获取某年第几周的起始终止日期

Question

本帖最后由 shf156184620 于 2009-12-19 10:12:45 编辑

Answer 1

public static void main(String[] args) {
System.out.println(getDateByWeek(2009,1,"start"));
}

public static String getDateByWeek(int year, int week,String type){
int offset = 0;
if("end".equals(type))  offset=6;
Calendar c= Calendar.getInstance();
c.set(Calendar.YEAR, year);
c.set(Calendar.WEEK_OF_YEAR, week);
c.add(Calendar.DAY_OF_YEAR, offset);
return c.get(Calendar.YEAR)+"-"+(c.get(Calendar.MONTH)+1)+"-"+c.get(Calendar.DAY_OF_MONTH);
}

Answer 2

import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.GregorianCalendar;public class DateTest { /**
 * @param args
 */
static Calendar cal=new GregorianCalendar();
public static String getStartDateByWeek(int year, int week){
cal.set(Calendar.YEAR, year);
cal.set(Calendar.WEEK_OF_YEAR, week);
cal.set(Calendar.DAY_OF_WEEK, 1);
Date result=cal.getTime();
if(result.getTime()<new GregorianCalendar(2009,0,1).getTimeInMillis())
return new SimpleDateFormat("yyyy-MM-dd").format(new GregorianCalendar(2009,0,1).getTime());
return new SimpleDateFormat("yyyy-MM-dd").format(result);
}

public static String getEndDateByWeek(int year, int week){
cal.set(Calendar.YEAR, year);
cal.set(Calendar.WEEK_OF_YEAR, week);
cal.set(Calendar.DAY_OF_WEEK, 7);
Date result=cal.getTime();
if(result.getTime()>new GregorianCalendar(2009,12,31).getTimeInMillis())
return new SimpleDateFormat("yyyy-MM-dd").format(new GregorianCalendar(2009,11,31).getTime());
return new SimpleDateFormat("yyyy-MM-dd").format(result);
}
public static void main(String[] args) {
// TODO Auto-generated method stub
System.out.println(getStartDateByWeek(2009,1));
System.out.println(getEndDateByWeek(2009,1));
}}
结果：2009-01-01
2009-01-03多查一下API，多测试几次就可以了

Answer 3

}
public String getStartDateByWeek(int year, int week){
Calendar c=Calendar.getInstance();
c.set(Calendar.YEAR,year);
c.set(Calendar.WEEK_OF_YEAR,week);
SimpleDateFormat s=new SimpleDateFormat("yyyy-MM-dd");

    String starTime=s.format(c.getTime());
    return starTime;

}
public String getEndDateByWeek(int year, int week){
Calendar c=Calendar.getInstance();
c.set(Calendar.YEAR,year);
c.set(Calendar.WEEK_OF_YEAR,week);
SimpleDateFormat s=new SimpleDateFormat("yyyy-MM-dd");
c.add(Calendar.DAY_OF_MONTH,6);

    String endTime=s.format(c.getTime());
    return endTime;
}
新年刚开始那天所在星期的周六为新年第一周的开始时间，以后一次加7为第几周的开始时间，不知道这个会不会影响到你的应用