Json-B (not JSONB!), short for Json Binding, is a modern MicroProfile Java standard to convert json documents (json messages) to a java class and vice versa.
This standard is supported by most modern java application containers. But because of a definition gap in the Jax-RS standard, it is not as easy as initially thought to get proper and helpful error messages if an invalid JSON document is encountered in the
POST request body of an endpoint. The
ExceptionMapper will only work after applying a few tricks.