Question: how to create jdl file?
Answer: simply creating a file with the extension '. jh' or '. ... 
declare your entities and relationships or create and download the file with JDL-Studio,
in your JHipster application's root folder, simply run jhipster:import-jdl yourfile. jh ,
you can also use JDL files in JHipster UML with jhipster-uml my_file. jdl .