Java JSONArray 去重

末蓝、 2024-03-22 15:45 52阅读 0赞

在处理元素的时候，数据是JSONArray类型，由JSONObject组成，发现有相同一样的元素，要进行去重

数据：

[
    	{
    		"xtype": "5",
    		"formElementAttrs": {
    			"DEFAULT_VALUE": {
    				"value": "FLOW_ID"
    			},
    			"ELEMENT_NAME": {
    				"value": "FLOW_ID"
    			},
    			"DEFAULT_VALUE_TYPE": {
    				"value": "7"
    			},
    			"ELEMENT_NAME_CN": {
    				"value": "流程ID"
    			},
    			"IS_EMPTY": {
    				"value": "F"
    			},
    			"tableName": "SYNC_122"
    		},
    		"tableFieldId": ""
    	},
    	{
    		"xtype": "5",
    		"formElementAttrs": {
    			"DEFAULT_VALUE": {
    				"value": "com.common.generator.IdGeneratorFactory.getId(\"requestId\")"
    			},
    			"ELEMENT_NAME": {
    				"value": "REQUEST_ID"
    			},
    			"DEFAULT_VALUE_TYPE": {
    				"value": "9"
    			},
    			"ELEMENT_NAME_CN": {
    				"value": "请求标识"
    			},
    			"IS_EMPTY": {
    				"value": "F"
    			},
    			"tableName": "SYNC_122"
    		},
    		"tableFieldId": ""
    	},
    	{
    		"xtype": "5",
    		"formElementAttrs": {
    			"DEFAULT_VALUE": {
    				"value": "FLOW_ID"
    			},
    			"ELEMENT_NAME": {
    				"value": "FLOW_ID"
    			},
    			"DEFAULT_VALUE_TYPE": {
    				"value": "7"
    			},
    			"ELEMENT_NAME_CN": {
    				"value": "流程ID"
    			},
    			"IS_EMPTY": {
    				"value": "F"
    			},
    			"tableName": "SYNC_122"
    		},
    		"tableFieldId": ""
    	},
    	{
    		"xtype": "5",
    		"formElementAttrs": {
    			"DEFAULT_VALUE": {
    				"value": "com.common.generator.IdGeneratorFactory.getId(\"requestId\")"
    			},
    			"ELEMENT_NAME": {
    				"value": "REQUEST_ID"
    			},
    			"DEFAULT_VALUE_TYPE": {
    				"value": "9"
    			},
    			"ELEMENT_NAME_CN": {
    				"value": "请求标识"
    			},
    			"IS_EMPTY": {
    				"value": "F"
    			},
    			"tableName": "SYNC_122"
    		},
    		"tableFieldId": ""
    	}
    ]

**目标：**去除重复的内容

### 1，直接用java8 distinct ###

#### 代码： ####

public static JSONArray distincTheSame(JSONArray elements) {
            JSONArray distinctArr = new JSONArray();
            List<JSONObject> distinctList = ListUtils.emptyIfNull(elements).stream().map((e) -> (JSONObject) e).distinct().collect(Collectors.toList());
            distinctArr.addAll(distinctList);
            return distinctArr;
        }

#### 测试： ####

public static void main(String args[]) {
            JSONArray distinctArr = distincTheSame(initDataTheSame());
            System.out.println("=========== the same ===========");
            System.out.println(distinctArr.toJSONString());
    
            distinctArr = distincTheSame(initDataDiffernt());
            System.out.println("=========== the same different ===========");
            System.out.println(distinctArr.toJSONString());
    
            distinctArr = distincDiffernet(initDataDiffernt());
            System.out.println("=========== different ===========");
            System.out.println(distinctArr.toJSONString());
        }
    
