一個完整的日期實現類
package com.nyhr.util;
import java.util.GregorianCalendar;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Locale;
import java.util.Calendar;
/**
?* <p>Title: 日期時間處理</p>
?* <p>Description: 工具類</p>
?* <p>Copyright: Copyright (c) 2005</p>
?* <p>
?* @version 1.0
?* @author?
?*/
public class DateUtil
{
??? /**
???? * 缺省的DateFormat對象，可以將一個java.util.Date格式化成yyyy-mm-dd輸出
???? */
??? private static DateFormat df = DateFormat.getDateInstance(DateFormat.MEDIUM, Locale.SIMPLIFIED_CHINESE);
??? /**
???? * 私有構造函數
???? */
??? private DateUtil()
??? {
??? }
??? /**
???? * <p>返回一個當前的時間，并按格式轉換為字符串</p>
???? * 例：17:27:03
???? * @return String
???? */
??? public static String getNowTime()
??? {
??????? GregorianCalendar gcNow = new GregorianCalendar();
??????? java.util.Date dNow = gcNow.getTime();
??????? DateFormat df = DateFormat.getTimeInstance(DateFormat.MEDIUM, Locale.SIMPLIFIED_CHINESE);
??????? return df.format(dNow);
??? }
??? /**
???? * <p>返回一個當前日期，并按格式轉換為字符串</p>
???? * 例：2004-4-30
???? * @return String
???? */
??? public static String getNowDate()
??? {
??????? GregorianCalendar gcNow = new GregorianCalendar();
??????? java.util.Date dNow = gcNow.getTime();
??????? DateFormat df = DateFormat.getDateInstance(DateFormat.MEDIUM, Locale.SIMPLIFIED_CHINESE);
??????? return df.format(dNow);
??? }
??? /**
???? * <p>返回一個當前日期和時間，并按格式轉換為字符串</p>
???? * 例：2004-4-30 17:27:03
???? * @return String
???? */
??? public static String getNowDateTime()
??? {
??????? GregorianCalendar gcNow = new GregorianCalendar();
??????? java.util.Date dNow = gcNow.getTime();
??????? DateFormat df = DateFormat.getDateTimeInstance(DateFormat.MEDIUM, DateFormat.MEDIUM, Locale.SIMPLIFIED_CHINESE);
??????? return df.format(dNow);
??? }
??? /**
???? * <p>返回當前年</p>
???? * @return int
???? */
??? public static int getThisYear()
??? {
??????? GregorianCalendar gcNow = new GregorianCalendar();
??????? return gcNow.get(GregorianCalendar.YEAR);
??? }
??? /**
???? * 返回本月
???? * @return int
???? */
??? public static int getThisMonth()
??? {
??????? GregorianCalendar gcNow = new GregorianCalendar();
??????? return gcNow.get(GregorianCalendar.MONTH) + 1;
??? }
??? /**
???? * 返回今天是本月的第幾天
???? * @return int 從1開始
???? */
??? public static int getToDayOfMonth()
??? {
??????? GregorianCalendar gcNow = new GregorianCalendar();
??????? return gcNow.get(GregorianCalendar.DAY_OF_MONTH);
??? }
??? /**
???? * 返回當前的小時
???? * @return int
???? */
??? public static int getHour()
??? {
??? ? GregorianCalendar gcNow = new GregorianCalendar();
???????? return gcNow.get(GregorianCalendar.HOUR);
??? }
??? /**
???? * 返回當前的分鐘
???? * @return int 返回當前的分鐘
???? */
??? public static int getMinute()
??? {
??? ? GregorianCalendar gcNow = new GregorianCalendar();
???????? return gcNow.get(GregorianCalendar.MINUTE);
??? }
??? /**
???? * 返回當前的秒數
???? * @return int 第幾秒
???? */
??? public static int getSecond()
??? {
??? ? GregorianCalendar gcNow = new GregorianCalendar();
???????? return gcNow.get(GregorianCalendar.SECOND);
??? }
??? /**
???? * 返回今天是本年的第幾周
???? * @return int 從1開始
???? */
????
