JSON数据的差异对比工具（Java版）

阳光穿透心脏的1/2处 2024-03-31 14:39 39阅读 0赞

**目录**

背景

说明

源码

源码走读

其他

--------------------

### 背景 ###

之前有类似接口diff对比，数据对比的测试需求，涉及到json格式的数据对比，调研了几个大神们分享的代码，选了一个最符合自己需求的研究了下。（可惜原文链接找不到了，原始作者看到了可以私信我下）

### 说明 ###

这个对比方法，支持JsonObject和JsonArray类型的数据对比，支持：

*  深度的对比：list变化（个数、内容）、层级结构变化
 *  字段的对比：新增、修改、删除数据可察觉，能找到对应的旧数据
 *  支持特定字段忽略对比

输出的对比结果格式为：

![8083c52c63174fcffecd08843b496b6b.png][]

源码分为JsonCompareUtils， JsonAndMapSortUtils两个类，对比入口是compareTwoJson方法

核心逻辑在JsonCompareUtils类中，JsonAndMapSortUtils主要做过程中的数据排序功能，相对独立。

### 源码 ###

package com.xhzyqa.transcodetest.utils;
    
    
    import com.alibaba.fastjson.JSON;
    import com.alibaba.fastjson.JSONArray;
    import com.alibaba.fastjson.JSONObject;
    import org.apache.commons.lang.ArrayUtils;
    import org.apache.commons.lang.StringUtils;
    
    import java.util.HashMap;
    import java.util.Iterator;
    import java.util.LinkedHashMap;
    import java.util.Map;
    import java.util.stream.Stream;
    
    public class JsonCompareUtils {
    
        //标志位：对json报文中含有JsonArray类型的数据是否进行排序
        private static boolean isSort;
    
        private Map<String, Object> oldJsonToMap = new LinkedHashMap<>();
        private Map<String, Object> newJsonToMap = new LinkedHashMap<>();
    
        //每一个实体里的排序字段
        private static Map<String, String> filedNameMap = new HashMap<>();
    
        static {
            filedNameMap.put("dogs", "dogNo");
            filedNameMap.put("cats", "catNo");
        }
    
        //可以跳过比对的字段
    //    private static String[] skipCompareFiledNameMap = {"dogAge", "catAge", "catName"};
        private static String[] skipCompareFiledNameMap = {"key3"};
    
        /**
         * 两json报文比对入口
         *
         * @param oldJsonStr
         * @param newJsonStr
         * @return
         */
        public String compareTwoJson(String oldJsonStr, String newJsonStr) {
            /**
             * 递归遍历json对象所有的key-value，以map形式的path:value进行存储
             * 然后对两个map进行比较
             */
            convertJsonToMap(JSON.parseObject(oldJsonStr), "", false);
            convertJsonToMap(JSON.parseObject(newJsonStr), "", true);
            //获取比较结果
            Map<String, Object> differenceMap = compareTwoMaps(oldJsonToMap, newJsonToMap);
            String diffJsonResult = convertMapToJson(differenceMap);
            return diffJsonResult;
        }
    
        /**
         * 将json数据转换为map存储--用于后续比较map
         *
         * @param json
         * @param root
         * @param isNew 区别新旧报文
         */
        private void convertJsonToMap(Object json, String root, boolean isNew) {
            if (json instanceof JSONObject) {
                JSONObject jsonObject = ((JSONObject) json);
                Iterator iterator = jsonObject.keySet().iterator();
                while (iterator.hasNext()) {
                    Object key = iterator.next();
                    Object value = jsonObject.get(key);
                    String newRoot = "".equals(root) ? key + "" : root + "." + key;
                    fillInResultMap(value, newRoot, isNew);
                }
            } else if (json instanceof JSONArray) {
                JSONArray jsonArray = (JSONArray) json;
                //将jsonArray进行排序
                if (isSort) {
                    //需要排序
                    String sortEntityName = root.substring(root.lastIndexOf(".") + 1);
                    String sortFiledName = filedNameMap.get(sortEntityName);//需要排序 获取排序字段
                    if (!StringUtils.isEmpty(sortFiledName)) {
                        jsonArray = JsonAndMapSortUtils.jsonArrayToSort(jsonArray, sortFiledName, true);
                    }
                }
                final JSONArray jsonArray1 = jsonArray;
                Stream.iterate(0, integer -> integer + 1).limit(jsonArray1.size()).forEach(index -> {
                    Object value = jsonArray1.get(index);
                    String newRoot = "".equals(root) ? "[" + index + "]" : root + ".[" + index + "]";
                    fillInResultMap(value, newRoot, isNew);
                });
            }
        }
    
