Date转换成星期几

import org.apache.commons.collections.CollectionUtils;
import org.springframework.stereotype.Component;
import org.springframework.util.StringUtils;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.*;
import java.util.stream.Collectors;

@Component
public class Date{
//指定的日期是星期几
   public static int getDayOfWeek(String date) {
       if(!StringUtils.isEmpty(date)){//判断传递的日期不为空
           SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd");	//限定格式为:年-月-日
           //抛出异常
		   try {
			   //类型转换
               Date parseDate = df.parse(date);
               Calendar c = Calendar.getInstance();
               c.setTime(parseDate);
			   //判断转换是否正确
               boolean isFirstSunday = (c.getFirstDayOfWeek() == Calendar.SUNDAY);
               //获取周几的数字
			   int weekDay = c.get(Calendar.DAY_OF_WEEK);
               if (isFirstSunday) {
                   weekDay = weekDay - 1;
                   if (weekDay == 0) {
                       weekDay = 7;
                   }
               }
			   //返回周几数字
               return weekDay;
           } catch (ParseException e) {
               e.printStackTrace();
           }
       }
       return 0;
   }
}