java获取两个日期之间的所有日期，获取两个月份之间的所有月份

package com.sitech.bds.dg.dq.util;

import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.Collections;
import java.util.Comparator;
import java.util.Date;
import java.util.List;

public class DateUtil {
  /**
   * 获取两个日期之间的所有日期
   * @param startTime 开始日期
   * @param endTime 结束日期
   * @return
   */
  public static List<String> getDayBetween(String startTime, String endTime) {

      // 返回的日期集合
      List<String> days = new ArrayList<String>();

      DateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");
      try {
          Date start = dateFormat.parse(startTime);
          Date end = dateFormat.parse(endTime);

          Calendar tempStart = Calendar.getInstance();
          tempStart.setTime(start);

          Calendar tempEnd = Calendar.getInstance();
          tempEnd.setTime(end);
          tempEnd.add(Calendar.DATE, +1);// 日期加1(包含结束)
          while (tempStart.before(tempEnd)) {
              days.add(dateFormat.format(tempStart.getTime()));
              tempStart.add(Calendar.DAY_OF_YEAR, 1);
          }

      } catch (ParseException e) {
          e.printStackTrace();
      }

      return days;
  }
  
  /**
     *   获取两个月份之间的所有月份(含跨年)
     * @param minDate
     * @param maxDate
     * @return
     * @throws ParseException
     */
    public static List<String> getMonthBetween(String minDate, String maxDate) {
    ArrayList<String> result = new ArrayList<String>();
    SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM");// 格式化为年月
    try {
      Calendar min = Calendar.getInstance();
      Calendar max = Calendar.getInstance();

      min.setTime(sdf.parse(minDate));
      min.set(min.get(Calendar.YEAR), min.get(Calendar.MONTH), 1);

      max.setTime(sdf.parse(maxDate));
      max.set(max.get(Calendar.YEAR), max.get(Calendar.MONTH), 2);

      Calendar curr = min;
      while (curr.before(max)) {
        result.add(sdf.format(curr.getTime()));
        curr.add(Calendar.MONTH, 1);
      }

      // 实现排序方法
      Collections.sort(result, new Comparator<Object>() {
        @Override
        public int compare(Object o1, Object o2) {
          String str1 = (String) o1;
          String str2 = (String) o2;
          SimpleDateFormat format = new SimpleDateFormat("yyyy-MM");
          Date date1 = null;
          Date date2 = null;
          try {
            date1 = format.parse(str1);
            date2 = format.parse(str2);
          } catch (ParseException e) {
            e.printStackTrace();
          }

          if (date2.compareTo(date1) > 0) {
            return -1;
          }
          return 1;
        }
      });
    }catch (ParseException e) {
          e.printStackTrace();
      }
    
    return result;
  }
  
  public static void main(String[] args) {
    /*List<String> days = getDayBetween("2021-04-26", "2021-05-02");
    for (String day : days) {
      System.out.println(day);
    }*/
    
    List<String> monthBetween = getMonthBetween("2020-03", "2021-04");
    for (String month : monthBetween) {
      System.out.println(month);
    }
  }
}