RESTful Java Web Services - Third Edition

Mapping exceptions to a response message using ExceptionMapper

You can use the javax.ws.rs.ext.ExceptionMapper class to map the checked or unchecked exceptions to the appropriate HTTP response content. At runtime, when an exception is thrown by a method, the JAX-RS runtime will scan through all registered exception mappers to find the best match for handling the exception. If there is no exact match found, runtime considers a mapper class that matches with the parent class of the checked exception class. After identifying the exception mapper class for handling an exception, the framework invokes the toResponse() method on the exception mapper instance to generate the appropriate HTTP response content for the exception.

Here is an example ...