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@xiangzhuyuan
Created March 11, 2013 09:51
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about date
package com.demo;
import java.util.Calendar;
import java.util.Date;
public class DemoDateUtil {
//static DateUtil du = new DateUtil();
/**
* @param args
*/
@SuppressWarnings("deprecation")
public static void main(String[] args) {
Calendar cal=Calendar.getInstance();
Date date=cal.getTime();
Date du1=getStartOfLastWeek(date);
Date du2=getStartOfWeek(date);
Date du3=getStartOfMonth(date);
Date du4=getStartOfLastMonth(date);
Date du5=getStartOfNextMonth(date);
System.out.println(du1.toLocaleString());
System.out.println(du2.toLocaleString());
System.out.println(du3.toLocaleString());
System.out.println(du4.toLocaleString());
System.out.println(du5.toLocaleString());
/**
* 2013-3-4 17:49:44
* 2013-3-11 17:49:44
* 2013-3-1 17:49:44
* 2013-2-1 17:49:44
* 2013-4-1 17:49:44
*/
}
/**
* Start of the month
*
* @param inDate
* @return
*/
public static Date getStartOfMonth(Date inDate) {
if (inDate == null)
return null;
Calendar calendar = Calendar.getInstance();
calendar.setTime(inDate);
calendar.set(Calendar.DAY_OF_MONTH, 1);
return calendar.getTime();
}
/**
* Start of next month
*
* @param inDate
* @return
*/
public static Date getStartOfNextMonth(Date inDate) {
if (inDate == null)
return null;
Calendar calendar = Calendar.getInstance();
calendar.setTime(inDate);
calendar.add(Calendar.MONTH, 1);
calendar.set(Calendar.DAY_OF_MONTH, 1);
return calendar.getTime();
}
/**
* Start of last month
*
* @param inDate
* @return
*/
public static Date getStartOfLastMonth(Date inDate) {
if (inDate == null)
return null;
Calendar calendar = Calendar.getInstance();
calendar.setTime(inDate);
calendar.add(Calendar.MONTH, -1);
calendar.set(Calendar.DAY_OF_MONTH, 1);
return calendar.getTime();
}
/**
* Start of last week
*
* @param inDate
* @return
*/
public static Date getStartOfLastWeek(Date inDate) {
if (inDate == null)
return null;
Calendar calendar = Calendar.getInstance();
calendar.setTime(inDate);
if (calendar.get(Calendar.DAY_OF_WEEK) == Calendar.SUNDAY) {
calendar.add(Calendar.WEEK_OF_MONTH, -1);
}
calendar.add(Calendar.WEEK_OF_MONTH, -1);
calendar.set(Calendar.DAY_OF_WEEK, Calendar.MONDAY);
return calendar.getTime();
}
/**
* Start of the week
*
* @param inDate
* @return
*/
public static Date getStartOfWeek(Date inDate) {
if (inDate == null)
return null;
Calendar calendar = Calendar.getInstance();
calendar.setTime(inDate);
if (calendar.get(Calendar.DAY_OF_WEEK) == Calendar.SUNDAY) {
calendar.add(Calendar.WEEK_OF_MONTH, -1);
}
calendar.set(Calendar.DAY_OF_WEEK, Calendar.MONDAY);
return calendar.getTime();
}
}
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