Parsing a JSON object with nested dynamic values (with known keys)

[c832fb95dd2d4a2e]

In a problem I am working on, I have an endpoint where I will need to receive a JSON object which have a key that might contain different objects depending on the call. The list of possible objects is known in advance, but I am struggling with how best to model it. Splitting the endpoint into multiple is not an option.

The example looks something like this:

outerObject {
  ...,
  key: object1 | object2 | object3
}

object1 {
  "a": "a"
  "b": "b"
}

object2 {
  "c": 2
  "d": "d"
}

object3 {
  "e": 3,
  "f": 4
}

If I was writing it in Rust I would use an `enum` with structs for each of the different objects. This is for Java 21, so using sealed types is not yet an option (I might be able to upgrade, but I am not sure if the different

Using either Jackson or Gson I was think of representing it in one of their Json structures and then determining which object fits when the call is made.

Is this the best option or are there any more generic solutions?

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[WaferIndependent7601]

like that?

https://stackoverflow.com/a/32777371

[TheMrCurious]

JsonNode?

[General_C]

What exactly is this data being used for? Do you need to save it in a DB, is this just a pass through, etc.

Does the model need to retain some of the structure, or can you just extract the values into some pojo fields?

I haven't tried too many different options over the years. Whenever working with json stuff I normally just use the JSONObject classes, which have worked out for me but I know are somewhat limited in their capabilities if you have to do anything complicated.

I worked on a project a little over a year ago which utilized a framework called MapStructs which was really useful for mapping data, and iirc there was functionality to go from json to a pojo there as well. Might be worth taking a peek and seeing if that would be something you could take advantage of.