DateTimeUtil 获取 当天是星期几

package com.powerpeak.util;

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

public class DateTimeUtil {

   public static Date String2DateTime(String date) {
      Date dt = null;
      SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
      try {
         dt = sdf.parse(date);
      } catch (ParseException e) {
         e.printStackTrace();
      }
      return dt;
   }
   
   public static Date String2Date(String date) {
      Date dt = null;
      SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
      try {
         dt = sdf.parse(date);
      } catch (ParseException e) {
         e.printStackTrace();
      }
      return dt;
   }
   
   public static Date DateAddMinute(Date date, int minute) {
      Date dt = null;
        Calendar c = Calendar.getInstance();
        c.setTime(date);
        c.add(Calendar.MINUTE, minute);
        dt = c.getTime();
      return dt;
   }
   
   public static Date DateAddHour(Date date, int hour) {
      Date dt = null;
        Calendar c = Calendar.getInstance();
        c.setTime(date);
        c.add(Calendar.HOUR, hour);
        dt = c.getTime();
      return dt;
   }
   
   public static Date DateAddDay(Date date, int day) {
      Date dt = null;
        Calendar c = Calendar.getInstance();
        c.setTime(date);
        c.add(Calendar.DATE, day);
        dt = c.getTime();
      return dt;
   }
   
   public static Date DateAddMonth(Date date, int month) {
      Date dt = null;
        Calendar c = Calendar.getInstance();
        c.setTime(date);
        c.add(Calendar.MONTH, month);
        dt = c.getTime();
      return dt;
   }
   
   public static Date DateAddYear(Date date, int year) {
      Date dt = null;
        Calendar c = Calendar.getInstance();
        c.setTime(date);
        c.add(Calendar.YEAR, year);
        dt = c.getTime();
      return dt;
   }

   public static int DateDayOfMinute(Date date) {
      int num = 0;
      
      Calendar c = Calendar.getInstance();
        c.setTime(date);
        
        num = c.get(Calendar.HOUR_OF_DAY)*60;
        num = num + c.get(Calendar.MINUTE);

      return num;
   }

   public static String DateTime2String(Date date) {
      String str = null;
      SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
      str = sdf.format(date);
      return str;
   }

   public static String Date2String(Date date) {
      String str = null;
      SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
      str = sdf.format(date);
      return str;
   }
   // 获取星期天
   public static int getWeekOfDay(Date date) {
      int week = 0;
      
      Calendar c = Calendar.getInstance();
        c.setTime(date);

        week = c.get(Calendar.DAY_OF_WEEK) - 1;

      return week;
   }
}