JSOG usage of @JsonTypeInfo and @JsonIdentityInfo(generator=JSOGGenerator.class) implies failure for deserialization

[ericali78]

First happy new year to everybody !
Deserialization seems to work with JSOGGenerator. However when adding @JsonTypeInfo (need this in a model object that have superclass), it does not succeed to.

Sample to reproduce in JSOGTest.java :

@JsonIdentityInfo(generator=JSOGGenerator.class)
@JsonTypeInfo(use=JsonTypeInfo.Id.CLASS, include=JsonTypeInfo.As.PROPERTY, property="@Class")
public static class Inner {
public String bar;
}
In a more global way, the @Class attribute does not seem to be handle or lead to a conflict with @ref management.
Does somebody succed to handle that ? thank you .
Sorry if double post in JSOG jackson plugin is too much (dunno wich is the best place to put/solve)

[cowtowncoder]

May be related to the problem of injecting multiple metadata properties. But how does this fail?
I assume serialization works as expected?

[ericali78]

Hello,
Thanks for your aswer.
Yes the serialization is ok.
-> Serialized to: {"@id":"1","foo":"foo","inner1":{"@Class":"com.voodoodyne.jackson.jsog.JSOGTest$Inner","@id":"2","bar":"bar"},"inner2":{"@ref":"2"}}

But when attempting to deserialize it fails because jacksson thinks that "inner1":{"@Class":"com.voodoodyne.jackson.jsog.JSOGTest$Inner","@id":"2","bar":"bar"} represents an objectid or reference

stack trace :
Caused by: java.lang.NullPointerException
at com.voodoodyne.jackson.jsog.JSOGRefDeserializer.deserialize(JSOGRefDeserializer.java:38)
at com.voodoodyne.jackson.jsog.JSOGRefDeserializer.deserialize(JSOGRefDeserializer.java:18)
at com.fasterxml.jackson.databind.deser.impl.ObjectIdReader.readObjectReference(ObjectIdReader.java:136)
at com.fasterxml.jackson.databind.deser.BeanDeserializerBase.deserializeFromObjectId(BeanDeserializerBase.java:1045)
)

[stickfigure]

I created a PR that adds a failing test case:

#672

I'm not quite sure what is going on. I have a test case for this in the jsog-jackson code and it looks like jackson is trying to deserialize a ref, even the first time it sees the object (when it is a full object with id). But the failure in the PR above looks a little different. I suspect it has the same root cause.

[cowtowncoder]

So the problem is due to interaction between type and object ids. Will need to see what to do with that.

[cowtowncoder]

Turned out to be relatively easy to fix. Phew! For a while thought might be trickier.

One thing that is clear, however, is that for more complex Object Ids (more than a single key/value pair), code would become a pretzel. But that's neither here nor now, so we're good for time being. :)

[ericali78]

Great job
Thank you !