Beispiele für Java-Datums- und Kalenderdaten
Dieses Tutorial zeigt Ihnen, wie Sie mitjava.util.Date
undjava.util.Calendar
arbeiten.
1. Java-Datumsbeispiele
Einige Beispiele für die Arbeit mitDate
APIs.
Example 1.1 - Datum in Zeichenfolge konvertieren.
SimpleDateFormat sdf = new SimpleDateFormat("dd/M/yyyy"); String date = sdf.format(new Date()); System.out.println(date); //15/10/2013
Example 1.2 - String in Datum konvertieren.
SimpleDateFormat sdf = new SimpleDateFormat("dd-M-yyyy hh:mm:ss"); String dateInString = "31-08-1982 10:20:56"; Date date = sdf.parse(dateInString); System.out.println(date); //Tue Aug 31 10:20:56 SGT 1982
P.S Refer to this – SimpleDateFormat JavaDoc for detail date and time patterns.
Example 1.3 - Aktuelle Datums- und Uhrzeitangabe abrufen
SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss"); Date date = new Date(); System.out.println(dateFormat.format(date)); //2013/10/15 16:16:39
Example 1.4 - Kalender in Datum konvertieren
Calendar calendar = Calendar.getInstance(); Date date = calendar.getTime();
2. Beispiele für Java-Kalender
Einige Beispiele für die Arbeit mitCalendar
APIs.
Example 2.1 - Aktuelle Datums- und Uhrzeitangabe abrufen
SimpleDateFormat sdf = new SimpleDateFormat("yyyy MMM dd HH:mm:ss"); Calendar calendar = new GregorianCalendar(2013,0,31); System.out.println(sdf.format(calendar.getTime()));
Ausgabe
2013 Jan 31 00:00:00
Example 2.2 - Einfaches Kalenderbeispiel
SimpleDateFormat sdf = new SimpleDateFormat("yyyy MMM dd HH:mm:ss"); Calendar calendar = new GregorianCalendar(2013,1,28,13,24,56); int year = calendar.get(Calendar.YEAR); int month = calendar.get(Calendar.MONTH); // Jan = 0, dec = 11 int dayOfMonth = calendar.get(Calendar.DAY_OF_MONTH); int dayOfWeek = calendar.get(Calendar.DAY_OF_WEEK); int weekOfYear = calendar.get(Calendar.WEEK_OF_YEAR); int weekOfMonth= calendar.get(Calendar.WEEK_OF_MONTH); int hour = calendar.get(Calendar.HOUR); // 12 hour clock int hourOfDay = calendar.get(Calendar.HOUR_OF_DAY); // 24 hour clock int minute = calendar.get(Calendar.MINUTE); int second = calendar.get(Calendar.SECOND); int millisecond= calendar.get(Calendar.MILLISECOND); System.out.println(sdf.format(calendar.getTime())); System.out.println("year \t\t: " + year); System.out.println("month \t\t: " + month); System.out.println("dayOfMonth \t: " + dayOfMonth); System.out.println("dayOfWeek \t: " + dayOfWeek); System.out.println("weekOfYear \t: " + weekOfYear); System.out.println("weekOfMonth \t: " + weekOfMonth); System.out.println("hour \t\t: " + hour); System.out.println("hourOfDay \t: " + hourOfDay); System.out.println("minute \t\t: " + minute); System.out.println("second \t\t: " + second); System.out.println("millisecond \t: " + millisecond);
Ausgabe
2013 Feb 28 13:24:56 year : 2013 month : 1 dayOfMonth : 28 dayOfWeek : 5 weekOfYear : 9 weekOfMonth : 5 hour : 1 hourOfDay : 13 minute : 24 second : 56 millisecond : 0
Example 2.3 - Stellen Sie ein Datum manuell ein.
SimpleDateFormat sdf = new SimpleDateFormat("yyyy MMM dd HH:mm:ss"); Calendar calendar = new GregorianCalendar(2013,1,28,13,24,56); System.out.println("#1. " + sdf.format(calendar.getTime())); //update a date calendar.set(Calendar.YEAR, 2014); calendar.set(Calendar.MONTH, 11); calendar.set(Calendar.MINUTE, 33); System.out.println("#2. " + sdf.format(calendar.getTime()));
Ausgabe
#1. 2013 Feb 28 13:24:56 #2. 2014 Dec 28 13:33:56
Example 2.4– Addiere oder subtrahiere von einem Datum.
SimpleDateFormat sdf = new SimpleDateFormat("yyyy MMM dd"); Calendar calendar = new GregorianCalendar(2013,10,28); System.out.println("Date : " + sdf.format(calendar.getTime())); //add one month calendar.add(Calendar.MONTH, 1); System.out.println("Date : " + sdf.format(calendar.getTime())); //subtract 10 days calendar.add(Calendar.DAY_OF_MONTH, -10); System.out.println("Date : " + sdf.format(calendar.getTime()));
Ausgabe
Date : 2013 Nov 28 Date : 2013 Dec 28 Date : 2013 Dec 18
Example 2.5– Datum in Kalender konvertieren.
SimpleDateFormat sdf = new SimpleDateFormat("dd-M-yyyy hh:mm:ss"); String dateInString = "22-01-2015 10:20:56"; Date date = sdf.parse(dateInString); Calendar calendar = Calendar.getInstance(); calendar.setTime(date);