DateUtils学习笔记

package com.study.commons;

import java.util.Calendar;
import java.util.Date;

import org.apache.commons.lang.time.DateFormatUtils;
import org.apache.commons.lang.time.DateUtils;

public class StudyDateUtils {
	
	public static void p (){
		System.out.println();
	}
	
	public static void p (Object obj){
		System.out.println(obj);
	}
	
	public static void main(String[] args) throws Exception {
		
		/**
		 * 下面几个属性都是以毫秒为单位的long类型
		 */
		p(DateUtils.MILLIS_PER_DAY);  //86400000 = 24 * 60 * 60 * 1000
		p(DateUtils.MILLIS_PER_HOUR); //3600000
		p(DateUtils.MILLIS_PER_MINUTE); //60000
		p(DateUtils.MILLIS_PER_SECOND); //1000
		
		p(DateUtils.RANGE_WEEK_SUNDAY); //1
		p(DateUtils.RANGE_WEEK_MONDAY); //2
		p(DateUtils.RANGE_WEEK_RELATIVE); //3
		p(DateUtils.RANGE_WEEK_CENTER); //4
		p(DateUtils.RANGE_MONTH_SUNDAY); //5
		p(DateUtils.RANGE_MONTH_MONDAY); //6
		p(DateUtils.SEMI_MONTH); //1001
		p(DateUtils.UTC_TIME_ZONE);	//	sun.util.calendar.ZoneInfo[id="GMT",offset=0,dstSavings=0,useDaylight=false,transitions=0,lastRule=null]
		
		/**
		 * 在Date基础上  增加1年
		 * 以此类推,下面就是增加年月日时分秒
		 */
		p(DateUtils.addYears(new Date(),1)); //Wed Aug 23 18:18:25 CST 2017
		p(DateUtils.addMonths(new Date(), 1)); //Fri Sep 23 18:20:38 CST 2016
		
		
		p(DateUtils.ceiling(new Date(), 1)); //Sun Jan 01 00:00:00 CST 2017  默认是年为单位向上去整年
		p(DateUtils.ceiling(new Date(), Calendar.HOUR)); //Wed Aug 24 12:00:00 CST 2016  以小时为单位,向上取整小时
		
		p(DateUtils.getFragmentInDays(new Date(), 1)); //237 默认就是以年为单位,取当前时间在今年的天数
		p(DateUtils.getFragmentInDays(new Date(), Calendar.MONTH)); //获取当前时间是这个月的第几天
		p(DateUtils.getFragmentInHours(new Date(), Calendar.DATE)); //获取当前是时间是当天的第几个小时
		
		p(DateUtils.isSameDay(new Date(), new Date()));//判断两个天数属否是同一天
		p(DateUtils.isSameInstant(new Date(), new Date())); //判断时间是否是同一个瞬间
		
		/**
		 * 将字符串转换成Date类型
		 */
		String[] str = {"HH:mm:ss","yyyy-MM-dd","yyyy-MM-dd HH:mm:ss"};
		p(DateUtils.parseDate("1992-10-25", str)); //Sun Oct 25 00:00:00 CST 1992
		p(DateUtils.parseDateStrictly("1992-10-25", str)); //Sun Oct 25 00:00:00 CST 1992
		
		p(DateUtils.round(new Date(), 1)); //Sun Jan 01 00:00:00 CST 2017 四舍五入去时间
		
		p(DateUtils.setDays(new Date(),25)); //Thu Aug 25 12:11:50 CST 2016 给当前时间设置新的天数
		
		p(DateUtils.toCalendar(new Date())); //将Date转换成日历类型
		
		p(DateUtils.truncate(new Date(),Calendar.HOUR)); //Wed Aug 24 12:00:00 CST 2016截取时间(取整)
		
		p(DateUtils.truncatedCompareTo(new Date(), DateUtils.addMinutes(new Date(), 41), Calendar.HOUR)); //对时间截取后比较大小
		
		p(DateUtils.truncatedEquals(new Date(), DateUtils.addMinutes(new Date(), 30), Calendar.HOUR)); //true
		
		/**
		 * DateFormatutils
		 */
		
		p(DateFormatUtils.format(DateUtils.toCalendar(new Date()), "yyyy-MM-dd")); //2016-08-24
		p(DateFormatUtils.format(new Date().getTime(), "yyyy-MM-dd")); //2016-08-24
	
		
		
		
		
	}

}