如何对json串按key排序

1. 原JSON串

{
    "key-a": "val-a",
    "key-b": "val-b",
    "key-c": "val-c",
    "key-e": [
    {
        "key-e-4": "val-e-4",
        "key-e-3": "val-e-3"
    },
    {
        "key-e-2": "val-e-2",
        "key-e-1": "val-e-1"
    }],
    "key-d":
    {
        "key-d-3": "val-d-3",
        "key-d-4": "val-d-4",
        "key-d-1": "val-d-1",
        "key-d-2": "val-d-2"
    }
}

2. pom引入

<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>fastjson</artifactId>
    <version>1.2.70</version>
</dependency>

3. 执行操作

final JSONObject jsonObject = JSON.parseObject(jsonString);
final String keySortedJson = JSONObject.toJSONString(jsonObject, SerializerFeature.MapSortField);

4. 输出结果

{
    "key-a": "val-a",
    "key-b": "val-b",
    "key-c": "val-c",
    "key-d":
    {
        "key-d-1": "val-d-1",
        "key-d-2": "val-d-2",
        "key-d-3": "val-d-3",
        "key-d-4": "val-d-4"
    },
    "key-e": [
    {
        "key-e-3": "val-e-3",
        "key-e-4": "val-e-4"
    },
    {
        "key-e-1": "val-e-1",
        "key-e-2": "val-e-2"
    }]
}