秒数差 < 60*60 (即60分钟) => 秒数差/60 分钟前
秒数差 < 60
60
24 (即24小时内) => 秒数差/60*60 小时前
秒数差 >60
60
24 (即24小时内) => 转localDateTime 后再格式化输出 【SimpleDateFormat多线程不安全】
转换成代码如下：
为了操作方便，也避免计算出错，这里将各个时间单位转换为秒数定义为静态常量，并且使用DateTimFormatter格式化保证多线程安全，如下：
封装DateUtil工具类
import java.time.LocalDateTime;
import java.time.ZoneId;
import java.time.format.DateTimeFormatter;
import java.util.Date;
* @Author: lzp
* @description:
* @Date: 2022/8/6
public class DateUtils {
* 一天、一分钟、一小时对应的秒数
private static final Long ONE_MINUTE_TO_SECOND = 60L;
private static final Long ONE_HOUR_TO_SECOND = ONE_MINUTE_TO_SECOND * 60;
private static final Long ONE_DAY_TO_SECOND = ONE_HOUR_TO_SECOND * 24;
* 使用LocalDateTime进行格式化 保证多线程安全
private static final DateTimeFormatter DATE_TIME_FORMATTER1 = DateTimeFormatter.ofPattern("yyyy-MM-dd");
private static final DateTimeFormatter DATE_TIME_FORMATTER2 = DateTimeFormatter.ofPattern("MM-dd");
* 设置推送消息的时间描述
* 1. 1分钟内：刚刚
* 2. 60分钟内：x分钟前
* 3. 24小时内：x小时前
* 4. >24小时：x月x日 08-1
* 5. 非年内：年-月-日 2021-05-02
* @param now 当前时间 传一个当前时间目的是方便遍历，减少date对象的创建
* @param targetDate 与当前时间做对比的时间
public static String getTimeDescriptionByDate(Date now, Date targetDate) {
String timeDescription = "";
if (targetDate != null) {
if (targetDate.getYear() == now.getYear()) {
long betweenSeconds = (now.getTime() - targetDate.getTime()) / 1000;
if (betweenSeconds < ONE_MINUTE_TO_SECOND) {
timeDescription = "刚刚";
} else if (betweenSeconds < ONE_HOUR_TO_SECOND) {
timeDescription = betweenSeconds / ONE_MINUTE_TO_SECOND + "分钟前";
} else if (betweenSeconds < ONE_HOUR_TO_SECOND * 24) {
timeDescription = betweenSeconds / ONE_HOUR_TO_SECOND + "小时前";
} else {
timeDescription = dateToLocalDateTime(targetDate).format(DATE_TIME_FORMATTER2);
} else {
timeDescription = dateToLocalDateTime(targetDate).format(DATE_TIME_FORMATTER1);
return timeDescription;
* date转localDateTime
public static LocalDateTime dateToLocalDateTime(Date date) {
return date.toInstant().atZone(ZoneId.systemDefault()).toLocalDateTime();
测试类，直接运行即可，能够自动按照当前时间显示对应的描述：
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
* @Author: lzp
* @description:
* @Date: 2022/8/6
public class Demo {
public static void main(String[] args) throws ParseException {
SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
Date now = new Date();
Calendar cal = Calendar.getInstance();
cal.setTime(now);
System.out.printf("当前时间为：%s ==============================\n", df.format(now));
cal.add(Calendar.SECOND, -20);
System.out.printf("%s => %s\n", df.format(cal.getTime()), DateUtils.getTimeDescriptionByDate(now, cal.getTime()));
cal.add(Calendar.MINUTE, -1);
System.out.printf("%s => %s\n", df.format(cal.getTime()), DateUtils.getTimeDescriptionByDate(now, cal.getTime()));
cal.add(Calendar.HOUR, -1);
System.out.printf("%s => %s\n", df.format(cal.getTime()), DateUtils.getTimeDescriptionByDate(now, cal.getTime()));
cal.add(Calendar.DAY_OF_MONTH, -1);
System.out.printf("%s => %s\n", df.format(cal.getTime()), DateUtils.getTimeDescriptionByDate(now, cal.getTime()));
cal.add(Calendar.YEAR, -1);
System.out.printf("%s => %s\n", df.format(cal.getTime()), DateUtils.getTimeDescriptionByDate(now, cal.getTime()));
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