Is it possible to create a list of information in JSON format in UI Designer?

I am displaying data that is brought into the database in some Dropdowns, as if it were some sort of shopping cart page from E-Commerce sites, at the moment my page looks like this:
https://drive.google.com/file/d/0B8aMiLwwVY0nX1hBNC01Q1RaS0k/view?usp=sh...

But I need to store this in a list each time the user clicks the Add button, I'm developing in a tool called BonitaSoft, which is geared towards developing systems automation software, I wonder if it's possible to store this item list In JSON, to then be able to display to the user in a table everything that is in that list in a table.

If you have some example of how to save a list in JSON and how to bring the contents of that list into a table would be perfect.