统计年，月，日，java补充无的数据

需求：营收趋势图。需要按年，按月，按日。按年，后方选择日历 起始年-结束年。例如start2013 end 2023
按月，后方选择月份 起始月-结束月。例如start 2022-10 end 2023-07。
按日，后方选择日 起始日-结束日。例如 start 2023-06-15 end 2023-07-11。

先来用sql统计。sql分组统计出有的年月日。没有的数据用java补充即可。

展示对象

查询对象

改造成动态sql。根据type。分组不一样。

<select id="chart" resultType="com.xxxx.TaxiOrderChartVO"
          parameterType="com.xxxx.TaxiOrderChartQuery">
	select
    count(distinct user_id) as useNum,
    count(id) as orderNum,
    <if test="type=='YEAR'">
      YEAR(create_time) as type
    </if>
    <if test="type=='MONTH'">
      DATE_FORMAT(create_time,'%Y-%m') as type
    </if>
    <if test="type=='DAY'">
      DATE_FORMAT(create_time,'%Y-%m-%d') as type
    </if>
    from cz_taxi_orders
    <where>
      <if test="type=='YEAR'">
        <if test="start != null and start != '' && end != null and end != ''">
           YEAR(create_time) BETWEEN #{start} and #{end}
        </if>
      </if>
      <if test="type=='MONTH'">
        <if test="start != null and start != '' && end != null and end != ''">
          DATE_FORMAT(create_time,'%Y-%m') BETWEEN #{start} and #{end}
        </if>
      </if>
      <if test="type=='DAY'">
        <if test="start != null and start != '' && end != null and end != ''">
          DATE_FORMAT(create_time,'%Y-%m-%d') BETWEEN #{start} and #{end}
        </if>
      </if>
    </where>
    group by type
  </select>

Java代码

@Override
    public R chart(TaxiOrderChartQuery query) throws ParseException {
        List<TaxiOrderChartVO> list = taxiOrderMapper.chart(query);
        //年 yyyy
        List<TaxiOrderChartVO> list1 = new ArrayList<>();
        //月 yyyy-MM
        List<TaxiOrderChartVO> list2 = new ArrayList<>();
        //日 yyyy-MM-dd
        List<TaxiOrderChartVO> list3 = new ArrayList<>();
        //按年统计,没有的年份补充0
        if (query.getType().equals("YEAR")){
            Integer end = Integer.valueOf(query.getEnd());
            Integer start = Integer.valueOf(query.getStart());
            for (int i = start; i <= end; i++) {
                TaxiOrderChartVO vo = new TaxiOrderChartVO();
                boolean flag = false;
                for (TaxiOrderChartVO chartVO : list) {
                    if (chartVO.getType().equals(String.valueOf(i))){
                        flag = true;
                        vo.setOrderNum(chartVO.getOrderNum());
                        vo.setUseNum(chartVO.getUseNum());
                        vo.setType(chartVO.getType());
                    }
                }
                if (!flag){
                    vo.setUseNum(0);
                    vo.setType(String.valueOf(i));
                    vo.setOrderNum(0);
                }
                list1.add(vo);
            }
            return R.ok(list1);
        }
        //按月统计,2023-01至2023-12,没有的部分补充0
        if (query.getType().equals("MONTH")){
            List<String> monthBetweenDate = DateUtils.getMonthBetweenDate(query.getStart(), query.getEnd());
            for (String month : monthBetweenDate) {
                TaxiOrderChartVO vo  = new TaxiOrderChartVO();
                boolean flag = false;
                for (TaxiOrderChartVO chartVO : list) {
                    if (chartVO.getType().equals(month)){
                        flag = true;
                        vo.setOrderNum(chartVO.getOrderNum());
                        vo.setUseNum(chartVO.getUseNum());
                        vo.setType(chartVO.getType());
                    }

                }
                if (!flag){
                    vo.setUseNum(0);
                    vo.setType(month);
                    vo.setOrderNum(0);
                }
                list2.add(vo);
            }

            return R.ok(list2);
        }
        //按日统计,2023-01-12至2023-02-10,没有的部分补充0
        if (query.getType().equals("DAY")){
            List<String> dayBetweenDate = DateUtils.getDayBetweenDate(query.getStart(), query.getEnd());
            for (String day : dayBetweenDate) {
                TaxiOrderChartVO vo  = new TaxiOrderChartVO();
                boolean flag = false;
                for (TaxiOrderChartVO chartVO : list) {
                    if (chartVO.getType().equals(day)){
                        flag = true;
                        vo.setOrderNum(chartVO.getOrderNum());
                        vo.setUseNum(chartVO.getUseNum());
                        vo.setType(chartVO.getType());
                    }

                }
                if (!flag){
                    vo.setUseNum(0);
                    vo.setType(day);
                    vo.setOrderNum(0);
                }
                list3.add(vo);
            }

            return R.ok(list3);
        }
        return R.ok(list);
    }

月，日工具类

package com.zyx.common.utils;

import java.text.SimpleDateFormat;
import java.util.*;

/**
 * @author zyx
 * @date 2023/4/13 15:20
 */

public class DateUtils {

    /**
     * 获取两个日期之间的所有月份 (年月)
     * @param startTime
     * @param endTime
     * @return：list
     */
    public static List<String> getMonthBetweenDate(String startTime, String endTime) {
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM");
        // 声明保存日期集合
        List<String> list = new ArrayList<>();
        try {
            // 转化成日期类型
            Date startDate = sdf.parse(startTime);
            Date endDate = sdf.parse(endTime);
            //用Calendar 进行日期比较判断
            Calendar calendar = Calendar.getInstance();
            while (startDate.getTime() <= endDate.getTime()) {
                // 把日期添加到集合
                list.add(sdf.format(startDate));
                // 设置日期
                calendar.setTime(startDate);
                //把月数增加 1
                calendar.add(Calendar.MONTH, 1);
                // 获取增加后的日期
                startDate = calendar.getTime();
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        return list;
    }

    /**
     * 获取两个日期之间的所有天数 (年月日)
     * @param startTime
     * @param endTime
     * @return：list
     */
    public static List<String> getDayBetweenDate(String startTime, String endTime) {
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
        // 声明保存日期集合
        List<String> list = new ArrayList<>();
        try {
            // 转化成日期类型
            Date startDate = sdf.parse(startTime);
            Date endDate = sdf.parse(endTime);
            //用Calendar 进行日期比较判断
            Calendar calendar = Calendar.getInstance();
            while (startDate.getTime() <= endDate.getTime()) {
                // 把日期添加到集合
                list.add(sdf.format(startDate));
                // 设置日期
                calendar.setTime(startDate);
                //把天数增加 1
                calendar.add(Calendar.DATE, 1);
                // 获取增加后的日期
                startDate = calendar.getTime();
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        return list;
    }
    
}

访问接口文档。测试效果。可以实现，接下来就是和前端沟通按年传YEAR，按月传MONTH，按日传DAY即可。