1、获取前一天目前的时间
(方式一) Date date = new Date(); long now = date.getTime(); long yesterday = now - 24*60*60*1000; SimpleDateFormate formate = new SimpleDateFormate("yyyy-MM-dd HH:mm:ss"); System.out.println(formate.formate(yesterday)); (方式二) Calendar calendar =Calendar.getInstance(); calendar.add(Calendar.DAY_OF_YEAR,-1); System.out.println(formate.formate(calendar.getTime()));2、给出指定日期,转换成毫秒
String time = "2017-06-06 16:26:28"; SimpleDateFormate formate = new SimpleDateFormate("yyyy-MM-dd HH:mm:ss"); try { long now = format.parse(time).getTime(); System.out.println(now); } catch (ParseException e) { e.printStackTrace(); }3、比较两个日期
String time1 = "2017-06-06"; String time2 = "2017-06-08"; SimpleDateFormate formate = new SimpleDateFormate("yyyy-MM-dd"); try { Date date1 = format.parse(time1); Date date2 = format.parse(time2); if(date1.equals(date2)){ System.out.println("equals"); }else if(date1.before(date2)){ System.out.println("before"); }else{ System.out.println("after"); } } catch (ParseException e) { e.printStackTrace(); }4、获取日期为所在星期中的第几日
Calendar calendar = Calendar.getInstance(); calendar.get(Calendar.MONTH); calendar.get(Calendar.YEAR); calendar.get(Calendar.DAY_OF_MONTH);