i have a restcontroller with following Code
@RequestMapping(method = RequestMethod.POST, value = "/student") public void addTopic(@RequestBody Student student) { student.setPassword(bCryptPasswordEncoder.encode(student.getPassword())); studentService.addStudent(student); } but if the json data doesn't match the Student object, or is wrong formatted an com.fasterxml.jackson.core.JsonParseException: Unexpected character ('"' (code 34)) ist thrown.
what is the best practice to prevent that
I've found that I need to catch JsonProcessingException (which JsonParseException extends from) in the @ExceptionHandler rather than JsonParseException
@ControllerAdvice public class FeatureToggleControllerAdvice { @ExceptionHandler(JsonProcessingException.class) public ResponseEntity<JSONAPIDocument> handleJsonParseException(JsonProcessingException ex) { final Error error = new Error(); error.setId(UUID.randomUUID().toString()); error.setStatus(HttpStatus.BAD_REQUEST.toString()); error.setTitle(ex.getMessage()); return new ResponseEntity<>(JSONAPIDocument .createErrorDocument(Collections.singleton(error)), HttpStatus.NOT_FOUND); } } Using JsonParseException in the above sample and nothing is caught, but using JsonProcessingException works as expected.
Use Spring ExceptionHandler to do that
You could specify an ExceptionHandler based on Exception types and also apply the error codes you want to use.
@ExceptionHandler(JsonParseException.class) public JacksonExceptionHandler { public ResponseEntity<String> handleError(final Exception exception) { HttpStatus status = HttpStatus.BAD_REQUEST; if (exception != null) { LOGGER.warn("Responding with status code {} and exception message {}", status, exception.getMessage()); return new ResponseEntity<>(exception.getMessage(), status); } } Furthermore you could make use of javax.validation to validate the entity you receive and then Spring Boot will do all the validation automagically. Just add @Valid to the body.