??? public static int getToWeekOfYear()
??? {
??? ?GregorianCalendar gcNow = new GregorianCalendar();
??? ?return gcNow.get(GregorianCalendar.WEEK_OF_YEAR);
??? }
??? /**
???? * 返回一格式化的日期
???? * @param time long
???? * @return String yyyy-mm-dd 格式
???? */
??? public static String formatDate(java.util.Date date)
??? {
??????? if (date == null) return "";
??????? else return df.format(date);
??? }
??? /**
???? * 返回一格式化的日期
???? * @param time long
???? * @return String 2005-6-17 格式
???? */
??? public static String formatSDate(java.util.Date date)
??? {
??????? if (date == null) return "";
??????? else
??????? {
??????????? SimpleDateFormat bartDateFormat = new SimpleDateFormat("yyyy-M-d HH:mm:ss");
??????????? return bartDateFormat.format(date);
??????? }
??? }
??? /**
???? * 返回已添加指定時間間隔的日期
???? * @param interval? 表示要添加的時間間隔("y":年;"d":天;"m":月;如有必要可以自行增加)
???? * @param number??? 表示要添加的時間間隔的個數
???? * @param date????? java.util.Date()
???? * @return String?? 2005-5-12格式的日期字串
???? */
??? public static String dateAdd(String interval, int number,
??????????? java.util.Date date)
??? {
??????? String strTmp = "";
??????? GregorianCalendar gc = new GregorianCalendar();
??????? gc.setTime(date);
??????? //加若干年
??????? if (interval.equals("y"))
??????? {
??????????? int currYear = gc.get(Calendar.YEAR);
??????????? gc.set(Calendar.YEAR, currYear + number);
??????? }
??????? //加若干月
??????? else if (interval.equals("m"))
??????? {
??????????? int currMonth = gc.get(Calendar.MONTH);
??????????? gc.set(Calendar.MONTH, currMonth + number);
??????? }
??????? //加若干天
??????? else if (interval.equals("d"))
??????? {
??????????? int currDay = gc.get(Calendar.DATE);
??????????? gc.set(Calendar.DATE, currDay + number);
??????? }
??????? //加若小時
??????? else if (interval.equals("h"))
??????? {
??????????? int currDay = gc.get(Calendar.HOUR);
??????????? gc.set(Calendar.HOUR, currDay + number);
??????? }
??????? SimpleDateFormat bartDateFormat = new SimpleDateFormat("yyyy-M-d HH:mm:ss");
??????? strTmp = bartDateFormat.format(gc.getTime());
??????? return strTmp;
??? }
??? /**
???? * <p>返回兩個日期之間的單位間隔數</p>
???? * @param a java.util.Date
???? * @param b java.util.Date
???? * @return int 間隔數
???? */
??? public static int dateDiff(java.util.Date a, java.util.Date b)
??? {
??????? int tempDifference = 0;
??????? int difference = 0;
??????? Calendar earlier = Calendar.getInstance();
??????? Calendar later = Calendar.getInstance();
??????? if (a.compareTo(b) < 0)
??????? {
??????????? earlier.setTime(a);
??????????? later.setTime(b);
??????? }
??????? else
??????? {
??????????? earlier.setTime(b);
??????????? later.setTime(a);
??????? }
??????? while (earlier.get(Calendar.YEAR) != later.get(Calendar.YEAR))
??????? {
??????????? tempDifference = 365 * (later.get(Calendar.YEAR) - earlier.get(Calendar.YEAR));
??????????? difference += tempDifference;
??????????? earlier.add(Calendar.DAY_OF_YEAR, tempDifference);
??????? }
??????? if (earlier.get(Calendar.DAY_OF_YEAR) != later.get(Calendar.DAY_OF_YEAR))
??????? {
??????????? tempDifference = later.get(Calendar.DAY_OF_YEAR)
??????????????????? - earlier.get(Calendar.DAY_OF_YEAR);
??????????? difference += tempDifference;
??????????? earlier.add(Calendar.DAY_OF_YEAR, tempDifference);
??????? }
??????? return difference;
??? }
/**
???? * <p>該方法是獲得到每月1號星期一的數據</p>
???? * @return?-返回一個數字
???? */
??? /**
???? * <p>該方法是獲得到每月1號星期一的數據</p>
???? * @return?-返回一個數字
???? */
??? public static int getDate(int curYear,int curMonth ,int curDate)
??? {
??? ?int day1 = 0;
??? ?Calendar cal = Calendar.getInstance();
??? ?cal.clear();
??? ?cal.set(curYear,curMonth-1,curDate);
??? ?int dayOfWeek = cal.get(cal.DAY_OF_WEEK);???? ?
