +e.getValue() + "</" +e.getKey() + ">");
xmlBody += "</login>";
log.info(xmlBody);

Answer 2

Assuming your above Parameterized Controller setup you can refer the declared variables like:

<?xml version="1.0" encoding="UTF-8"?>
<login>
    <username>${username}</username>
    <password>${password}</password>
</login>

Which will result into variables substitution in the runtime with their respective values which can be checked using i..e View Results Tree listener :

Check out JMeter Parameterization - The Complete Guide article for more information on various approaches to JMeter test parameterization.