Calendar calendar=newGregorianCalendar();// 0可以修改,0代表当前时间,-1代表前一天
calendar.add(Calendar.DAY_OF_MONTH,0);//一天的开始时间 yyyy:MM:dd 00:00:00
calendar.set(Calendar.HOUR_OF_DAY,0);
calendar.set(Calendar.MINUTE,0);
calendar.set(Calendar.SECOND,0);
calendar.set(Calendar.MILLISECOND,0);Date dayStart= calendar.getTime();SimpleDateFormat simpleDateFormat=newSimpleDateFormat("yyyy-MM-dd HH:mm:ss");String startStr= simpleDateFormat.format(dayStart);//一天的结束时间 yyyy:MM:dd 23:59:59
calendar.set(Calendar.HOUR_OF_DAY,23);
calendar.set(Calendar.MINUTE,59);
calendar.set(Calendar.SECOND,59);
calendar.set(Calendar.MILLISECOND,999);Date dayEnd= calendar.getTime();
上面的是在java8之前的写法,当然在java8以后,有了localdatetime之后,写法也简单很多:
//获取当前时间LocalDateTime nowTime=LocalDateTime.now();//获取当前日期LocalDate nowDate=LocalDate.now();//设置零点LocalDateTime beginTime=LocalDateTime.of(nowDate,LocalTime.MIN);//将时间进行格式化Date start1=Date.from(beginTime.atZone(ZoneId.systemDefault()).toInstant());//设置当天的结束时间LocalDateTime endTime=LocalDateTime.of(nowDate,LocalTime.MAX);//将时间进行格式化Date end1=Date.from(endTime.atZone(ZoneId.systemDefault()).toInstant());