Start Parsing within Nested JSON Object with Jackson

Question

I have the following JSON structure:

{
  "uri": {
    "{{firstname}}": "Peter",
    "{{lastname}}": "Griffin",
    "{{age}}": 42
  }
}

I want to deserialize it into my Bean:

public class Uri {

    private String firstname;
    private String lastname;
    private int age;

    /* getter and setter */
}

But I get the following error:

com.fasterxml.jackson.databind.exc.UnrecognizedPropertyException: Unrecognized field "uri" (class com.abc.Uri), not marked as ignorable (3 known properties: "firstname", "lastname", "age")

So I assume, I need to get into the property uri .

Is there any way, to start parsing directly within the uri property?

Update:

This is how I read the JSON:

ObjectMapper mapper = new ObjectMapper();
uri = mapper.readValue(new URL("test2.json"), Uri.class);

Answer 1

You JSON should be of the format:

{
  "uri": {
    "firstname": "Peter",
    "lastname": "Griffin",
    "age": 42,
  }
}

Answer 2

Your method will not work because you are trying to get the whole json object at once, without getting a specific node at first.

Instead of loading your json with the mapper constructor, get your json in a different way. I would use URL and HTTPURLConnection to get the json string from the web.

After you have your json string, use this:

 ObjectMapper objectMapper = new ObjectMapper();
 JsonNode rootNode = objectMapper.readTree(json);

Get the json node that uri represents, like this:

JsonNode uriNode = rootNode.get("uri");

And only then send that node to be parsed, like this:

Jackson 2.4

Uri uri = objectMapper.treeToValue(uriNode, Uri.class);

Prior to Jackson 2.4

Uri uri = objectMapper.readValue(uriNode, Uri.class);