         public static JSONArray initDataTheSame() {
            String data = "[{\"xtype\":\"5\",\"formElementAttrs\":{\"DEFAULT_VALUE\":{\"value\":\"FLOW_ID\"},\"ELEMENT_NAME\":{\"value\":\"FLOW_ID\"},\"DEFAULT_VALUE_TYPE\":{\"value\":\"7\"},\"ELEMENT_NAME_CN\":{\"value\":\"流程ID\"},\"IS_EMPTY\":{\"value\":\"F\"},\"tableName\":\"SYNC_122\"},\"tableFieldId\":\"\"},{\"xtype\":\"5\",\"formElementAttrs\":{\"DEFAULT_VALUE\":{\"value\":\"com.common.generator.IdGeneratorFactory.getId(\\\"requestId\\\")\"},\"ELEMENT_NAME\":{\"value\":\"REQUEST_ID\"},\"DEFAULT_VALUE_TYPE\":{\"value\":\"9\"},\"ELEMENT_NAME_CN\":{\"value\":\"请求标识\"},\"IS_EMPTY\":{\"value\":\"F\"},\"tableName\":\"SYNC_122\"},\"tableFieldId\":\"\"},{\"xtype\":\"5\",\"formElementAttrs\":{\"DEFAULT_VALUE\":{\"value\":\"FLOW_ID\"},\"ELEMENT_NAME\":{\"value\":\"FLOW_ID\"},\"DEFAULT_VALUE_TYPE\":{\"value\":\"7\"},\"ELEMENT_NAME_CN\":{\"value\":\"流程ID\"},\"IS_EMPTY\":{\"value\":\"F\"},\"tableName\":\"SYNC_122\"},\"tableFieldId\":\"\"},{\"xtype\":\"5\",\"formElementAttrs\":{\"DEFAULT_VALUE\":{\"value\":\"com.common.generator.IdGeneratorFactory.getId(\\\"requestId\\\")\"},\"ELEMENT_NAME\":{\"value\":\"REQUEST_ID\"},\"DEFAULT_VALUE_TYPE\":{\"value\":\"9\"},\"ELEMENT_NAME_CN\":{\"value\":\"请求标识\"},\"IS_EMPTY\":{\"value\":\"F\"},\"tableName\":\"SYNC_122\"},\"tableFieldId\":\"\"}]";
            return JSONArray.parseArray(data);
        }

#### 结果： ####

=========== the same ===========
    [{"xtype":"5","formElementAttrs":{"DEFAULT_VALUE":{"value":"FLOW_ID"},"ELEMENT_NAME":{"value":"FLOW_ID"},"DEFAULT_VALUE_TYPE":{"value":"7"},"ELEMENT_NAME_CN":{"value":"流程ID"},"IS_EMPTY":{"value":"F"},"tableName":"SYNC_122"},"tableFieldId":""},{"xtype":"5","formElementAttrs":{"DEFAULT_VALUE":{"value":"com.common.generator.IdGeneratorFactory.getId(\"requestId\")"},"ELEMENT_NAME":{"value":"REQUEST_ID"},"DEFAULT_VALUE_TYPE":{"value":"9"},"ELEMENT_NAME_CN":{"value":"请求标识"},"IS_EMPTY":{"value":"F"},"tableName":"SYNC_122"},"tableFieldId":""}]

#### 不同 ####

如果内容不是完全一样的，比如数据变成了

[
    	{
    		"xtype": "5",
    		"formElementAttrs": {
    			"DEFAULT_VALUE": {
    				"value": "FLOW_ID"
    			},
    			"ELEMENT_NAME": {
    				"value": "FLOW_ID"
    			},
    			"DEFAULT_VALUE_TYPE": {
    				"value": "7"
    			},
    			"ELEMENT_NAME_CN": {
    				"value": "流程ID"
    			},
    			"IS_EMPTY": {
    				"value": "F"
    			},
    			"tableName": "SYNC_122"
    		},
    		"tableFieldId": 363021235
    	},
    	{
    		"xtype": "5",
    		"formElementAttrs": {
    			"DEFAULT_VALUE": {
    				"value": "com.common.generator.IdGeneratorFactory.getId(\"requestId\")"
    			},
    			"ELEMENT_NAME": {
    				"value": "REQUEST_ID"
    			},
    			"DEFAULT_VALUE_TYPE": {
    				"value": "9"
    			},
    			"ELEMENT_NAME_CN": {
    				"value": "请求标识"
    			},
    			"IS_EMPTY": {
    				"value": "F"
    			},
    			"tableName": "SYNC_122"
    		},
    		"tableFieldId": 363021236
    	},
    	{
    		"xtype": "5",
    		"formElementAttrs": {
    			"DEFAULT_VALUE": {
    				"value": "FLOW_ID"
    			},
    			"ELEMENT_NAME": {
    				"value": "FLOW_ID"
    			},
    			"DEFAULT_VALUE_TYPE": {
    				"value": "7"
    			},
    			"ELEMENT_NAME_CN": {
    				"value": "流程ID"
    			},
    			"IS_EMPTY": {
    				"value": "F"
    			},
    			"tableName": "SYNC_122"
    		},
    		"tableFieldId": 363021237
    	},
    	{
    		"xtype": "5",
    		"formElementAttrs": {
    			"DEFAULT_VALUE": {
    				"value": "com.common.generator.IdGeneratorFactory.getId(\"requestId\")"
    			},
    			"ELEMENT_NAME": {
    				"value": "REQUEST_ID"
    			},
    			"DEFAULT_VALUE_TYPE": {
    				"value": "9"
    			},
    			"ELEMENT_NAME_CN": {
    				"value": "请求标识"
    			},
    			"IS_EMPTY": {
    				"value": "F"
    			},
    			"tableName": "SYNC_122"
    		},
    		"tableFieldId": 363021238
    	}
    ]

