另一个“有趣”的方法是使用末日算法。这是一个更长的方法，但如果您不需要用给定的日期创建Calendar对象，那么它也更快。

import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.HashMap;
import java.util.Map;
import java.util.Random;

/**
 *
 * @author alain.janinmanificat
 */
public class Doomsday {

    public static HashMap<Integer, ArrayList<Integer>> anchorDaysMap = new HashMap<>();
    public static HashMap<Integer, Integer> doomsdayDate = new HashMap<>();
    public static String weekdays[] = new DateFormatSymbols(Locale.FRENCH).getWeekdays();

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) throws ParseException, ParseException {

        // Map is fed manually but we can use this to calculate it : http://en.wikipedia.org/wiki/Doomsday_rule#Finding_a_century.27s_anchor_day
        anchorDaysMap.put(Integer.valueOf(0), new ArrayList<Integer>() {
            {
                add(Integer.valueOf(1700));
                add(Integer.valueOf(2100));
                add(Integer.valueOf(2500));
            }
        });

        anchorDaysMap.put(Integer.valueOf(2), new ArrayList<Integer>() {
            {
                add(Integer.valueOf(1600));
                add(Integer.valueOf(2000));
                add(Integer.valueOf(2400));
            }
        });

        anchorDaysMap.put(Integer.valueOf(3), new ArrayList<Integer>() {
            {
                add(Integer.valueOf(1500));
                add(Integer.valueOf(1900));
                add(Integer.valueOf(2300));
            }
        });

        anchorDaysMap.put(Integer.valueOf(5), new ArrayList<Integer>() {
            {
                add(Integer.valueOf(1800));
                add(Integer.valueOf(2200));
                add(Integer.valueOf(2600));
            }
        });

        //Some reference date that always land on Doomsday
        doomsdayDate.put(Integer.valueOf(1), Integer.valueOf(3));
        doomsdayDate.put(Integer.valueOf(2), Integer.valueOf(14));
        doomsdayDate.put(Integer.valueOf(3), Integer.valueOf(14));
        doomsdayDate.put(Integer.valueOf(4), Integer.valueOf(4));
        doomsdayDate.put(Integer.valueOf(5), Integer.valueOf(9));
        doomsdayDate.put(Integer.valueOf(6), Integer.valueOf(6));
        doomsdayDate.put(Integer.valueOf(7), Integer.valueOf(4));
        doomsdayDate.put(Integer.valueOf(8), Integer.valueOf(8));
        doomsdayDate.put(Integer.valueOf(9), Integer.valueOf(5));
        doomsdayDate.put(Integer.valueOf(10), Integer.valueOf(10));
        doomsdayDate.put(Integer.valueOf(11), Integer.valueOf(7));
        doomsdayDate.put(Integer.valueOf(12), Integer.valueOf(12));

        long time = System.currentTimeMillis();
        for (int i = 0; i < 100000; i++) {

            //Get a random date
            int year = 1583 + new Random().nextInt(500);
            int month = 1 + new Random().nextInt(12);
            int day = 1 + new Random().nextInt(7);

            //Get anchor day and DoomsDay for current date
            int twoDigitsYear = (year % 100);
            int century = year - twoDigitsYear;
            int adForCentury = getADCentury(century);
            int dd = ((int) twoDigitsYear / 12) + twoDigitsYear % 12 + (int) ((twoDigitsYear % 12) / 4);

            //Get the gap between current date and a reference DoomsDay date
            int referenceDay = doomsdayDate.get(month);
            int gap = (day - referenceDay) % 7;

            int result = (gap + adForCentury + dd) % 7;

            if(result<0){
                result*=-1;
            }
            String dayDate= weekdays[(result + 1) % 8];
            //System.out.println("day:" + dayDate);
        }
        System.out.println("time (ms) : " + (System.currentTimeMillis() - time)); //time (ms) : 80

         time = System.currentTimeMillis();
        for (int i = 0; i < 100000; i++) {
            Calendar c = Calendar.getInstance();
            //I should have used random date here too, but it's already slower this way
            c.setTime(new SimpleDateFormat("dd/MM/yyyy").parse("12/04/1861"));
//            System.out.println(new SimpleDateFormat("EE").format(c.getTime()));
            int result2 = c.get(Calendar.DAY_OF_WEEK);
//            System.out.println("day idx :"+ result2);
        }
        System.out.println("time (ms) : " + (System.currentTimeMillis() - time)); //time (ms) : 884
    }

    public static int getADCentury(int century) {
        for (Map.Entry<Integer, ArrayList<Integer>> entry : anchorDaysMap.entrySet()) {
            if (entry.getValue().contains(Integer.valueOf(century))) {
                return entry.getKey();
            }
        }
        return 0;
    }
}

是的。根据具体情况:

You can use java.util.Calendar: Calendar c = Calendar.getInstance(); c.setTime(yourDate); int dayOfWeek = c.get(Calendar.DAY_OF_WEEK); if you need the output to be Tue rather than 3 (Days of week are indexed starting at 1 for Sunday, see Calendar.SUNDAY), instead of going through a calendar, just reformat the string: new SimpleDateFormat("EE").format(date) (EE meaning "day of week, short version") if you have your input as string, rather than Date, you should use SimpleDateFormat to parse it: new SimpleDateFormat("dd/M/yyyy").parse(dateString) you can use joda-time's DateTime and call dateTime.dayOfWeek() and/or DateTimeFormat. edit: since Java 8 you can now use java.time package instead of joda-time

您可以尝试以下代码:

import java.time.*;

public class Test{
   public static void main(String[] args) {
      DayOfWeek dow = LocalDate.of(2010,Month.FEBRUARY,23).getDayOfWeek();
      String s = String.valueOf(dow);
      System.out.println(String.format("%.3s",s));
   }
}

  String inputDate = "01/08/2012";
  SimpleDateFormat format1 = new SimpleDateFormat("dd/MM/yyyy");
  Date dt1 = format1.parse(input_date);
  DateFormat format2 = new SimpleDateFormat("EEEE"); 
  String finalDay = format2.format(dt1);

使用此代码从输入日期中查找日期名称。简单且经过良好测试。

下面是两行代码片段，使用Java 1.8 Time API满足您的需求。

LocalDate localDate = LocalDate.of(Integer.valueOf(year),Integer.valueOf(month),Integer.valueOf(day));
String dayOfWeek = String.valueOf(localDate.getDayOfWeek());

你可以使用下面的方法通过传递一个特定的日期来获取星期几，

这里对于Calendar类的set方法，难点在于month参数的索引将从0开始。

public static String getDay(int day, int month, int year) {

        Calendar cal = Calendar.getInstance();

        if(month==1){
            cal.set(year,0,day);
        }else{
            cal.set(year,month-1,day);
        }

        int dow = cal.get(Calendar.DAY_OF_WEEK);

        switch (dow) {
        case 1:
            return "SUNDAY";
        case 2:
            return "MONDAY";
        case 3:
            return "TUESDAY";
        case 4:
            return "WEDNESDAY";
        case 5:
            return "THURSDAY";
        case 6:
            return "FRIDAY";
        case 7:
            return "SATURDAY";
        default:
            System.out.println("GO To Hell....");
        }

        return null;
    }