Modify JsonNode of unknown JSON dynamically in Java - jackson

Question

I am trying to modify a JSON (of an unknown structure) where the JsonPath and its equivalent XML Xpath is known to me.
I have tired using com.jayway.jsonpath.JsonPath library for the same.
The problem with JsonPath is, it returns me the value but I am not able to modify the Target Node.
Follows is my code snippet for the same
JsonPath.read(jsonFile, jsonPath);
JsonPath.parse(jsonPath);
System.out.println("Author: "+JsonPath.read(jsonFile, jsonPath));
I tried using Jackson as mentioned in previously asked quetion, But it needs to be traversed node by node as follows
((ObjectNode) parent).put(fieldName, newValue);
which I cannot do due to unknown structure.
I have tried the answer given to the question recursively parse JSON object but it says how to parse not modify
I need to do the follows
JsonNode root = mapper.readTree("Json in form of String");
((JsonNode)(root.get("JsonPath")).set("New Value");
Is there any way in which this can be achieved?

Answer 1

JsonNode objects are immutable so you can't modify them. What you can do is replace a JsonNode with another one. A cast to ObjectNode is also required to expose the required methods. First find the parent of the node you want to replace :
JsonNode node = root.findParent("JsonPath");
Then use either of these 2 methods to replace it with a new one:
((ObjectNode) node).remove("JsonPath"); // remove current node
((ObjectNode) node).put("JsonPath", "New Value"); // add new one with new value
or
((ObjectNode) node).replace("JsonPath", new TextNode("New Value"));