java 判断是否是周末

package   untitled7;
  import   java.util.Date;
  import   java.text.SimpleDateFormat;
  import   java.util.Calendar;
  import   java.text.DateFormat;
  public   class   test   {  

          public   static   void   main(String   args[]){
                  Date   date=   new   Date();
                  String   dateStr   =   "";
                  String   weekStr   =   "";
                  Calendar   calendar   =   Calendar.getInstance();
                  int   week   =   calendar.get(Calendar.DAY_OF_WEEK)-1;
                  switch(week){
                          case   0:
                                  weekStr   =   "星期日";
                                  break;
                          case   1:
                                  weekStr   =   "星期一";
                                  break;
                          case   2:
                                  weekStr   =   "星期二";
                                  break;
                          case   3:
                                  weekStr   =   "星期三";
                                  break;
                          case   4:
                                  weekStr   =   "星期四";
                                  break;
                          case   5:
                                  weekStr   =   "星期五";
                                  break;
                          case   6:
                                  weekStr   =   "星期六";
                                  break;
                  }
                  Date   dateBegin   =   new   Date();
                  Date   dateEnd   =   new   Date();
                  DateFormat   shortDateFormat   =   DateFormat.getDateInstance(0);
                  dateStr   =   shortDateFormat.format(date);
                  dateBegin.setTime(date.getTime()-(long)(week)*24*60*60*1000);
                  String   dateBeginStr   =   shortDateFormat.format(dateBegin);
                  dateEnd.setTime(date.getTime()+(long)(7-week-1)*24*60*60*1000);
                  String   dateEndStr   =   shortDateFormat.format(dateEnd);
                  System.out.println("今天是当年的第"+calendar.get(Calendar.WEEK_OF_YEAR   )+"周");
                  System.out.println("今天是当月的"+calendar.get(calendar.DAY_OF_WEEK_IN_MONTH)+"周");
                  System.out.println("今天是"+weekStr);
                  System.out.println("本周的开始时间是"+dateBeginStr);
                  System.out.println("本周的结束时间是"+dateEndStr);
                  calendar.set(   Calendar.DAY_OF_WEEK,   1   );
                  System.out.println(   "本周的开始时间是"+(calendar.get(Calendar.MONTH)+1)+"月"   +   calendar.get(   Calendar.DATE   )+"日");
                  calendar.set(Calendar.DAY_OF_WEEK,7);
                  System.out.println(   "本周的开始结束时间是"+(calendar.get(Calendar.MONTH)+1)+"月"   +   calendar.get(   Calendar.DATE   )+"日");
          }
  } 

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import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;

public class text {
        public static void main(String[] args) {
                final String dayNames[] = { "星期日", "星期一", "星期二", "星期三", "星期四",
                                "星期五", "星期六" };

                String s = "2006-01-1 16:30";
                SimpleDateFormat sdfInput = new SimpleDateFormat("yyyy-MM-dd HH:mm");

                Calendar calendar = Calendar.getInstance();
                Date date = new Date();

                try {
                        date = sdfInput.parse(s);
                } catch (ParseException e) {
                        e.printStackTrace();
                }

                calendar.setTime(date);
                int dayOfWeek = calendar.get(Calendar.DAY_OF_WEEK);

                System.out.println(dayNames[dayOfWeek - 1]);
        }
}  

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/*
*  判斷字串是否為有效的日期
*  日期格式20060101共8碼 (有效true，無效false)
*/
       public static boolean isDateValidate(String timeString){
              if(timeString==null || timeString.length()!=8){
                      return false;}
              try{
              java.text.SimpleDateFormat dFormat = new SimpleDateFormat("yyyyMMdd");
              dFormat.setLenient(false);
              java.util.Date d = dFormat.parse(timeString);
              java.util.Date ddd = dFormat.parse(timeString);
              }catch(Exception e){
                  return false;
              }

              return true;
       }