??? ?System.out.println("curDate="+curDate +" dayOfWeek "+dayOfWeek);
??? ?switch(dayOfWeek)
??? ?{
??? ??case 1:???//星期天
??? ???day1=0;
??? ???break;
??? ??case 2:???//星期一
??? ???day1=1;
??? ???break;
??? ??case 3:???//星期二
??? ???day1=2;
??? ???break;
??? ??case 4:???//星期三
??? ???day1=3;
??? ???break;
??? ??case 5:???//星期四
??? ???day1=4;
??? ???break;
??? ??case 6:???//星期五
??? ???day1=5;
??? ???break;
??? ??case 7:???//星期六
??? ???day1=6;
??? ???break;
??? ?}??
??? ?return day1;
??? }
??? public static String checkTime(int id)
??? {
??????? String bol = "";
??????? Calendar tt = Calendar.getInstance();?????
??????? String currDate=getNowDate();???
?????? System.out.println("currDate="+currDate);
??????? int result = tt.get(Calendar.DAY_OF_WEEK);
?
??????? int shour = tt.get(Calendar.HOUR_OF_DAY);
???????
??????? if (id == 3)
??????? {
??????????? switch (result)
??????????? {
??????????????? case 1:
??????????????????? break;
??????????????? case 7:
??????????????????? if ((shour >= 8) && (shour < 12))
??????????????????? {
??????????????????????? bol = "disabled";
??????????????????????? break;
??????????????????? }
??????????????? default:
??????????????????? if ((shour >= 8) && (shour < 12))
??????????????????? {
??????????????????????? bol = "disabled";
??????????????????????? break;
??????????????????? }
??????????????????? else if ((shour >= 14) && (shour < 17))
??????????????????? {
??????????????????????? bol = "disabled";
??????????????????????? break;
??????????????????? }
??????????? }
??????? }
??????? return bol;
??? }
??? /**
???? * <p>該方法是將字符型轉變成日期型</p>
???? * @param strX -傳入字符類型
???? * @return -返回日期類型
???? */
??? public static Date getStrDate(String strX)
??? {
??? ?Date date1=new Date();
??? ?if (!strX.equals(""))
??? ?{
??? ??try
??? ??{
??? ???date1=(DateFormat.getDateInstance()).parse(strX);
??? ??}
??? ??catch(Exception ex)
??? ??{
??? ???Debug.log("hhh","getStrDate()",ex.toString());
??? ???//System.out.println(ex.toString());
??? ??}
??? ?}
??? ?else
??? ?{
??? ?? GregorianCalendar gcNow = new GregorianCalendar();
??? ?????? date1 = gcNow.getTime();
??? ?}
??? ?
??? ?return date1;
??? }
???
??? /**
???? * <p>比較兩日期字符串的大小</p>
???? * @param d1
???? * @param d2
???? * @return (d1>d2)?2:(d1=d2)?1:0
???? */
??? public static int compareDate(String d1, String d2)
??? {
??? ?short vl = 1;
??? ?GregorianCalendar gc = new GregorianCalendar();
??????? gc.setTime(getStrDate(d1));
??????? int year = gc.get(GregorianCalendar.YEAR);
??????? int month = gc.get(GregorianCalendar.MONTH);
??????? int day = gc.get(GregorianCalendar.DAY_OF_MONTH);
??????? gc.setTime(getStrDate(d2));
??????? int tempYear = gc.get(GregorianCalendar.YEAR);
??????? int tempMonth = gc.get(GregorianCalendar.MONTH);
??????? int tempDay = gc.get(GregorianCalendar.DAY_OF_MONTH);
??????? if(year !=? tempYear)
??????? {
??????? ?if (year>tempYear)
??????? ??vl = 2;
??????? ?else
??????? ??vl = 0;
??????? }
??????? else
??????? {
??????? ?if (month != tempMonth)
??????? ?{
??????? ??if(month>tempMonth)
??????? ???vl = 2;
??????? ??else
??????? ???vl = 0;
??????? ?}
??????? ?else
??????? ?{
??????? ??if (day != tempDay)
??????? ??{
??????? ???if (day > tempDay)
??????? ????vl = 2;
??????????? ??else
??????????? ???vl = 0;
??????? ??}
??????? ?}
??????? }
??????? return vl;
??? }
???
}