title: JHipster best way to update entity field when another is called
body: <p>I used jHipster to generate stock management project, and i want to update Product quantity field whenever i do a Transaction (selling product [create, update, and delete]).</p>
  
  <p>So, is it better (best practices) to create a web service in my Product resource (backend) called updateProductQuantity and call it in my angular when user do transaction, or do it in the backend and update database using only java code.</p>