        /**
         * 封装json转map后的数据
         *
         * @param value
         * @param newRoot
         * @param isNew   区别新旧json
         */
        public void fillInResultMap(Object value, String newRoot, boolean isNew) {
            if (value instanceof JSONObject || value instanceof JSONArray) {
                convertJsonToMap(value, newRoot, isNew);
            } else {
                //设置跳过比对的字段，直接不装入map
                boolean check = ArrayUtils.contains(JsonCompareUtils.skipCompareFiledNameMap, newRoot);
                if (!check){
                    if (!isNew) {
                        oldJsonToMap.put(newRoot, value);
                    } else {
                        newJsonToMap.put(newRoot, value);
                    }
                }
            }
        }
    
        /**
         * 比较两个map，将不同的数据以map形式存储并返回
         *
         * @param oldJsonMap
         * @param newJsonMap
         * @return
         */
        private Map<String, Object> compareTwoMaps(Map<String, Object> oldJsonMap, Map<String, Object> newJsonMap) {
            //1.将newJsonMap的不同数据装进oldJsonMap，同时删除oldJsonMap中与newJsonMap相同的数据
            newJsonMap.forEach((k, v) -> {
                Map<String, Object> differenceMap = new HashMap<>();
                String lastFieldKey = k.substring(k.lastIndexOf(".") + 1);
    //            boolean check = ArrayUtils.contains(JsonCompareUtils.skipCompareFiledNameMap, lastFieldKey);
    //            if (!check){
                if (oldJsonMap.containsKey(k)) {
    //                boolean check = ArrayUtils.contains(JsonCompareUtils.skipCompareFiledNameMap, lastFieldKey);
                    Object oldValue = oldJsonMap.get(k);
                    if (v.equals(oldValue)) {
                        oldJsonMap.remove(k);
                    } else {
                        differenceMap.put("oldValue", oldValue);
                        differenceMap.put("newValue", v);
                        oldJsonMap.put(k, differenceMap);
                    }
                } else {
                    differenceMap.put("oldValue", "no exists " + k);
                    differenceMap.put("newValue", v);
                    oldJsonMap.put(k, differenceMap);
                }
    //            }else {
    //                oldJsonMap.remove(k);
    //            }
            });
            //2.统一oldJsonMap中newMap不存在的数据的数据结构，便于解析
            oldJsonMap.forEach((k, v) -> {
                String lastFieldKey = k.substring(k.lastIndexOf(".") + 1);
    //            boolean check = ArrayUtils.contains(JsonCompareUtils.skipCompareFiledNameMap, lastFieldKey);
    //            if (!check && !(v instanceof Map)) {
                if (!(v instanceof Map)) {
                    Map<String, Object> differenceMap = new HashMap<>();
                    differenceMap.put("oldValue", v);
                    differenceMap.put("newValue", "no exists " + k);
                    oldJsonMap.put(k, differenceMap);
                }
            });
            return oldJsonMap;
        }
    
