Arrays 如何在java ArrayNode的元素中插入键值？

这些是我要修改的json文件

{
    "realtime_start": "2020-11-08",
    "realtime_end": "2020-11-08",
    "observation_start": "2007-01-01",
    "observation_end": "2018-01-01",
    "observations": [
        {
            "realtime_start": "2020-11-08",
            "realtime_end": "2020-11-08",
            "date": "2007-01-01",
            "value": "23.23"
        },
        {
            "realtime_start": "2020-11-08",
            "realtime_end": "2020-11-08",
            "date": "2007-02-01",
            "value": "23.87"
        },
        {
            "realtime_start": "2020-11-08",
            "realtime_end": "2020-11-08",
            "date": "2007-03-01",
            "value": "23.13"
        }
}

我尝试在ArrayNode的每个元素中插入键和值

{
        "realtime_start": "2020-11-08",
        "realtime_end": "2020-11-08",
        "observation_start": "2007-01-01",
        "observation_end": "2018-01-01",
        "observations": [
            {
                "id": "testId",
                "realtime_start": "2020-11-08",
                "realtime_end": "2020-11-08",
                "date": "2007-01-01",
                "value": "23.23"
            },
            {
                "id": "testId",
                "realtime_start": "2020-11-08",
                "realtime_end": "2020-11-08",
                "date": "2007-02-01",
                "value": "23.87"
            },
            {
                "id": "testId",
                "realtime_start": "2020-11-08",
                "realtime_end": "2020-11-08",
                "date": "2007-03-01",
                "value": "23.13"
            }
    }

我使用JsonNode.get api提取ArrayNode，如下所示，并尝试插入值

JsonNode nodeValue = mapper.readTree(new URL(tmpUrl));  // returns the above json file
ArrayNode nodeValueObserv = (ArrayNode)nodeValue.get("observations");
nodeValueObserv.insert(0, "testId"));

但是结果没有正确生成

{
        "realtime_start": "2020-11-08",
        "realtime_end": "2020-11-08",
        "observation_start": "2007-01-01",
        "observation_end": "2018-01-01",
        "observations": [
           "testId",
           {
                "realtime_start": "2020-11-08",
                "realtime_end": "2020-11-08",
                "date": "2007-01-01",
                "value": "23.23"
            },
            {
                "realtime_start": "2020-11-08",
                "realtime_end": "2020-11-08",
                "date": "2007-02-01",
                "value": "23.87"
            },
            {
                "realtime_start": "2020-11-08",
                "realtime_end": "2020-11-08",
                "date": "2007-03-01",
                "value": "23.13"
            }
    }

请告知我如何使用java com.fasterxml.jackson.databind.node.ArrayNode API将键值放入ArrayNode的每个元素中。致以最良好的祝愿