JAVA对JSON字符串进行时间排序

[{
	"BEGDA": "0000-00-00",
	"ENDDA": "0000-00-00",
	"PERNR": "00000000",
	"USRID": "",
	"USRTY": ""
}, {
	"BEGDA": "2019-04-15",
	"ENDDA": "9999-12-31",
	"PERNR": "",
	"USRID": "17666294051",
	"USRTY": "MPHN"
}, {
	"BEGDA": "2020-01-01",
	"ENDDA": "9999-12-31",
	"PERNR": "10004398",
	"USRID": "12345678",
	"USRTY": "MAIL"
}, {
	"BEGDA": "2019-04-15",
	"ENDDA": "9999-12-31",
	"PERNR": "",
	"USRID": "17666294051",
	"USRTY": "MPHN"
}, {
	"BEGDA": "2020-01-01",
	"ENDDA": "9999-12-31",
	"PERNR": "",
	"USRID": "12345678",
	"USRTY": "MAIL"
}]

先看一下这端JSON格式，怎么弄得呢？字符串JSON，我怎么toString直接就可以生成JSON字符串呢？

	 


    //这个加到你JAVA类里面，this指针，指向自身类，然后你调用这个类接受数据库查询或者调用webservice回调得结果，都可以直接toString拿到JSON字符串
        @Override
		public String toString() {
			return JSONObject.fromObject(this).toString();
		}

 

 

需求是我们将以BEGDA排序，怎么排呢？

package com.sap.util;

import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONArray;
import com.alibaba.fastjson.JSONException;
import com.alibaba.fastjson.JSONObject;

public class JsonArraySortOrderByDate {
	 /**
     * 按照JSONArray中的对象的某个字段进行排序(采用fastJson)
     * @param jsonArrStr json数组字符串
     * 
     * @param jsonArrStr keyName变量
     * 
     */
    public  String JsonOrderByDate(String jsonArrStr) {
        JSONArray jsonArr = JSON.parseArray(jsonArrStr);
        JSONArray sortedJsonArray = new JSONArray();
        List<JSONObject> jsonValues = new ArrayList<JSONObject>();
        for (int i = 0; i < jsonArr.size(); i++) {
            jsonValues.add(jsonArr.getJSONObject(i));
        }
        Collections.sort(jsonValues, new Comparator<JSONObject>() {
          private final String KEY_NAME = "ZXJRQ";
            String string1;
            String string2;
            @Override
            public int compare(JSONObject a, JSONObject b) {
        try {
                     string1= a.getString(KEY_NAME).replaceAll("-", "");
                     string2= b.getString(KEY_NAME).replaceAll("-", "");
                } catch (JSONException e) {
                    // 处理异常
                }
                    //这里是按照时间逆序排列,不加负号为正序排列
                return -string1.compareTo(string2);
            }
        });
        for (int i = 0; i < jsonArr.size(); i++) {
            sortedJsonArray.add(jsonValues.get(i));
        }
        return sortedJsonArray.toString();
    }
}

这一段，已经很明白了，假设你要联合排得话，将改造一下 

 

未结束~~~