Java tutorial
/** * Copyright © 2012-2013 <a href="https://github.com/thinkgem/jeesite">JeeSite</a> All rights reserved. * * Licensed under the Apache License, Version 2.0 (the "License"); */ package com.tinypace.mobistore.util; import java.text.ParseException; import java.text.SimpleDateFormat; import java.util.Calendar; import java.util.Date; import org.apache.commons.lang3.time.DateFormatUtils; /** * , org.apache.commons.lang.time.DateUtils * @author ThinkGem * @version 2013-3-15 */ public class DateUtils extends org.apache.commons.lang3.time.DateUtils { private static String[] parsePatterns = { "yyyy-MM-dd", "yyyy-MM-dd HH:mm:ss", "yyyy-MM-dd HH:mm", "yyyy/MM/dd", "yyyy/MM/dd HH:mm:ss", "yyyy/MM/dd HH:mm" }; /** * ? * * @param d * @param day * @return */ public static Date getDateBefore(Date d, int day) { Calendar cal = Calendar.getInstance(); cal.setTime(d); cal.set(Calendar.DATE, cal.get(Calendar.DATE) - day); return cal.getTime(); } /** * ? * * @param d * @param day * @return */ public static Date getDateAfter(Date d, int day) { Calendar cal = Calendar.getInstance(); cal.setTime(d); cal.set(Calendar.DATE, cal.get(Calendar.DATE) + day); return cal.getTime(); } /** * ? ?yyyy-MM-dd */ public static String getDate() { return getDate("yyyy-MM-dd"); } /** * ? ?yyyy-MM-dd pattern?"yyyy-MM-dd" "HH:mm:ss" "E" */ public static String getDate(String pattern) { return DateFormatUtils.format(new Date(), pattern); } /** * ?yyyy-MM-dd pattern?"yyyy-MM-dd" "HH:mm:ss" "E" */ public static String formatDate(Date date, Object... pattern) { String formatDate = null; if (pattern != null && pattern.length > 0) { formatDate = DateFormatUtils.format(date, pattern[0].toString()); } else { formatDate = DateFormatUtils.format(date, "yyyy-MM-dd"); } return formatDate; } /** * ??yyyy-MM-dd HH:mm:ss */ public static String formatDateTime(Date date) { return formatDate(date, "yyyy-MM-dd HH:mm:ss"); } /** * ? ?HH:mm:ss */ public static String getTime() { return formatDate(new Date(), "HH:mm:ss"); } /** * ? ?yyyy-MM-dd HH:mm:ss */ public static String getDateTime() { return formatDate(new Date(), "yyyy-MM-dd HH:mm:ss"); } /** * ? ?yyyy */ public static String getYear() { return formatDate(new Date(), "yyyy"); } /** * ? ?MM */ public static String getMonth() { return formatDate(new Date(), "MM"); } /** * ?dd */ public static String getDay() { return formatDate(new Date(), "dd"); } /** * ? ?E */ public static String getWeek() { return formatDate(new Date(), "E"); } /** * ? * { "yyyy-MM-dd", "yyyy-MM-dd HH:mm:ss", "yyyy-MM-dd HH:mm", * "yyyy/MM/dd", "yyyy/MM/dd HH:mm:ss", "yyyy/MM/dd HH:mm" } */ public static Date parseDate(Object str) { if (str == null) { return null; } try { return parseDate(str.toString(), parsePatterns); } catch (ParseException e) { return null; } } /** * ? * @param date * @return */ public static long pastDays(Date date) { long t = new Date().getTime() - date.getTime(); return t / (24 * 60 * 60 * 1000); } public static Date getDateStart(Date date) { if (date == null) { return null; } SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"); try { date = sdf.parse(formatDate(date, "yyyy-MM-dd") + " 00:00:00"); } catch (ParseException e) { e.printStackTrace(); } return date; } public static Date getDateEnd(Date date) { if (date == null) { return null; } SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"); try { date = sdf.parse(formatDate(date, "yyyy-MM-dd") + " 23:59:59"); } catch (ParseException e) { e.printStackTrace(); } return date; } /** * @param args * @throws ParseException */ public static void main(String[] args) throws ParseException { // System.out.println(formatDate(parseDate("2010/3/6"))); // System.out.println(getDate("yyyyMMdd E")); // long time = new Date().getTime()-parseDate("2012-11-19").getTime(); // System.out.println(time/(24*60*60*1000)); } }