How to update a nested entity in MongoDB using Java API

Following code snippet shows how to manipulate given JSON string with Jackson library to add new JSON node and update existing node with specific criteria.
You have to modify the logic to add/udpate nodes according to given request JSON string.

Code snippet

ObjectMapper mapper = new ObjectMapper();
ObjectNode root = (ObjectNode) mapper.readTree(jsonStr);

//create new node to be added
ObjectNode newNode = mapper.createObjectNode();
newNode.put("id", 125);
newNode.put("name", "name2");

ArrayNode arrayNode = (ArrayNode) root.get("MyBson");
arrayNode.forEach(e -> {
    e.get("someEntityParams").forEach(e1 -> {
        //add new node of case1
        if (e1.has("case1")) {
            ((ArrayNode) e1.get("case1")).add(newNode);
        }

        //update existing node of case2 whose id is 136
        if (e1.has("case2")) {
            e1.get("case2").forEach(e2 -> {
                if (e2.get("id").asInt() == 136) {
                    ((ObjectNode) e2).put("onemoreField", "onemoreFieldNew");
                }
            });
        }
    });
});
System.out.println(root.toString());

Console output

{"MyBson":[{"id":"someId","name":"name123","someEntity":["A","B"],"someEntityParams":[{"case1":[{"id":133,"name":"name"},{"id":124,"name":"name1"},{"id":125,"name":"name2"}]},{"case2":[{"id":135,"name":"name2","onemoreField":"field"},{"id":136,"name":"name3","onemoreField":"onemoreFieldNew"},{"id":137,"name":"name4","onemoreField":"field"}]}]}]}