Json parsing where a field can have two different types using gson or jackson

Question

I have json with a field that contains two different types.

"fields":[{"value":"ZIELONE OKO"},{"value":{"@nil":"true"}}]

I have a problem with deserialization. My class with model contains:

private String value;

And I just need to translate {"@nil": "true"} to null. Now I get the error message:

The JsonDeserializer StringTypeAdapter failed to deserialized json object {"@nil":"true"} given the type class java.lang.String

Answer 1

Ideally, I would change the code that creates this odd JSON: shouldn't the second value just be JSON null? I assume it is created by a complex process, starting with XML (which should use "isNul" to distinguish between a null string and an empty string).

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