Is it possible to setup Jersey using Jackson for serialization/deserialization using multiple configured ObjectMappers
?
What I would like to be able to do is register a "default" Jackson ObjectMapper
and then have the ability to register another feature which provides an ObjectMapper
with some specialized configuration which under certain circumstance will "override" the "default" ObjectMapper
.
For example, this ContextResolver
would be for the "default" mapper:
@Provider
@Consumes(MediaType.APPLICATION_JSON)
@Produces(MediaType.APPLICATION_JSON)
public class JacksonMapperProvider implements ContextResolver<ObjectMapper> {
private final ObjectMapper mObjectMapper;
public JacksonMapperProvider() {
mObjectMapper = createMapper();
}
protected abstract ObjectMapper createMapper() {
ObjectMapper mapper = createMapper();
return mapper
.setSerializationInclusion(Include.ALWAYS)
.configure(JsonParser.Feature.ALLOW_COMMENTS, true)
.configure(JsonParser.Feature.ALLOW_UNQUOTED_FIELD_NAMES, true)
.configure(JsonParser.Feature.ALLOW_SINGLE_QUOTES, true)
.configure(JsonParser.Feature.ALLOW_UNQUOTED_CONTROL_CHARS, true);
}
@Override
public ObjectMapper getContext(Class<?> type) {
return mObjectMapper;
}
}
And this ContextResolver
would be to override the "default" mapper:
@Provider
@Consumes(MediaType.APPLICATION_JSON)
@Produces(MediaType.APPLICATION_JSON)
public class SpecializedMapperProvider implements ContextResolver<ObjectMapper> {
private final ObjectMapper mObjectMapper;
public SpecializedMapperProvider() {
mObjectMapper = createMapper();
}
protected abstract ObjectMapper createMapper() {
ObjectMapper mapper = createMapper();
return mapper
.disable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS)
.setDateFormat(new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS"))
.registerModule(new SpecializedModule1())
.registerModule(new SpecializedModule2());
}
@Override
public ObjectMapper getContext(Class<?> type) {
if(SomeType.isAssignableFrom(type)) {
return mObjectMapper;
}
return null;
}
}
I see in the JacksonJsonProvider
code that Jackson supports ObjectMapper
provider injection/resolution. However, in practice, what I am seeing is that the "order" of the providers seems random (I'm guessing it's not, but I can't sort out how to control the order). Sometimes the "override" comes before the "default" and everything works, but on the next server startup the order changes.
I have attempted to get this to work in a number of ways including:
- Registering the
ContextResolver<ObjectMapper>
implementations manually (in differing orders) - Registering the
ContextResolver<ObjectMapper>
implementations via@Provider
annotations - Specifying a priority when registering
I am using the following:
- Jersey 2.8
- Jackson 2.3.3
Perhaps I am taking a completely incorrect approach?
Is there a better way to achieve what I am trying to do?
Maybe I should just define two separate JAX-RS applications and have a single ObjectMapper configuration for each?