Using this SDK to generate CWL Documents

Can this SDK be used to generate CWL documents?
We are trying to add a CWL exporter to our project (we have our workflows stored in a custom format) and since we have a Java backend, I was hopping that we could use the classes generated in this SDK to create the documents and then export them in YAML. However I don't see any setters in the generated classes, or constructors that I could use to export our definitions into CWL `CommandLineTool`, `Workflow`, etc. Am I missing something?
I also tried to use schema-salad to re-generate the Java classes but couldn't find the option to generate the classes differently.