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
private String getDay(Date date){
SimpleDateFormat simpleDateFormat = new SimpleDateFormat("EEEE");
//System.out.println("DAY "+simpleDateFormat.format(date).toUpperCase());
return simpleDateFormat.format(date).toUpperCase();
}
private String getDay(String dateStr){
//dateStr must be in DD-MM-YYYY Formate
Date date = null;
String day=null;
try {
date = new SimpleDateFormat("DD-MM-YYYY").parse(dateStr);
SimpleDateFormat simpleDateFormat = new SimpleDateFormat("EEEE");
//System.out.println("DAY "+simpleDateFormat.format(date).toUpperCase());
day = simpleDateFormat.format(date).toUpperCase();
} catch (ParseException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return day;
}
其他回答
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;
}
LocalDate date=LocalDate.now();
System.out.println(date.getDayOfWeek());//prints THURSDAY
System.out.println(date.getDayOfWeek().getDisplayName(TextStyle.SHORT, Locale.US) ); //prints Thu
java.time.DayOfWeek is a enum which returns the singleton instance for the day-of-week of the weekday of the date.
可以使用以下代码片段进行输入,如(day = "08", month = "05", year = "2015",输出将是"WEDNESDAY")
Calendar calendar = Calendar.getInstance();
calendar.set(Calendar.DAY_OF_MONTH, Integer.parseInt(day));
calendar.set(Calendar.MONTH, (Integer.parseInt(month)-1));
calendar.set(Calendar.YEAR, Integer.parseInt(year));
String dayOfWeek = calendar.getDisplayName(Calendar.DAY_OF_WEEK, Calendar.LONG, Locale.US).toUpperCase();
一句话回答:
return LocalDate.parse("06/02/2018",DateTimeFormatter.ofPattern("dd/MM/yyyy")).getDayOfWeek().name();
使用的例子:
public static String getDayOfWeek(String date){
return LocalDate.parse(date, DateTimeFormatter.ofPattern("dd/MM/yyyy")).getDayOfWeek().name();
}
public static void callerMethod(){
System.out.println(getDayOfWeek("06/02/2018")); //TUESDAY
}
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