日期处理类

package com.cmp.yiwu.util;

import java.util.Calendar;
import java.sql.Date;
import java.text.*;
import java.sql.Time;
import java.sql.Timestamp;

/**
 * <p>Copyright: Copyright (c) 2006</p>
 * <p>Company: Norteksoft</p>
 * @author 
 * @version 1.0
 */

public class DateUtil {
  public DateUtil() {
  }

  public static String getCurrentDate() {
    String currentDate = null;

    String yyyy = Long.toString(Calendar.getInstance().get(Calendar.YEAR));

    String mm = Long.toString(Calendar.getInstance().get(Calendar.MONTH) + 1);
    if (mm.length() == 1) {
      mm = "0" + mm;
    }

    String dd = Long.toString(Calendar.getInstance().get(Calendar.DAY_OF_MONTH));
    if (dd.length() == 1) {
      dd = "0" + dd;
    }
    currentDate = yyyy + "-" + mm + "-" + dd;
    return currentDate;
  }
public static Date getNowDate()
{
  return Date.valueOf(getCurrentDate());
}
  public static String getCurrentTime() {

    int h = Calendar.getInstance().get(Calendar.HOUR);
    String hour = Long.toString(h);

    if (h > 12) {
      hour = "上午";
      h = h - 12;
    }
    else if (h < 12) {
      hour = "下午";

    }
    else {
      hour = "中午";
    }

    hour += Long.toString(h) + "点";

    int m = Calendar.getInstance().get(Calendar.MINUTE);
    String minute = Long.toString(m) + "分";

    int s = Calendar.getInstance().get(Calendar.SECOND);
    String second = Long.toString(s) + "秒";

    String currentTime = hour + ":" + minute + ":" + second;

    return currentTime;
  }

  public static String getCurrentDateAndTime() {
    String date = getCurrentDate();
    String time = getCurrentTime();

    return date + " " + time;

  }

private static String[][] timeZoneList = null;
private static Object timeZoneLock = new Object();

public static final long SECOND = 1000;
public static final long MINUTE = 60 * SECOND;
public static final long HOUR = 60 * MINUTE;
public static final long DAY = 24 * HOUR;
public static final long WEEK = 7 * DAY;

//由java.util.Date到java.sql.Date的类型转换
public static java.sql.Date getSqlDate(java.util.Date date) {
  return new java.sql.Date(date.getTime());
}

//返回一个日期字符串在星期中的顺序
public static int getDateInWeek(String strDate) {
  DateFormat df = DateFormat.getDateInstance();
  try {
    df.parse(strDate);
    java.util.Calendar c = df.getCalendar();
    int day = c.get(c.DAY_OF_WEEK) - c.SUNDAY;
    return day;
  }
  catch (ParseException e) {
    return -1;
  }
}

//一个日期上加天数
public static String DateAdd(String startDate, int dd) {
  java.text.DateFormat df = java.text.DateFormat.getDateInstance();
  java.util.Date date = new java.util.Date();
  try {
    date = df.parse(startDate);
  }
  catch (Exception ex) {
    System.out.print(ex);
  }

  Calendar calendar = Calendar.getInstance();
  calendar.setTime(date);

  calendar.add(Calendar.DATE, dd);

  String mm = String.valueOf(calendar.get(Calendar.MONTH) + 1);
  if (mm.length() == 1) {
    mm = "0" + mm;
  }
  String day = String.valueOf(calendar.get(Calendar.DATE));
  if (day.length() == 1) {
    day = "0" + day;

  }
  String returnDate = String.valueOf(calendar.get(Calendar.YEAR)) + "-" + mm
      + "-" + day;

  return returnDate;

}

//一个日期上加dd个工作日
public static String DateAddWorkday(String startDate, int dd) {
  java.text.DateFormat df = java.text.DateFormat.getDateInstance();
  java.util.Date date = new java.util.Date();
  try {
    date = df.parse(startDate);
  }
  catch (Exception ex) {
    System.out.print(ex);
  }

