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;
       }