java时间处理工具类总结二

package org.util.date;

import java.text.ParseException;
import java.text.SimpleDateFormat;
import org.apache.commons.logging.LogFactory;
import java.util.GregorianCalendar;
import org.apache.commons.logging.Log;
import java.util.Date;
import java.util.Calendar;

/**
* <p>Title: </p>
*
* <p>Description: </p>
*
* <p>Copyright: Copyright (c) 2007</p>
*
* <p>Company: </p>
*
* @author not attributable
* @version 1.0
*/
public class DateUtil
{
private static Log log = LogFactory.getLog(DateUtil.class);

private static String datePattern = "yyyy-MM-dd";

private static String timePattern = "HH:mm";

/**
* Return 缺省的日期格式 (yyyy/MM/dd)
*
* @return 在页面中显示的日期格式
*/
public static String getDatePattern()
{
return datePattern;
}
/**
* 根据日期格式，返回日期按datePattern格式转换后的字符串
*
* @param aDate
*            日期对象
* @return 格式化后的日期的页面显示字符串
*/
public static final String getDate(Date aDate)
{
SimpleDateFormat df = null;
String returnValue = "";
if (aDate != null)
{
df = new SimpleDateFormat(datePattern);
returnValue = df.format(aDate);
}
return (returnValue);
}
public static final String getDate(String pattern)
{
Date date = new Date();
return getDate(date, pattern);
}
public static final String getDate(Date date, String pattern)
{
SimpleDateFormat df = null;
String returnValue = "";
if (date != null)
{
df = new SimpleDateFormat(pattern);
returnValue = df.format(date);
}
return (returnValue);
}
public static Date getDate(String dateString, String pattern)
{
SimpleDateFormat df = null;
Date date = new Date();
if (dateString != null)
{
try
{
df = new SimpleDateFormat(pattern);
date = df.parse(dateString);
}
catch(Exception e)
{}
}
return date;
}
/**
* 按照日期格式，将字符串解析为日期对象
*
* @param aMask
*            输入字符串的格式
* @param strDate
*            一个按aMask格式排列的日期的字符串描述
* @return Date 对象
* @see java.text.SimpleDateFormat
* @throws ParseException
*/
public static final Date convertStringToDate(String aMask, String strDate)
{
SimpleDateFormat df = null;
Date date = null;
df = new SimpleDateFormat(aMask);
if (log.isDebugEnabled())
{
log.debug("converting '" + strDate + "' to date with mask '" + aMask + "'");
}
try
{
date = df.parse(strDate);
}
catch (ParseException pe)
{}
return (date);
}

/**
* This method returns the current date time in the format: yyyy/MM/dd HH:MM
* a
*
* @param theTime
*            the current time
* @return the current date/time
*/
public static String getTimeNow(Date theTime)
{
return getDateTime(timePattern, theTime);
}

/**
* This method returns the current date in the format: yyyy/MM/dd
*
* @return the current date
* @throws ParseException
*/
public static Calendar getToday() throws ParseException
{
Date today = new Date();
SimpleDateFormat df = new SimpleDateFormat(datePattern);
// This seems like quite a hack (date -> string -> date),
// but it works ;-)
String todayAsString = df.format(today);
Calendar cal = new GregorianCalendar();
cal.setTime(convertStringToDate(todayAsString));
return cal;
}
/**
* This method generates a string representation of a date's date/time in
* the format you specify on input
*
* @param aMask
*            the date pattern the string is in
* @param aDate
*            a date object
* @return a formatted string representation of the date
*
* @see java.text.SimpleDateFormat
*/
public static final String getDateTime(String aMask, Date aDate)
{
SimpleDateFormat df = null;
String returnValue = "";
if (aDate == null)
{
log.error("aDate is null!");
}
else
{
df = new SimpleDateFormat(aMask);
returnValue = df.format(aDate);
}
return (returnValue);
}
/**
* 根据日期格式，返回日期按datePattern格式转换后的字符串
* @param aDate Date
* @return String
*/
public static final String convertDateToString(Date aDate)
{
return getDateTime(datePattern, aDate);
}
/**
* 按照日期格式，将字符串解析为日期对象
* @param strDate String
* @return Date
* @throws ParseException
*/
public static Date convertStringToDate(String strDate)
{
Date aDate = null;
if (log.isDebugEnabled())
{
log.debug("converting date with pattern: " + datePattern);
}
aDate = convertStringToDate(datePattern, strDate);
return aDate;
}

public static String getYear()
{
Date date = new Date();
return getDate(date, "yyyy");
}
public static String getMonth()
{
Date date = new Date();
return getDate(date, "MM");
}
public static String getDay()
{
Date date = new Date();
return getDate(date, "dd");
}
/**
* 返回小时
*
* @param date
* 日期
* @return 返回小时
*/
public static int getHour(java.util.Date date)
{
java.util.Calendar c = java.util.Calendar.getInstance();
c.setTime(date);
return c.get(java.util.Calendar.HOUR_OF_DAY);
}
/**
* 返回分钟
*
* @param date
* 日期
* @return 返回分钟
*/
public static int getMinute(java.util.Date date)
{
java.util.Calendar c = java.util.Calendar.getInstance();
c.setTime(date);
return c.get(java.util.Calendar.MINUTE);
}
/**
* 返回秒钟
*
* @param date
* 日期
* @return 返回秒钟
*/
public static int getSecond(java.util.Date date)
{
java.util.Calendar c = java.util.Calendar.getInstance();
c.setTime(date);
return c.get(java.util.Calendar.SECOND);
}
/**
* 返回毫秒
*
* @param date
* 日期
* @return 返回毫秒
*/
public static long getMillis(java.util.Date date)
{
java.util.Calendar c = java.util.Calendar.getInstance();
c.setTime(date);
return c.getTimeInMillis();
}
/**
* 日期相加
*
* @param date
* 日期
* @param day
* 天数
* @return 返回相加后的日期
*/
public static java.util.Date addDate(java.util.Date date, int day)
{
java.util.Calendar c = java.util.Calendar.getInstance();
c.setTimeInMillis(getMillis(date) + ((long) day) * 24 * 3600 * 1000);
return c.getTime();
}
/**
* 日期相减
*
* @param date
* 日期
* @param date1
* 日期
* @return 返回相减后的日期
*/
public static int diffDate(java.util.Date date, java.util.Date date1)
{
return (int) ((getMillis(date) - getMillis(date1)) / (24 * 3600 * 1000));
}
public static int diffDateToHour(Date date, Date date1)
{
return (int) ((getMillis(date) - getMillis(date1)) / (1000 * 60* 60));
}
}