Update JSON values with lambda

Question

I would like to take a JsonNode tree and update each of the values. Can this be done with a lambda expression?

{
    "resource": {
        "key1": "value1",
        "key2": "value2",
        "key3": "value3"
    }
}

I am trying to use the following logic:

JsonNode json = new ObjectMapper().readTree(new ObjectMapper().writeValueAsString(myObject));

ObjectNode rootNode = (ObjectNode) json;
ObjectNode resourceNode = (ObjectNode) rootNode.path("resource");

//Psuedo Code here
resourceNode.forEach(node -> node.value = myFunc(node.value));

Thanks in advance!

I don't think you can, see http://stackoverflow.com/questions/30997362/how-to-modify-jsonnode-in-java — , Jul 29 '16 at 15:42

4castle · Accepted Answer · 2016-07-29T16:13:55.123

4

Use .fields() to iterate over the key/value pairs:

resourceNode.fields().forEachRemaining(
    entry -> resourceNode.set(
        entry.getKey(),
        func(entry.getValue())
    )
);

edited Jul 29 '16 at 16:13

answered Jul 29 '16 at 15:48

4castle

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Yep, that's much better – Andremoniy Jul 29 '16 at 15:50

score 1 · Answer 2 · answered Jul 29 '16 at 15:44

1

Actually you can do that:

resourceNode.fieldNames().forEachRemaining(
      s -> resourceNode.set(s, new TextNode(func(resourceNode.get(s).asText())))
);

answered Jul 29 '16 at 15:44

Andremoniy

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Update JSON values with lambda

2 Answers2