        /**
         * 将已经找出不同数据的map根据key的层级结构封装成json返回
         *
         * @param map
         * @return
         */
        private String convertMapToJson(Map<String, Object> map) {
            JSONObject resultJSONObject = new JSONObject();
            for (Iterator<Map.Entry<String, Object>> it = map.entrySet().iterator(); it.hasNext(); ) {
                Map.Entry<String, Object> item = it.next();
                String key = item.getKey();
                Object value = item.getValue();
                String[] paths = key.split("\\.");
                int i = 0;
                Object remarkObject = null;//用於深度標識對象
                int indexAll = paths.length - 1;
                while (i <= paths.length - 1) {
                    String path = paths[i];
                    if (i == 0) {
                        //初始化对象标识
                        if (resultJSONObject.containsKey(path)) {
                            remarkObject = resultJSONObject.get(path);
                        } else {
                            if (indexAll > i) {
                                if (paths[i + 1].matches("\\[[0-9]+\\]")) {
                                    remarkObject = new JSONArray();
                                } else {
                                    remarkObject = new JSONObject();
                                }
                                resultJSONObject.put(path, remarkObject);
                            } else {
                                resultJSONObject.put(path, value);
                            }
                        }
                        i++;
                        continue;
                    }
                    if (path.matches("\\[[0-9]+\\]")) {//匹配集合对象
                        int startIndex = path.lastIndexOf("[");
                        int endIndext = path.lastIndexOf("]");
                        int index = Integer.parseInt(path.substring(startIndex + 1, endIndext));
                        if (indexAll > i) {
                            if (paths[i + 1].matches("\\[[0-9]+\\]")) {
                                while (((JSONArray) remarkObject).size() <= index) {
                                    if (((JSONArray) remarkObject).size() == index) {
                                        ((JSONArray) remarkObject).add(index, new JSONArray());
                                    } else {
                                        ((JSONArray) remarkObject).add(null);
                                    }
                                }
                            } else {
                                while (((JSONArray) remarkObject).size() <= index) {
                                    if (((JSONArray) remarkObject).size() == index) {
                                        ((JSONArray) remarkObject).add(index, new JSONObject());
                                    } else {
                                        ((JSONArray) remarkObject).add(null);
                                    }
                                }
                            }
                            remarkObject = ((JSONArray) remarkObject).get(index);
                        } else {
                            while (((JSONArray) remarkObject).size() <= index) {
                                if (((JSONArray) remarkObject).size() == index) {
                                    ((JSONArray) remarkObject).add(index, value);
                                } else {
                                    ((JSONArray) remarkObject).add(null);
                                }
                            }
                        }
                    } else {
                        if (indexAll > i) {
                            if (paths[i + 1].matches("\\[[0-9]+\\]")) {
                                if (!((JSONObject) remarkObject).containsKey(path)) {
                                    ((JSONObject) remarkObject).put(path, new JSONArray());
                                }
                            } else {
                                if (!((JSONObject) remarkObject).containsKey(path)) {
                                    ((JSONObject) remarkObject).put(path, new JSONObject());
                                }
                            }
                            remarkObject = ((JSONObject) remarkObject).get(path);
                        } else {
                            ((JSONObject) remarkObject).put(path, value);
                        }
                    }
                    i++;
                }
            }
            return JSON.toJSONString(resultJSONObject);
        }
    
        public boolean isSort() {
            return isSort;
        }
    
        public void setSort(boolean sort) {
            isSort = sort;
        }
    
        public static void main(String[] args) {
            String oldStr = "{key1:'aaa',key2:'bbb'}";
            String newStr = "{key1:'aaa',key2:'bbb',key3:'c'}";
            System.out.println(new JsonCompareUtils().compareTwoJson(oldStr, newStr));
            System.out.println("\n========测试复杂json的比对============");
        }
    
        /**
         * 测试类
    
        static class JsonCompareTest {
            public static void compareTest() {
                String oldJson = MakeJsonCompareDatas.getJsonDataOldStr();
                String newJson = MakeJsonCompareDatas.getJsonDataNewStr();
    
                //对json报文中含有JsonArray类型的数据是否进行排序
                JsonCompareUtils.isSort = true;
    
                String compareResult = new JsonCompareUtils().compareTwoJson(oldJson, newJson);
                System.out.println("oldJson==>" + oldJson);
                System.out.println("newJson==>" + newJson);
                System.out.println("\nisSort==" + isSort + "-->compareResult==>\n" + compareResult);
    
    
    
            }
        }
         */
    }

package com.xhzyqa.transcodetest.utils;
    
    
    import com.alibaba.fastjson.JSONArray;
    import com.alibaba.fastjson.JSONObject;
    import sun.misc.ASCIICaseInsensitiveComparator;
    
    import java.util.*;
    import java.util.function.Function;
    import java.util.stream.Collectors;
    
    public class JsonAndMapSortUtils {
    
        /**
         * map排序
         * @param map
         * @param keySort
         * @param <k>
         * @param <v>
         * @return
         */
        public static <k,v> List mapByKeyToSort(Map<k,v> map , final Comparator keySort){
            List<Map.Entry<k,v>> entryList = new ArrayList<Map.Entry<k, v>>(map.entrySet());
            Collections.sort(entryList, new Comparator<Map.Entry<k, v>>() {
                public int compare(Map.Entry<k, v> o1, Map.Entry<k, v> o2) {
                    return keySort.compare(o1.getKey(),o2.getKey());
                }
            });
            //return (Map<k,v>)entryList.stream().collect(Collectors.toMap(Map.Entry<k,v>::getKey, Function.identity(), (key1, key2) -> key2));
            Map<String,String> afterToSortMap = new HashMap<>();
            /*for (Map.Entry<k,v> m : entryList){
                System.out.println(m.getKey()+"===>"+m.getValue());
            }*/
            System.out.println("排序=====");
            entryList.forEach(m->{
                System.out.println(m.getKey()+"===>"+m.getValue());
            });
            return entryList;
        }
    
