java写的日期工具，根据设置日期获取指定的一周或者一个月的所有日期
程序员文章站
2022-07-13 13:59:40
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在做项目中遇到一个关于日记的问题，国外算一周是从周末到周六，而国内一周是从周一到周天。很多软件需要获取一个月或者一周的所有日期来进行数据统计，为了方便大家开发，避免重复劳动。特地写了一个DateTools工具类，使用方法都在main函数里。
import java.text.Format;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.Date;
import java.util.List;
public class DateTools {
public static void main(String[] args) {
System.out.println("--------------当前日期下一周的每一天--------------");
List<String> lst= getALlweekDays();//获取当前日期下，一周的每一天
for(String s:lst)
{
System.out.println(s);
}
List <String>lst2=getAllDaysMonth();//获取当前日期下，一个月的每一天
System.out.println("--------------一个月的每一天--------------");
for(String s2:lst2)
{
System.out.println(s2);
}
System.out.println("--------------根据特定的日期‘2014-8-1’获取特定日期所在一周的每一天--------------");
Date d=DateTools.paraseStringToDate("2014-8-1");
List <String>lst3=DateTools.getAllweekDays(d);
for(String s3:lst3)
{
System.out.println(s3);
}
System.out.println("--------------根据特定的日期‘2014-8-1’获取特定日期所在一个月的每一天--------------");
Date d2=DateTools.paraseStringToDate("2014-8-1");
List <String>lst4=DateTools.getAllDaysMonthByDate(d2);
for(String s3:lst4)
{
System.out.println(s3);
}
}
private static final int FIRST_DAY = Calendar.MONDAY;
private static SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
public String getMonthStart()//获取月初日期
{
Date d = new Date();
// 月初
// System.out.println("月初" + sdf.format(getMonthStart(d)));
return sdf.format(getMonthStart(d));
}
public static String getMonthStartStr(Date d)//根据传入日期来获取一个月的开始时间
{
return sdf.format(getMonthStart(d));
}
public static String getMonthEndStr(Date d)//根据传入时间获取一个月月末时间
{
return sdf.format(getMonthEnd(d));
}
public static List<String>getAllDaysMonthByDate(Date d)//根据传入的日期获取所在月份所有日期
{
List<String> lst=new ArrayList();
Date date = getMonthStart(d);
Date monthEnd = getMonthEnd(d);
while (!date.after(monthEnd)) {
//System.out.println(sdf.format(date));
lst.add(sdf.format(date));
date = getNext(date);
}
return lst;
}
public static Date paraseStringToDate(String timestr )//将字符串转化为日期
{
Date date=null;
Format f = new SimpleDateFormat("yyyy-MM-dd");
try {
date = (Date) f.parseObject(timestr);
} catch (ParseException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return date;
}
public String getMonthEnd()//获取月末日期
{
Date d = new Date();
return sdf.format(getMonthEnd(d));
}
public static List<String>getAllDaysMonth()
{
List<String> lst=new ArrayList();
Date d = new Date();
// 月初
// System.out.println("月初" + sdf.format(getMonthStart(d)));
// 月末
//System.out.println("月末" + sdf.format(getMonthEnd(d)));
Date date = getMonthStart(d);
Date monthEnd = getMonthEnd(d);
while (!date.after(monthEnd)) {
//System.out.println(sdf.format(date));
lst.add(sdf.format(date));
date = getNext(date);
}
return lst;
}
private static Date getMonthStart(Date date) {
Calendar calendar = Calendar.getInstance();
calendar.setTime(date);
int index = calendar.get(Calendar.DAY_OF_MONTH);
calendar.add(Calendar.DATE, (1 - index));
return calendar.getTime();
}
private static Date getMonthEnd(Date date) {
Calendar calendar = Calendar.getInstance();
calendar.setTime(date);
calendar.add(Calendar.MONTH, 1);
int index = calendar.get(Calendar.DAY_OF_MONTH);
calendar.add(Calendar.DATE, (-index));
return calendar.getTime();
}
private static Date getNext(Date date) {
Calendar calendar = Calendar.getInstance();
calendar.setTime(date);
calendar.add(Calendar.DATE, 1);
return calendar.getTime();
}
public static String getWeekStartDay(Date d) {//根据日期来获取一周的第一天
Calendar c = Calendar.getInstance();
List <String>lst=new ArrayList();
c.setTime(d);
setToFirstDay(c);
for (int i = 0; i < 7; i++) {
String day = printDay(c);
lst.add(day);
c.add(Calendar.DATE, 1);
}
return lst.get(0);
}
public static String getWeekEndtDay(Date d) {//根据日期来获取一周的最后一天
Calendar c = Calendar.getInstance();
List <String>lst=new ArrayList();
c.setTime(d);
setToFirstDay(c);
for (int i = 0; i < 7; i++) {
String day = printDay(c);
lst.add(day);
c.add(Calendar.DATE, 1);
}
return lst.get(6);
}
public static List<String> getAllweekDays(Date d) {//根据日期来获取其所在周的每一天
Calendar c = Calendar.getInstance();
List <String>lst=new ArrayList();
c.setTime(d);
setToFirstDay(c);
for (int i = 0; i < 7; i++) {
String day = printDay(c);
lst.add(day);
c.add(Calendar.DATE, 1);
}
return lst;
}
public static List<String> getALlweekDays() {
List<String>lst=new ArrayList();
Calendar calendar = Calendar.getInstance();
setToFirstDay(calendar);
for (int i = 0; i < 7; i++) {
String day=printDay(calendar);
lst.add(day);
calendar.add(Calendar.DATE, 1);
}
return lst;
}
private static void setToFirstDay(Calendar calendar) {
while (calendar.get(Calendar.DAY_OF_WEEK) != FIRST_DAY) {
calendar.add(Calendar.DATE, -1);
}
}
private static String printDay(Calendar calendar) {
SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");
return dateFormat.format(calendar.getTime());
}
}