从用户输入中获取星期几

Question

Date date= (new GregorianCalendar(year, month, day)).getTime();
SimpleDateFormat f = new SimpleDateFormat("EEEE");
String dow=f.format(date);

System.out.print("This date is a "+dow);

I have the user input a month(1-12) a day(1-31) and a year(1600-2400) It works fine only it displays the wrong day. For example it says that Jan 1st 2014 is a Saturday but it was a Wednesday. It is probably because I didn't factor in leap years but I don't have a clue to go about doing that. Neither do I know how to tell it how many days in each month. An array? Hopefully minimal lines as well.

Thanks so much!!! This has been bugging me for an hour +. And something so simple, I should have figured. I must be tired.

Thanks!!!!!!!

Answer 1

Month is Zero based. Try,

Date date= (new GregorianCalendar(year, month-1, day)).getTime();
    SimpleDateFormat f = new SimpleDateFormat("EEEE");
    String dow=f.format(date);

Answer 2

The answer by Shashank Kadne is correct.

Joda-Time

FYI, this work is simpler and cleaner using the Joda-Time 2.3 library.

Joda-Time uses sensible one-based counting for things such as:

• Month-of-Year
  January = 1, February = 2, and so on.
• Day-of-Week
  Monday = 1, Sunday = 7. (Standard ISO 8601 week)

Joda-Time DateTime objects know their own time zone, unlike java.util.Date objects.

Joda-Time leverages a specified Locale object to render localized strings.

Example Code

// Specify a time zone rather than rely on default.
DateTimeZone timeZone = DateTimeZone.forID( "Europe/Paris" );

int year = 2014;
int month = 1; // Sensible one-based counting. January = 1, February = 2, …
int dayOfMonth = 2;

DateTime dateTime = new DateTime( year, month, dayOfMonth, 0, 0, 0, timeZone );

// Day-of-week info.
int dayOfWeekNumber = dateTime.getDayOfWeek(); // Standard week (ISO 8601). Monday = 1, Sunday = 7.
DateTime.Property dayOfWeekProperty = dateTime.dayOfWeek();
String dayOfWeekName_Short = dayOfWeekProperty.getAsShortText( Locale.FRANCE );
String dayOfWeekName_Long = dayOfWeekProperty.getAsText( Locale.FRANCE );

Dump to console…

System.out.println( "dateTime: " + dateTime );
System.out.println( "dayOfWeekNumber: " + dayOfWeekNumber );
System.out.println( "dayOfWeekName_Short: " + dayOfWeekName_Short );
System.out.println( "dayOfWeekName_Long: " + dayOfWeekName_Long );

When run…

dateTime: 2014-01-02T00:00:00.000+01:00
dayOfWeekNumber: 4
dayOfWeekName_Short: jeu.
dayOfWeekName_Long: jeudi

Without Time & Time Zone

If you truly want only date without any time or time zone, then write similar code but with the LocalDate class.