再调用相同方法就不行了。 这时候就要根据指定值进行过滤。 保留前面的，去掉后面重复的内容。

### 2，根据指定值进行过滤 ###

#### 代码： ####

public static JSONArray distincDiffernet(JSONArray elements) {
            List<String> fieldNames = new ArrayList<>();
            JSONArray distinctArr = new JSONArray();
            ListUtils.emptyIfNull(elements).stream().map((e) -> (JSONObject)e).forEach(e -> {
                String fileName = e.getJSONObject("formElementAttrs").getJSONObject("ELEMENT_NAME").getString("value");
                if(!fieldNames.contains(fileName)){
                    fieldNames.add(fileName);
                    distinctArr.add(e);
                }
            });
            return distinctArr;
        }

#### 测试： ####

public static void main(String args[]) {  
            distinctArr = distincDiffernet(initDataDiffernt());
            System.out.println("=========== different ===========");
            System.out.println(distinctArr.toJSONString());
        }
    
    
        public static JSONArray initDataDiffernt(){
            String data = "[{\"xtype\":\"5\",\"formElementAttrs\":{\"DEFAULT_VALUE\":{\"value\":\"FLOW_ID\"},\"ELEMENT_NAME\":{\"value\":\"FLOW_ID\"},\"DEFAULT_VALUE_TYPE\":{\"value\":\"7\"},\"ELEMENT_NAME_CN\":{\"value\":\"流程ID\"},\"IS_EMPTY\":{\"value\":\"F\"},\"tableName\":\"SYNC_122\"},\"tableFieldId\":363021235},{\"xtype\":\"5\",\"formElementAttrs\":{\"DEFAULT_VALUE\":{\"value\":\"com.common.generator.IdGeneratorFactory.getId(\\\"requestId\\\")\"},\"ELEMENT_NAME\":{\"value\":\"REQUEST_ID\"},\"DEFAULT_VALUE_TYPE\":{\"value\":\"9\"},\"ELEMENT_NAME_CN\":{\"value\":\"请求标识\"},\"IS_EMPTY\":{\"value\":\"F\"},\"tableName\":\"SYNC_122\"},\"tableFieldId\":363021236},{\"xtype\":\"5\",\"formElementAttrs\":{\"DEFAULT_VALUE\":{\"value\":\"FLOW_ID\"},\"ELEMENT_NAME\":{\"value\":\"FLOW_ID\"},\"DEFAULT_VALUE_TYPE\":{\"value\":\"7\"},\"ELEMENT_NAME_CN\":{\"value\":\"流程ID\"},\"IS_EMPTY\":{\"value\":\"F\"},\"tableName\":\"SYNC_122\"},\"tableFieldId\":363021237},{\"xtype\":\"5\",\"formElementAttrs\":{\"DEFAULT_VALUE\":{\"value\":\"com.common.generator.IdGeneratorFactory.getId(\\\"requestId\\\")\"},\"ELEMENT_NAME\":{\"value\":\"REQUEST_ID\"},\"DEFAULT_VALUE_TYPE\":{\"value\":\"9\"},\"ELEMENT_NAME_CN\":{\"value\":\"请求标识\"},\"IS_EMPTY\":{\"value\":\"F\"},\"tableName\":\"SYNC_122\"},\"tableFieldId\":363021238}]";
            return JSONArray.parseArray(data);
        }

#### 结果： ####

=========== different ===========
    [{"xtype":"5","formElementAttrs":{"DEFAULT_VALUE":{"value":"FLOW_ID"},"ELEMENT_NAME":{"value":"FLOW_ID"},"DEFAULT_VALUE_TYPE":{"value":"7"},"ELEMENT_NAME_CN":{"value":"流程ID"},"IS_EMPTY":{"value":"F"},"tableName":"SYNC_122"},"tableFieldId":363021235},{"xtype":"5","formElementAttrs":{"DEFAULT_VALUE":{"value":"com.common.generator.IdGeneratorFactory.getId(\"requestId\")"},"ELEMENT_NAME":{"value":"REQUEST_ID"},"DEFAULT_VALUE_TYPE":{"value":"9"},"ELEMENT_NAME_CN":{"value":"请求标识"},"IS_EMPTY":{"value":"F"},"tableName":"SYNC_122"},"tableFieldId":363021236}]

### 总结： ###

对于JSONArray的过滤，如果子元素相同，可以用java8直接用distinct进行去重。如果内容有差别的，根据需求，用指定内容的值进行去重