Extract fields from complicated server response

I have a server response that has this format:

{"bankAccounts":[
                  {"id"     :"wfasfsd",
                   "balance":{"amount":90, "currency":"GBP"}
                  }
                ]

I cant find out how to parse through it efficiently
For a similar response with of simpler format this post helped me (https://stackoverflow.com/questions/63702281/extract-jsonobject-and-iterate-through-hashmap-field)

The picture shows exactly how the server response looks like. I need to extract this into JSON and in the end, I need to have a HashMap with keys id, amount, currency

You can use json-simple library to read and write json objects.

Here you can see how to use it.