java中日期处理的一些工具方法

大家好，我是雄雄，欢迎关注微信公众号：雄雄的小课堂

前言

现在是2022年4月16日15:35:14！忙里偷闲，直接来看方法吧，写完文章继续去改Bug:

1.计算两个日期之间相差的天数

/**
   * @param stratTime 开始时间
   * @param endTime 结束时间
   * @return 计算两个日期之间相差的天数
   */
  public static Map<String, Object> dateDiff(Long stratTime, Long endTime) {
    Map<String, Object> map = new HashMap<>();
    Long diff = endTime - stratTime;
    Long day = diff / (24 * 60 * 60 * 1000);
    Long hour = (diff / (60 * 60 * 1000) - day * 24);
    Long min = ((diff / (60 * 1000)) - day * 24 * 60 - hour * 60);
    Long sec = (diff / 1000 - day * 24 * 60 * 60 - hour * 60 * 60 - min * 60);
    map.put("day", day);
    map.put("hour", hour);
    map.put("min", min);
    map.put("sec", sec);
    return map;
  }

2.将时间戳转换成时间

/**
   * 将时间戳转换成时间
   */
  public static Map<String, Object> formatTime(Long time) {
    Map<String, Object> map = new HashMap<>();
    Long day = time / (24 * 60 * 60 * 1000);
    Long hour = (time / (60 * 60 * 1000) - day * 24);
    Long min = ((time / (60 * 1000)) - day * 24 * 60 - hour * 60);
    Long sec = (time / 1000 - day * 24 * 60 * 60 - hour * 60 * 60 - min * 60);
    map.put("day", day);
    map.put("hour", hour);
    map.put("min", min);
    map.put("sec", sec);
    return map;
  }

3. 获取当前24小时的时间前后时间戳

/**
   * 将时间戳转换成时间
   */
    public static Map<String, Object> getTimeChuo() {
      Map<String, Object> map = new HashMap<>();
      Long nowTime = System.currentTimeMillis();
      Long startTime = nowTime - 24 * 60 * 60 * 1000;
      Long endTime = nowTime + 24 * 60 * 60 * 1000;
      map.put("startTime", startTime);
      map.put("endTime", endTime);
    return map;
  }

4.由出生日期获得年龄

public static int getAge(Date birthDay) throws Exception {
    Calendar cal = Calendar.getInstance();
    if (cal.before(birthDay)) {
      throw new IllegalArgumentException("出生日期小于当前时间，无效的日期!");
    }
    int yearNow = cal.get(Calendar.YEAR);
    int monthNow = cal.get(Calendar.MONTH);
    int dayOfMonthNow = cal.get(Calendar.DAY_OF_MONTH);
    cal.setTime(birthDay);

    int yearBirth = cal.get(Calendar.YEAR);
    int monthBirth = cal.get(Calendar.MONTH);
    int dayOfMonthBirth = cal.get(Calendar.DAY_OF_MONTH);

    int age = yearNow - yearBirth;

    if (monthNow <= monthBirth) {
      if (monthNow == monthBirth) {
        if (dayOfMonthNow < dayOfMonthBirth) age--;
      } else {
        age--;
      }
    }
    return age;
  }

5.统计两个日期之间的所有日期

/**
   * 统计两个日期之间的所有日期
   */
  public static List<String> getBeginTimeAndEndTime(Date beginTime, Date endTime) {
    List<String> listDate = new ArrayList<>();
    SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");
    try {
      Calendar calendar = Calendar.getInstance();
      calendar.setTime(beginTime);
      while (calendar.getTime().before(endTime) || calendar.getTime().equals(endTime)) {
        listDate.add(dateFormat.format(calendar.getTime()));
        calendar.add(Calendar.DAY_OF_MONTH, 1);
      }
      return listDate;
    } catch (Exception e) {
      e.printStackTrace();
    }
    return listDate;
  }

6.根据生日获取年龄的另一种方法

/**
   * 根据日期获取年龄
   */
  public static int getAgeByDate(Date date) throws Exception {
    Calendar cal = Calendar.getInstance();
    int thisYear = cal.get(Calendar.YEAR);
    int thisMonth = cal.get(Calendar.MONTH);
    int dayOfMonth = cal.get(Calendar.DAY_OF_MONTH);
    cal.setTime(date);
    int birthYear = cal.get(Calendar.YEAR);
    int birthMonth = cal.get(Calendar.MONTH);
    int birthdayOfMonth = cal.get(Calendar.DAY_OF_MONTH);

    int age = thisYear - birthYear;

    // 未足月
    if (thisMonth <= birthMonth) {
      // 当月
      if (thisMonth == birthMonth) {
        // 未足日
        if (dayOfMonth < birthdayOfMonth) {
          age--;
        }
      } else {
        age--;
      }
    }
    return age;
  }