SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
return sdf.format(new Date());
}
//前一天
public static String getYesterday(Date date) {
String tomorrow = "";
Calendar calendar = new GregorianCalendar();
calendar.setTime(date);
calendar.add(calendar.DATE, -1);
date = calendar.getTime();
SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd");
tomorrow = formatter.format(date);
return tomorrow;
}
//后一天
public static String getTomorrow(Date date) {
String tomorrow = "";
Calendar calendar = new GregorianCalendar();
calendar.setTime(date);
calendar.add(calendar.DATE, +1);
date = calendar.getTime();
SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd");
tomorrow = formatter.format(date);
return tomorrow;
}
//获取当前时间
public static String getNowTime() {
SimpleDateFormat sdf = new SimpleDateFormat("HH:mm:ss");
return sdf.format(new Date());
}
//获取当前日期(精确到毫秒)
public static String getNowTimeDetail() {
SimpleDateFormat sdf = new SimpleDateFormat("HH:mm:ss.SSS");
return sdf.format(new Date());
}
//获取今天是星期几
public static String getWeekOfDate(Date date) {
String[] weekDays = {"星期日", "星期一", "星期二", "星期三", "星期四", "星期五", "星期六"};
Calendar cal = Calendar.getInstance();
cal.setTime(date);
int w = cal.get(Calendar.DAY_OF_WEEK) - 1;
if (w < 0)
w = 0;
return weekDays[w];
}
//计算星期几
private static int getDayOfWeek(String dateTime) {
Calendar cal = Calendar.getInstance();
if (dateTime.equals("")) {
cal.setTime(new Date(System.currentTimeMillis()));
} else {
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd", Locale.getDefault());
Date date;
try {
date = sdf.parse(dateTime);
} catch (ParseException e) {
date = null;
e.printStackTrace();
}
if (date != null) {
cal.setTime(new Date(date.getTime()));
}
}
return cal.get(Calendar.DAY_OF_WEEK);
}
//根据年月日计算是星期几并与当前日期判断 非昨天、今天、明天 则以星期显示
public static String Week(String dateTime) {
String week = "";
String yesterday = "";
String today = "";
String tomorrow = "";
yesterday = getYesterday(new Date());
today = getNowDate();
tomorrow = getTomorrow(new Date());
if (dateTime.equals(yesterday)) {
week = "昨天";
} else if (dateTime.equals(today)) {
week = "今天";
} else if (dateTime.equals(tomorrow)) {
week = "明天";
} else {
switch (getDayOfWeek(dateTime)) {
case 1:
week = "星期日";
break;
case 2:
week = "星期一";
break;
case 3:
week = "星期二";
break;
case 4:
week = "星期三";
break;
case 5:
week = "星期四";
break;
case 6:
week = "星期五";
break;
case 7:
week = "星期六";
break;
}
}
return week;
}
//将时间戳转化为对应的时间(10位或者13位都可以)
public static String formatTime(long time) {
String times = null;
if (String.valueOf(time).length() > 10) {// 10位的秒级别的时间戳
times = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").format(new Date(time * 1000));
} else {// 13位的秒级别的时间戳
times = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").format(time);
}
return times;
}
//将时间字符串转为时间戳字符串
public static String getStringTimestamp(String time) {
String timestamp = null;
try {
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
Long longTime = sdf.parse(time).getTime() / 1000;
timestamp = Long.toString(longTime);
} catch (ParseException e) {
e.printStackTrace();
}
return timestamp;
}
}
| 日期时间格式 | 格式说明 |
| --- | --- |
| 小写的yyyy | 表示4位年份数字，如2010、2020等 |
| 大写的MM | 表示两位月份数字，如01表示一月份，12表示12月份 |
| 小写的dd | 表示两位日期数字，如09表示当月9号，26表示当月26号 |
| 大写的HH | 表示24小时制的两位小时数字，如22表示晚上10点 |
| 小写的hh | 表示12小时制的两位小时数字，如06可同时表示早上6点与傍晚6点，容易产生歧义所以实际开发中很少用 |
| 小写的mm | 表示两位分钟数字，如45表示某点45分 |