  Calendar calendar = Calendar.getInstance();
  calendar.setTime(date);

  while (dd > 0) {
    //Calendar.DAY_OF_WEEK返回的 1 是星期天
    if ( (calendar.get(Calendar.DAY_OF_WEEK) == 1) ||
        (calendar.get(Calendar.DAY_OF_WEEK) == 7)) {
      calendar.add(Calendar.DATE, 1);
    }
    else {
      calendar.add(Calendar.DATE, 1);
      dd = -1;
    }
  }

  String mm = String.valueOf(calendar.get(Calendar.MONTH) + 1);
  String day = String.valueOf(calendar.get(Calendar.DATE));

  if (mm.length() == 1) {
    mm = "0" + mm;
  }
  if (day.length() == 1) {
    day = "0" + day;

  }
  String returnDate = String.valueOf(calendar.get(Calendar.YEAR)) + "-" +
      mm + "-" + day;

  return returnDate;

}

//返回当前日期,类型为格式"yyyy-mm-dd"的字符串
public static String getDate() {
  java.text.SimpleDateFormat d = new java.text.SimpleDateFormat();
  d.applyPattern("yyyy-MM-dd");
  java.util.Date nowdate = new java.util.Date();
  String str_date = d.format(nowdate);
  return str_date;
}

public static String DateToStr(java.util.Date date) {
  java.text.SimpleDateFormat d = new java.text.SimpleDateFormat();
  d.applyPattern("yyyy-MM-dd");
  String str_date = d.format(date);
  return str_date;
}

//返回指定年月的天数
public static int getMonthDayNum(int year, int month) {
  if (month == 2) {
    return year % 400 != 0 && (year % 4 != 0 || year % 100 == 0) ? 28 : 29;
  }
  String SmallMonth = ",4,6,9,11,";
  return SmallMonth.indexOf(String.valueOf(String.valueOf( (new StringBuffer(
      ",")).append(String.valueOf(month)).append(",")))) < 0 ? 31 : 30;
}

//返回当前时间
public static String getTime() {
  java.util.Date date = new java.util.Date();
  java.sql.Time time;
  time = new Time(date.getTime());
  String strTime = time.toString();
  return strTime;
}

public static int getYearMonthDate(String strDate, String style) {
  int year;
  int month;
  int day;
  int firstDash;
  int secondDash;
  if (strDate == null) {
    return 0;
  }
  firstDash = strDate.indexOf('-');
  secondDash = strDate.indexOf('-', firstDash + 1);
  if ( (firstDash > 0) & (secondDash > 0) &
      (secondDash < strDate.length() - 1)) {
    year = Integer.parseInt(strDate.substring(0, firstDash));
    month = Integer.parseInt(strDate.substring(firstDash + 1, secondDash));
    day = Integer.parseInt(strDate.substring(secondDash + 1));
  }
  else {
    return 0;
  }
  if (style.equalsIgnoreCase("Y")) {
    return year;
  }
  else if (style.equalsIgnoreCase("M")) {
    return month;
  }
  else if (style.equalsIgnoreCase("D")) {
    return day;
  }
  else {
    return 0;
  }
}

public static int getCurrentHour() {
  SimpleDateFormat f = new SimpleDateFormat("HH");
  String hh = f.format(new Timestamp(System.currentTimeMillis()));
  return Integer.parseInt(hh);
}

//返回两日期差的天数
public static int DateDiff(java.sql.Date date1, java.sql.Date date2) {
  int i = (int) ( (date1.getTime() - date2.getTime()) / 3600 / 24 / 1000);
  return i;
}

public static java.sql.Timestamp getTimestamp() {
  try {
    java.text.SimpleDateFormat myFormat = new SimpleDateFormat(
        "yyyy-MM-dd HH:mm:ss");
    java.util.Calendar calendar = java.util.Calendar.getInstance();
    String mystrdate = myFormat.format(calendar.getTime());
    return java.sql.Timestamp.valueOf(mystrdate);
  }
  catch (Exception e) {
    return null;
  }
}

