【转】本月的第一天和最后一天

 

1、Java日期循环

SimpleDateFormat formater = new SimpleDateFormat("yyyy-MM-dd");

String   dateStr1="2008-3-16"; 

String      dateStr2="2008-3-24"; 

java.util.Date dateBegin=formater.parse(dateStr1);

java.util.Date dateEnd=formater.parse(dateStr2);             



Calendar   ca=Calendar.getInstance(); 

while(dateBegin.compareTo(dateEnd)<=0){             

             ca.setTime(dateBegin);   

              ca.add(ca.DATE,1);//把dateBegin加上1天然后重新赋值给date1   

              dateBegin=ca.getTime();       

       }

2、Java获取当月的第一天和最后一天

Calendar cal = Calendar.getInstance(); 

SimpleDateFormat datef=new SimpleDateFormat("yyyy-MM-dd");
             //当前月的最后一天   
             cal.set( Calendar.DATE, 1 );
             cal.roll(Calendar.DATE, - 1 );
             Date endTime=cal.getTime();
             String endTime1=datef.format(endTime)+" 23:59:59";
              //当前月的第一天          
             cal.set(GregorianCalendar.DAY_OF_MONTH, 1); 
              Date beginTime=cal.getTime();
             String beginTime1=datef.format(beginTime)+" 00:00:00";


//循环输出日期
public static void main(String[] arg) throws Exception {
        GregorianCalendar g = new GregorianCalendar();
        g.setTime(new Date());
        int day = g.get(Calendar.DAY_OF_YEAR);
        int year = g.get(Calendar.YEAR);
        for (int i = 0; i < 400; i++) {
            SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
            String formatTime = sdf.format(g.getTime());
            System.out.println(formatTime);
            if(g.get(Calendar.YEAR) > year) {
                day = 0;
                year = g.get(Calendar.YEAR);
            }
            g.set(Calendar.DAY_OF_YEAR, day + 1);
            day++;
        }
    }