Hibernate Validator and Jackson: Using the @JsonProperty value as the ConstraintViolation PropertyPath?
Unfortunately there is no easy way to do it. But here are some insights that can help you:
Parsing constraint violations
From the ConstraintViolationException
, you can get a set of ConstraintViolation
, that exposes the constraint violation context:
ConstraintViolation#getLeafBean()
: If it is a bean constraint, this method returns the bean instance in which the constraint is applied to.ConstraintViolation#getPropertyPath()
: Returns the path to the invalid property.
From the property path, you can get the leaf node:
Path propertyPath = constraintViolation.getPropertyPath();
Optional<Path.Node> leafNodeOptional =
StreamSupport.stream(propertyPath.spliterator(), false).reduce((a, b) -> b);
Then check if the type of the node is PROPERTY
and get its name:
String nodeName = null;
if (leafNodeOptional.isPresent()) {
Path.Node leafNode = leafNodeOptional.get();
if (ElementKind.PROPERTY == leafNode.getKind()) {
nodeName = leafNode.getName();
}
}
Introspecting a class with Jackson
To get the available JSON properties from the leaf bean class, you can introspect it with Jackson (see this answer and this answer for further details):
Class<?> beanClass = constraintViolation.getLeafBean().getClass();
JavaType javaType = mapper.getTypeFactory().constructType(beanClass);
BeanDescription introspection = mapper.getSerializationConfig().introspect(javaType);
List<BeanPropertyDefinition> properties = introspection.findProperties();
Then filter the properties by comparing the leaf node name with the Field
name from the BeanPropertyDefinition
:
Optional<String> jsonProperty = properties.stream()
.filter(property -> nodeName.equals(property.getField().getName()))
.map(BeanPropertyDefinition::getName)
.findFirst();
Using JAX-RS?
With JAX-RS (if you are using it), you can define an ExceptionMapper
to handle ConstraintViolationException
s:
@Provider
public class ConstraintViolationExceptionMapper
implements ExceptionMapper<ConstraintViolationException> {
@Override
public Response toResponse(ConstraintViolationException exception) {
...
}
}
To use the ObjectMapper
in your ExceptionMapper
, you could provide a ContextResolver<T>
for it:
@Provider
public class ObjectMapperContextResolver implements ContextResolver<ObjectMapper> {
private final ObjectMapper mapper;
public ObjectMapperContextResolver() {
mapper = createObjectMapper();
}
@Override
public ObjectMapper getContext(Class<?> type) {
return mapper;
}
private ObjectMapper createObjectMapper() {
ObjectMapper mapper = new ObjectMapper();
mapper.configure(SerializationFeature.INDENT_OUTPUT, true);
mapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);
mapper.disable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS);
return mapper;
}
}
Inject the Providers
interface in your ExceptionMapper
:
@Context
private Providers providers;
Lookup for your ContextResolver<T>
and then get the ObjectMapper
instance:
ContextResolver<ObjectMapper> resolver =
providers.getContextResolver(ObjectMapper.class, MediaType.WILDCARD_TYPE);
ObjectMapper mapper = resolver.getContext(ObjectMapper.class);
If you are interested in getting @XxxParam
names, refer to this answer.
No, that's not possible. Hibernate Validator 5 (Bean Validation 1.1) has the notion of ParameterNameProvider
s which return the names to reported in case method parameter constraints are violated but there is nothing comparable for property constraints.