Access JAX-RS resource annotations from a JsonbSerializer - jax-rs

Question

I have an application running on Payara 4 using a custom GSON JSON adapter. I would like to migrate to Payara 5 (5.191) and start using JSON-B. In our current application we can control the JSON output using annotations on a resource.
For example using #Summarize:
#GET
#Path("summary/{encryptedId}")
#Produces(MediaType.APPLICATION_JSON)
#Summarize
public Address findSummarized(#PathParam("encryptedId") String encryptedId) {
return super.find(encryptedId);
}
it will cause a different GSON configuration to be used in our #Provider:
#Provider
#Consumes(MediaType.APPLICATION_JSON)
#Produces(MediaType.APPLICATION_JSON)
public class GsonProvider<T> implements MessageBodyReader<T>, MessageBodyWriter<T> {
public GsonProvider() {
gson = getGson(EntityAdapter.class);
gsonSummary = getGson(EntitySummaryAdapter.class);
}
...
#Override
public void writeTo(T object,
Class<?> type,
Type genericType,
Annotation[] annotations,
MediaType mediaType,
MultivaluedMap<String, Object> httpHeaders,
OutputStream entityStream)
throws IOException, WebApplicationException {
boolean summarize = contains(annotations, Summarize.class);
try (PrintWriter printWriter = new PrintWriter(entityStream)) {
printWriter.write((summarize ? gsonSummary : gson).toJson(object));
printWriter.flush();
}
}
}
I want to do something similar in the new JSON-B setup. I annotated our entities with #JsonbTypeSerializer(MySerializer.class), so I would like to be able to detect from within the serializer what it should do: either create a full serialized JSON object, or a summary.
What I hoped to do is set a property in the JsonbConfig, like so:
JsonbConfig config = new JsonbConfig()
.setProperty("com.myCompany.jsonb.summarize", true);
and read it in the serializer using #Context (just guessing that this might work here), like so:
#Context
private JsonbConfiguration config;
.. but that's not. Is there any way to access JAX-RS resource annotations from a JsonbSerializer?

Answer 1

You could accomplish a similar goal using two separate Jsonb instances in your JAX-RS provider class like so:
#Provider
#Consumes(MediaType.APPLICATION_JSON)
#Produces(MediaType.APPLICATION_JSON)
public class JsonbProvider<T> implements MessageBodyReader<T>, MessageBodyWriter<T> {
private static final Jsonb jsonb = JsonbBuilder.create(new JsonbConfig()
.withAdapters(new EntityAdapter()));
private static final Jsonb jsonbSummary = JsonbBuilder.create(new JsonbConfig()
.withAdapters(new EntitySummaryAdapter()));
...
#Override
public void writeTo(T object,
Class<?> type,
Type genericType,
Annotation[] annotations,
MediaType mediaType,
MultivaluedMap<String, Object> httpHeaders,
OutputStream entityStream)
throws IOException, WebApplicationException {
boolean summarize = contains(annotations, Summarize.class);
try (PrintWriter printWriter = new PrintWriter(entityStream)) {
printWriter.write((summarize ? jsonbSummary : jsonb).toJson(object));
printWriter.flush();
}
}
}

Answer 2

In the end I opted to create summaries from within my entities and drop the annotation on my REST resources. It was a bit of work, but I think it has been worth it.
I created a Summarizable interface and added a default method there to create a simple map summary of any entity, based on a extended version of the PropertyVisibilityStrategy we created for the full version of the entities.
public interface Summarizable {
public default Map<String, Object> toSummary() {
SummaryPropertyVisibilityStrategy summaryStrategy = new SummaryPropertyVisibilityStrategy();
Map<String, Object> summary = new LinkedHashMap<>();
ReflectionUtils.getFields(this.getClass())
.stream()
.filter(summaryStrategy::isVisible)
.map(f -> new AbstractMap.SimpleEntry<>(f.getName(), summarize(f)))
.filter(e -> e.getValue() != null)
.forEach(e -> summary.put(e.getKey(), e.getValue()));
return summary;
}
public default Object summarize(final Field field) {
Object value = ReflectionUtils.getValueJsonb(this, field);
return value != null && Stream.of(ManyToOne.class, OneToOne.class).anyMatch(field::isAnnotationPresent)
? value.toString()
: value;
}
}
public static Object getValueJsonb(final Object object, final Field field) {
field.setAccessible(true);
JsonbTypeAdapter adapterAnnotation = field.getAnnotation(JsonbTypeAdapter.class);
try {
Object value = field.get(object);
return adapterAnnotation == null
? value
: adapterAnnotation.value().newInstance().adaptToJson(value);
}
catch (Exception ex) {
throw new IllegalStateException(ex);
}
}