JSON 快速克隆的另一种形式

• 起始节点 - 数组“[]”

 

 

•  起始节点 - 对象“{}”

 

 

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONArray;
import com.alibaba.fastjson.JSONObject;
import com.alibaba.fastjson.serializer.SerializerFeature;
 
/**
* @author 测试
* 
*/
public class Test {
 
    public static String jsonObjStr = "{\"k.1\":\"123\",\"k.2\":{\"k.2.1\":10,\"k.2.2\":[1,2,3.4],\"key\":11}}";
 
    public static String jsonArrStr = "[\"k.3.4\",{\"k.1\":\"123\",\"k.2\":{\"k.2.1\":10,\"k.2.2\":[1,2,3.4],\"key\":11}}]";
 
    private Object parse(String jsonStr) {
        JSONObject jsonObj = new JSONObject();
        JSONObject newJsonObj = new JSONObject();
        Object obj = JSON.parse(jsonStr);
        if (obj instanceof JSONArray) {
            jsonObj.put("jsonList", obj);
        } else if (obj instanceof JSONObject) {
            jsonObj = (JSONObject) obj;
        }
        dfs(jsonObj, newJsonObj);
        if (newJsonObj.containsKey("jsonList")) {
            return newJsonObj.get("jsonList");
        }
        return newJsonObj;
    }
 
    private void dfs(Object obj, Object newObj) {
        if (obj == null) {
            return;
        }
 
        if (obj instanceof JSONObject) {
            JSONObject jsonObject = (JSONObject) obj;
            JSONObject newJsonObject = (JSONObject) newObj;
            jsonObject.forEach((key, value) -> {
                // 避免“.”号本来就在 Key 当中, 具有业务含义
                String newKey = key.replace(".", "#");
                Object newValue = getNewValue(value);
                if (newValue == null) {
                    newJsonObject.put(newKey, value);
                } else {
                    newJsonObject.put(newKey, newValue);
                    dfs(value, newJsonObject.get(newKey));
                }
            });
        } else if (obj instanceof JSONArray) {
            JSONArray jsonArray = (JSONArray) obj;
            JSONArray newJsonArray = (JSONArray) newObj;
            for (int i = 0; i < jsonArray.size(); i++) {
                Object newValue = getNewValue(jsonArray.get(i));
                if (newValue == null) {
                    newJsonArray.add(jsonArray.get(i));
                } else {
                    newJsonArray.add(newValue);
                    dfs(jsonArray.get(i), newJsonArray.get(i));
                }
            }
        }
    }
 
    private Object getNewValue(Object obj) {
        if (obj instanceof JSONObject) {
            return new JSONObject();
        } else if (obj instanceof JSONArray) {
            return new JSONArray();
        }
        return null;
    }
 
    public static void main(String[] args) {
//        Object result = new Test().parse(jsonObjStr);
        Object result = new Test().parse(jsonArrStr);
        System.out.println(JSON.toJSONString(result, SerializerFeature.WriteMapNullValue));
    }
}

• 输出

• // 对象节点
  {"k#1":"123","k#2":{"k#2#1":10,"k#2#2":[1,2,3.4],"key":11}}
   
  // 数组节点
  ["k.3.4",{"k#1":"123","k#2":{"k#2#1":10,"k#2#2":[1,2,3.4],"key":11}}]

   

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