Ignore @JsonValue annotation without subclassing

Question

Let's suppose there is a class hierarchy in some third-party library. One of those classes has @JsonValue annotation. It results in serialization/deserialization of only one field. Is it possible to ignore @JsonValue annotation without subclassing and get all object fields serialized?

Answer 1

You can define a MixIn and override the @JsonValue via property or getter - depending on where the annotation has been set in the third-party library.

Assuming we have a class Pojo with a @JsonValue annotated member prop:

class Pojo {
    @JsonValue
    private String prop;
    private String prop2;
    // getters and setters
}

We then define an abstract MixIn class like follows, overriding the particular member or method:

abstract class MixIn {
    @JsonValue(false) // either annotating members
    private String prop;

    @JsonValue(false) // or annotating methods
    abstract String getProp();
}

This can be added to the ObjectMapper like follows:

objectMapper.addMixIn(Pojo.class, MixIn.class);

Instead of just prop, now both prop and prop2 are serialized.