bsp see mini ngs time edate 构造方法 area
涉及的一些api:
Calendar calendar = Calendar.getInstance();
calendar.getTime();
calendar.setTime(date);
calendar.set(Calendar.YEAR,2000);
calendar.get(Calendar.DATE);
calendar.add(Calendar.DAY_OF_YEAR, 10);
calendar.getActualMaximum(Calendar.DAY_OF_MONTH);
calendar1.after(calendar2);
calendar.getTimeInMillis();
SimpleDateFormat sdf = new SimpleDateFormat();
sdf.parse();
sdf.format();
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss E");
String strTime = sdf.format(date);
date = sdf.parse(strTime);
举例及说明如下代码:
- package test;
- import java.text.ParseException;
- import java.text.SimpleDateFormat;
- import java.util.Calendar;
- import java.util.Date;
- public class DateDemo {
- public static void main(String[] args) throws ParseException {
- Date date = new Date();
- //当前时间毫秒值,long类型
- long numTime = date.getTime();
- System.out.println(numTime);
- //以"yyyy-MM-dd HH:mm:ss E" 格式 构造SimpleDateFormat的对象
- SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss E");
- // 根据Date类型对象 生成sdf中的格式(构造方法中指定了)的字符串时间
- String strTime = sdf.format(date);
- System.out.println(strTime);
- //从字符串strTime 以sdf中的格式(构造方法中指定了) 生成 Date类型对象
- date = sdf.parse(strTime);
- System.out.println(date);
- //Calendar是抽象类,不能直接new生成
- Calendar calendar = Calendar.getInstance();
- Calendar calendar2 = calendar;
- System.out.println(calendar); //直接这样输出的看不懂,java.util.GregorianCalendar[time=1504450592066,areFieldsSet=true,areAllFieldsSet=true,lenient=true,zone=sun.util.calendar.ZoneInfo[id="GMT+08:00",offset=28800000,dstSavings=0,useDaylight=false,transitions=0,lastRule=null],firstDayOfWeek=1,minimalDaysInFirstWeek=1,ERA=1,YEAR=2017,MONTH=8,WEEK_OF_YEAR=36,WEEK_OF_MONTH=2,DAY_OF_MONTH=3,DAY_OF_YEAR=246,DAY_OF_WEEK=1,DAY_OF_WEEK_IN_MONTH=1,AM_PM=1,HOUR=10,HOUR_OF_DAY=22,MINUTE=56,SECOND=32,MILLISECOND=66,ZONE_OFFSET=28800000,DST_OFFSET=0]
- //获得date对象
- date = calendar.getTime();
- //将date中时间设置给calendar
- calendar.setTime(date);
- //获取
- calendar.get(Calendar.YEAR);
- //设置
- calendar.set(Calendar.MONTH, 0);
- //增加
- calendar.add(Calendar.DAY_OF_YEAR, 10);
- //指定日历字段可能拥有的最大值。在此句中指当前月份的最大天数。
- calendar.getActualMaximum(Calendar.DAY_OF_MONTH);
- //boolean类型,判断calendar1的时间是否在calendar2之后
- calendar.after(calendar2);
- //获得毫秒值,返回long类型
- calendar.getTimeInMillis();
- }
- }
java笔记------日期API
来源: http://www.bubuko.com/infodetail-2290913.html