java 判断两个时间段是否重叠的案例

package com.abc.common.util;

import lombok.Data;
import org.springframework.stereotype.Component;

import java.time.LocalDateTime;

/**
 * 日期工具类
 * <p>
 *   使用LocalDateTime存取或判断
 * </p>
 * @see java.time.LocalDateTime
 * @date 2020-6-29 10:20:42
 */
@Component
public class DateUtil {

  /**
   * 判断两个时间段是否重叠
   * @param slot1
   * @param slot2
   * @return
   */
  public static boolean overlapped(TimeSlot slot1, TimeSlot slot2) {
    TimeSlot previous, next;
    previous = slot1.startTime.isBefore(slot2.startTime) ? slot1 : slot2;
    next = slot2.startTime.isAfter(slot1.startTime) ? slot2 : slot1;
    // 这里业务需要，允许时间点的重叠
    // 例如某个时间段的起始时间：2020-06-29 00:00:00
    // 和另一个时间段的终止时间：2020-06-29 00:00:00
    // 它们俩可以有交点。如果不需要这种逻辑只把le改成lt
    // ，ge改成gt就可
    return !(le(previous, next) || ge(previous, next));
  }

  /**
   * 构造一个时间段
   * @param startTime
   * @param endTime
   * @return
   */
  public static TimeSlot buildSlot(LocalDateTime startTime, LocalDateTime endTime) {
    return new TimeSlot(startTime, endTime);
  }

  /**
   * less equal
   * 小于等于
   * @param prev
   * @param next
   * @return
   */
  private static boolean le(TimeSlot prev, TimeSlot next) {
    return lt(prev, next) || next.endTime.isEqual(prev.startTime);
  }

  /**
   * greater equal
   * 大于等于
   * @param prev
   * @param next
   * @return
   */
  private static boolean ge(TimeSlot prev, TimeSlot next) {
    return gt(prev, next) || prev.endTime.isEqual(next.startTime);
  }

  /**
   * greater than
   * 大于
   * @param prev
   * @param next
   * @return
   */
  private static boolean gt(TimeSlot prev, TimeSlot next) {
    return prev.endTime.isBefore(next.startTime);
  }

  /**
   * less than
   * 小于
   * @param prev
   * @param next
   * @return
   */
  private static boolean lt(TimeSlot prev, TimeSlot next) {
    return next.endTime.isBefore(prev.startTime);
  }

  /**
   * 时间段类
   */
  @Data
  static class TimeSlot{
    private LocalDateTime startTime;
    private LocalDateTime endTime;

    public TimeSlot(LocalDateTime startTime, LocalDateTime endTime) {
      if (startTime.isAfter(endTime)) {
        this.startTime = endTime;
        this.endTime = startTime;
      } else {
        this.startTime = startTime;
        this.endTime = endTime;
      }
    }
  }
}

// ...
 if (DateUtil.overlapped(
 DateUtil.buildSlot(beginTime, endTime),
 DateUtil.buildSlot(beginTime1, endTime1)
 )) {
 // 时间段有重叠，写下重叠情况的业务代码
 }
// ...

 public static String TimeDifference(long start, long end) {
 
    long between = end - start;
    long day = between / (24 * 60 * 60 * 1000);
    long hour = (between / (60 * 60 * 1000) - day * 24);
    long min = ((between / (60 * 1000)) - day * 24 * 60 - hour * 60);
    long s = (between / 1000 - day * 24 * 60 * 60 - hour * 60 * 60 - min * 60);
    long ms = (between - day * 24 * 60 * 60 * 1000 - hour * 60 * 60 * 1000
        - min * 60 * 1000 - s * 1000);
    String timeDifference = day + "天" + hour + "小时" + min + "分" + s + "秒" + ms
        + "毫秒";
    return timeDifference;
  }