/*****************songwhung***************/
public static String getTimeString() {
  try {
    java.text.SimpleDateFormat myFormat = new SimpleDateFormat(
        "yyyy-MM-dd HH:mm:ss");
    java.util.Calendar calendar = java.util.Calendar.getInstance();
    String mystrdate = myFormat.format(calendar.getTime());
    return mystrdate;
  }
  catch (Exception e) {
    return null;
  }
}

/*****************songwhung***************/
public static String getCurrentHourMS() {
  SimpleDateFormat f = new SimpleDateFormat("HH:MM:SS");
  String hh = f.format(new Timestamp(System.currentTimeMillis()));
  return hh;
}

public static java.sql.Timestamp getTimestamp(String datestr) {
  try {
    java.text.SimpleDateFormat myFormat = new SimpleDateFormat(
        "yyyy-MM-dd HH:mm:ss");
    String mystrdate = myFormat.format(myFormat.parse(datestr));
    return java.sql.Timestamp.valueOf(mystrdate);
  }
  catch (Exception e) {
    return null;
  }
}

public static java.sql.Timestamp getDate(String datestr) {
  datestr = datestr + " 00:00:00";
  try {
    java.text.SimpleDateFormat myFormat = new SimpleDateFormat(
        "yyyy-MM-dd HH:mm:ss");
    java.util.Date date = myFormat.parse(datestr);
    String mystrdate = myFormat.format(date);
    return java.sql.Timestamp.valueOf(mystrdate);
  }
  catch (Exception e) {
    return null;
  }
}

public static java.util.Date StrToDate(String strDate) {
  int year;
  int month;
  int day;
  int firstDash;
  int secondDash;
  if (strDate == null) {
    return null;
  }
  firstDash = strDate.indexOf('-');
  secondDash = strDate.indexOf('-', firstDash + 1);
  if ( (firstDash > 0) & (secondDash > 0) &
      (secondDash < strDate.length() - 1)) {
    year = Integer.parseInt(strDate.substring(0, firstDash));
    month = Integer.parseInt(strDate.substring(firstDash + 1, secondDash));
    day = Integer.parseInt(strDate.substring(secondDash + 1));
    Calendar c = java.util.Calendar.getInstance();
    c.set(year, month - 1, day);
    return c.getTime();
  }
  return null;
}

public static String getDate(java.sql.Date datestr) {

  try {
    java.text.SimpleDateFormat myFormat = new SimpleDateFormat(
        "MM/dd/yyyy");
    String mystrdate = myFormat.format(datestr);

    return mystrdate;
  }
  catch (Exception e) {
    e.printStackTrace();
    return null;
  }
}

/********四舍五入************/
public static float mathRound(float num, int n) {
  float realValue = 0;
  int dd = 1;
  double tempnum = 0;
  for (int i = 0; i < n; i++) {
    dd *= 10;
  }
  tempnum = num * dd;
  tempnum = Math.round(tempnum);
  realValue = (float) tempnum / dd;
  return realValue;
}

public static String getTimeStamp() {
  SimpleDateFormat format = new SimpleDateFormat("yyMMddHHmmss");
  return format.format(new Timestamp(System.currentTimeMillis()));
}
/**
 * 
 * @param style
 * @return
 */
public static String getCurrentTime(String style) {
	  SimpleDateFormat format = new SimpleDateFormat(style);
	  return format.format(new Timestamp(System.currentTimeMillis()));
}

public static void main(String[] argv) {
  DateUtil date = new DateUtil();
  System.out.println( (new java.util.Date()));
  System.out.println(date.getSqlDate(new java.util.Date()));
  System.out.println(date.getDate());
  System.out.println(date.getTime());
  System.out.println(date.DateAdd("2004-10-10", 2));
  System.out.println(date.getTimestamp().toString());
  String date2 = date.getTimestamp().toString();
  System.out.println(date.StrToDate("2006-02-07"));
  

}

}