例如,我有日期:“23/2/2010”(2010年2月23日)。我想把它传递给一个返回星期几的函数。我该怎么做呢?
在这个例子中,函数应该返回String "Tue"。
此外,如果只需要日期顺序,如何检索?
例如,我有日期:“23/2/2010”(2010年2月23日)。我想把它传递给一个返回星期几的函数。我该怎么做呢?
在这个例子中,函数应该返回String "Tue"。
此外,如果只需要日期顺序,如何检索?
当前回答
这是正确的…
java.time.LocalDate; //package related to time and date
它提供了内置方法getDayOfWeek()来获取特定星期的日期:
int t;
Scanner s = new Scanner(System.in);
t = s.nextInt();
s.nextLine();
while(t-->0) {
int d, m, y;
String ss = s.nextLine();
String []sss = ss.split(" ");
d=Integer.parseInt(sss[0]);
m = Integer.parseInt(sss[1]);
y = Integer.parseInt(sss[2]);
LocalDate l = LocalDate.of(y, m, d); //method to get the localdate instance
System.out.println(l.getDayOfWeek()); //this returns the enum DayOfWeek
要将枚举l.getDayOfWeek()的值赋给一个字符串,您可能会使用enum中名为name()的方法,该方法返回enum对象的值。
其他回答
我用这个
String[] weekdays = "Sunday Monday Tuesday Wednesday Thursday Friday Saturday".split(" ");
然后
weekdays[calendar.get(Calendar.DAY_OF_WEEK) - 1]
获取特定的工作日
对于Java 8或更高版本,Localdate更可取
import java.time.LocalDate;
public static String findDay(int month, int day, int year) {
LocalDate localDate = LocalDate.of(year, month, day);
java.time.DayOfWeek dayOfWeek = localDate.getDayOfWeek();
System.out.println(dayOfWeek);
return dayOfWeek.toString();
}
注意:如果输入是字符串/用户定义的,那么你应该把它解析成int。
通过使用java.util.scanner包给用户输入日期、月和年来查找星期几的程序:
import java.util.Scanner;
public class Calender {
public static String getDay(String day, String month, String year) {
int ym, yp, d, ay, a = 0;
int by = 20;
int[] y = new int[]{6, 4, 2, 0};
int[] m = new int []{0, 3, 3, 6, 1, 4, 6, 2, 5, 0, 3, 5};
String[] wd = {"Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"};
int gd = Integer.parseInt(day);
int gm = Integer.parseInt(month);
int gy = Integer.parseInt(year);
ym = gy % 100;
yp = ym / 4;
ay = gy / 100;
while (ay != by) {
by = by + 1;
a = a + 1;
if(a == 4) {
a = 0;
}
}
if ((ym % 4 == 0) && (gm == 2)) {
d = (gd + m[gm - 1] + ym + yp + y[a] - 1) % 7;
} else
d = (gd + m[gm - 1] + ym + yp + y[a]) % 7;
return wd[d];
}
public static void main(String[] args) {
Scanner in = new Scanner(System.in);
String day = in.next();
String month = in.next();
String year = in.next();
System.out.println(getDay(day, month, year));
}
}
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());
public class TryDateFormats {
public static void main(String[] args) throws ParseException {
String month = "08";
String day = "05";
String year = "2015";
String inputDateStr = String.format("%s/%s/%s", day, month, year);
Date inputDate = new SimpleDateFormat("dd/MM/yyyy").parse(inputDateStr);
Calendar calendar = Calendar.getInstance();
calendar.setTime(inputDate);
String dayOfWeek = calendar.getDisplayName(Calendar.DAY_OF_WEEK, Calendar.LONG, Locale.US).toUpperCase();
System.out.println(dayOfWeek);
}
}