        /**
         * JSONArray排序
         * @param jsonArray
         * @param fildName
         * @param isAsc
         * @return
         */
        public static JSONArray jsonArrayToSort(JSONArray jsonArray,final String fildName,final boolean isAsc){
            JSONArray afterSortJsonArray = new JSONArray();
            List<JSONObject> objectList = new ArrayList<JSONObject>();
            jsonArray.forEach(obj ->{
                objectList.add((JSONObject)obj);
            });
            Collections.sort(objectList, new Comparator<JSONObject>() {
                @Override
                public int compare(JSONObject o1, JSONObject o2) {
                    String fildValueA = o1.getString(fildName);
                    String fildValueB = o2.getString(fildName);
                    if (isAsc)
                        return fildValueA.compareTo(fildValueB);
                    return fildValueB.compareTo(fildValueA);
                }
            });
            objectList.forEach(obj->{
                afterSortJsonArray.add(obj);
            });
            return afterSortJsonArray;
        }
    
        /**
         *准备map测试数据
         */
        public static Map<String,String> getMapData(){
            LinkedHashMap<String,String> map = new LinkedHashMap<>();
            map.put("key1","麦兜");
            map.put("key3","贝塔");
            map.put("key5","酥妮");
            map.put("key2","小H");
            map.put("key4","小O");
            return map;
        }
        /**
         *准备json测试数据
         */
        public static JSONArray getJsonArrayData(){
            JSONArray jsonArray = new JSONArray();
            JSONObject jsonObject1 = new JSONObject();
            jsonObject1.put("userId","1001");
            jsonObject1.put("name","麦兜");
            jsonArray.add(jsonObject1);
    
            JSONObject jsonObject3 = new JSONObject();
            jsonObject3.put("userId","1003");
            jsonObject3.put("name","酥妮");
            jsonArray.add(jsonObject3);
    
            JSONObject jsonObject2 = new JSONObject();
            jsonObject2.put("userId","1002");
            jsonObject2.put("name","贝塔");
            jsonArray.add(jsonObject2);
    
            return jsonArray;
        }
    
        public static void main(String[] args) {
            Map<String,String> map = JsonAndMapSortUtils.getMapData();
            JSONArray jsonArray = JsonAndMapSortUtils.getJsonArrayData();
            List afterSortMap = JsonAndMapSortUtils.mapByKeyToSort(map,new ASCIICaseInsensitiveComparator());
    
            JSONArray afterSortJsonArray_isAsc = JsonAndMapSortUtils.jsonArrayToSort(jsonArray,"userId",true);
            JSONArray afterSortJsonArray_noAsc = JsonAndMapSortUtils.jsonArrayToSort(jsonArray,"userId",false);
    
            System.out.println("map排序前："+map);
            System.out.println("map排序后："+afterSortMap+"\n");
    
            System.out.println("JsonArray排序前："+jsonArray);
            System.out.println("JsonArray排序后==》升序："+afterSortJsonArray_isAsc);
            System.out.println("JsonArray排序后==》降序："+afterSortJsonArray_noAsc);
        }
    
    
    }

### 源码走读 ###

整个源码调用链路如下图，简单来说过程就是：object拆分解析-新旧数据逐个对比-结果信息组装三个步骤

![0af43dc85a312b78739d5f109319fa3b.png][]

### 其他 ###

原始代码中有些小bug，已修复。目前这个工具主要被我拿来用在了一个接口数据对比工具中，来检测迭代前后的接口协议数据变更，以完善迭代变更范围来确认测试范围

[8083c52c63174fcffecd08843b496b6b.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/03/31/ff0bb3ad0a5b4710aa478c48b42b31d1.png
[0af43dc85a312b78739d5f109319fa3b.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/03/31/74c277c6594d40548d83eff4a5c4b97f.png