custom ValidationError class in jersey to send only string message of error

Question

The ValidationError class of jersey2.x looks something like this

@XmlRootElement
public final class ValidationError {
 private String message;
    private String messageTemplate;
    private String path;
    private String invalidValue;
 
    ...
}

which when error occurs returns string like this

Contact with given ID does not exist. (path = ContactCardResource.getContact.<return value>, invalidValue = null)

But what i need is consistent error message response interface for client . Which should send back only string messages . So this should not include class name and method name .For Some validation which dosen't depend on bean validation ,For example duplicate username . I just send string with 400 or 500 status code . I want to do same with Bean Validation how can this be achieved

Answer 1

Bean-Validation throws ConstraintViolationException and you can write a custom exception mapper to handle ConstraintViolationException as shown below.

@Singleton
@Provider
public class ConstraintViolationMapper implements ExceptionMapper<ConstraintViolationException> {

@Override
public Response toResponse(ConstraintViolationException e) {
    // There can be multiple constraint Violations
    Set<ConstraintViolation<?>> violations = e.getConstraintViolations();
    List<String> messages = new ArrayList<>();
    for (ConstraintViolation<?> violation : violations) {
        messages.add(violation.getMessage());

    }
    return Response.status(Status.BAD_REQUEST).entity(StringUtils.join(messages,";")).build();
}

}

Register above mapper in your ResourceConfig or Appication .