How to accept arbitrary json in rest service?

Question

Java

The service must accept data in json format, and parse this data into classes that extend one abstract class. The service must accept any descendants of the parent abstract class.
Which descendant of the class we should accept will be clear only after checking the context.
How can this be implemented.
Java 7

Answer 1

let the controller in java accept HttpServletRequest or MultipartServletRequest, then parse the necessary data from there in the controller/service