Java adds and subtract dates from date class, year plus minus, month plus minus

Date D=new date ();
SimpleDateFormat df=new SimpleDateFormat ("Yyyy-mm-dd");
System.out.println ("Today's Date:" +df.format (d));
System.out.println ("Two days ago Date:" + Df.format (new Date (D.gettime ()-(LONG) 2 * 24 * 60 * 60 * 1000)));
System.out.println ("Date after three days:" + df.format (new Date (D.gettime () + (LONG) 3 * 24 * 60 * 60 * 1000)));

Java processing Date Time common methods:

1.java.util.calendar
The Calendar class is an abstract class that provides methods for converting between specific moments and a set of calendar fields such as year, MONTH, Day_of_month, HOUR, and provides methods for manipulating calendar fields, such as getting the date of the next week. The instantaneous value is expressed as a millisecond, which is the offset from the calendar element (that is, Greenwich Mean Time January 1, 1970, 00:00:00.000, Gregorian calendar).

Cases:

Java code

Calendar cal = Calendar.getinstance ();//Use the default time zone and locale to get a calendar.

Cal.add (Calendar.day_of_month,-1);//Take the day before the current date.

Cal.add (Calendar.day_of_month, + 1);//Take the day after the current date.

Format output Date by

Java.text.SimpleDateFormat format = new Java.text.SimpleDateFormat ("Yyyy-mm-dd");

System.out.println ("Today is:" +format.format (Calendar.getinstance (). GetTime ()));

System.out.println ("Yesterday is:" +format.format (Cal.gettime ()));

Get 2007-12-25 Date:

Java code

Calendar calendar = new GregorianCalendar (2007, 11, 25,0,0,0);

Date date = Calendar.gettime ();

System.out.println ("Christmas is:" +format.format (date));

The Java month is from 0-11, and the month is set to minus 1.

GregorianCalendar constructor method parameters are: year, month-1, day, time, minute, second.

Take the date part:

Java code

int year =calendar.get (calendar.year);

int Month=calendar.get (calendar.month) +1;

int day =calendar.get (calendar.day_of_month);

int hour =calendar.get (calendar.hour_of_day);

int minute =calendar.get (calendar.minute);

int seconds =calendar.get (calendar.second);

Add 1 to the month you take.

Determine the maximum number of days in the current month:

Java code

Calendar cal = Calendar.getinstance ();

int Day=cal.getactualmaximum (calendar.day_of_month);

System.out.println (day);

2.java.util.date

Java code

Java.util.Date today=new java.util.Date ();

System.out.println ("Today is" +formats.format (today));

Take the first day of the month:

Java code

Java.text.SimpleDateFormat format = new Java.text.SimpleDateFormat ("yyyy-mm-01");

Java.util.Date firstday=new java.util.Date ();

System.out.println ("The Month first day is" +formats.format (FirstDay));

Take the last day of the month:

Java code

Calendar cal = Calendar.getinstance ();

int Maxday=cals.getactualmaximum (calendar.day_of_month);

Java.text.Format formatter3=new Java.text.SimpleDateFormat ("yyyy-mm-" +maxday);

System.out.println (Formatter3.format (Cal.gettime ()));

Find the number of days between two dates:

Java code

Java.text.SimpleDateFormat format = new Java.text.SimpleDateFormat ("Yyyy-mm-dd");

Java.util.Date begindate= format.parse ("2007-12-24");

Java.util.Date enddate= format.parse ("2007-12-25");

Long day= (Date.gettime ()-mydate.gettime ())/(24*60*60*1000);

System.out.println ("number of days apart =" +day);

Date of a year ago:

Java code

Java.text.Format formatter=new Java.text.SimpleDateFormat ("Yyyy-mm-dd");

Java.util.Date todaydate=new java.util.Date ();

Long Beforetime= (Todaydate.gettime ()/1000) -60*60*24*365;

Todaydate.settime (beforetime*1000);

String Beforedate=formatter.format (todaydate);

System.out.println (beforedate);

Date of one year:

Java code

Java.text.Format formatter=new Java.text.SimpleDateFormat ("Yyyy-mm-dd");

Java.util.Date todaydate=new java.util.Date ();

Long Aftertime= (Todaydate.gettime ()/1000) +60*60*24*365;

Todaydate.settime (aftertime*1000);

String Afterdate=formatter.format (todaydate);

System.out.println (afterdate);

Ask for 10 hours after the time

Java code

Java.util.Calendar cal=java.util.calendar.getinstance ();

Cal.settime (Dateoper);

Cal.add (java.util.calendar.hour_of_day,10);

System.out.println ("Date:" +forma.format (Cal.gettime ()));

10 hours before the time

Java code

Java.util.Calendar cal=java.util.calendar.getinstance ();

Cal.settime (Dateoper);

Cal.add (JAVA.UTIL.CALENDAR.HOUR_OF_DAY,-10);

System.out.println ("Date:" +forma.format (Cal.gettime ()));

3.java.sql.date
Inherit from Java.util.Date, which is the date type used to manipulate the database

Java code

Java.sql.Date sqldate = new Java.sql.Date (java.sql.Date.valueOf ("2007-12-25"). GetTime ());

Date Comparison: A simple comparison can be directly compared as a string, or you can use the
Java.sql.Date.valueOf ("2007-03-08"). CompareTo (Java.sql.Date.valueOf ("2007-03-18")) Way to compare the size of the date. You can also use Java.util.Date.after (java.util.Date) to compare.

Time difference:
Long Difference=c2.gettimeinmillis ()-c1.gettimeinmillis ();
Days difference: Long day=difference/(3600*24*1000)
Difference Hour: Long hour=difference/(3600*1000)
Minute difference: Long minute=difference/(60*1000)
Difference seconds: Long second=difference/1000

Add:

Java code

DateFormat df=new SimpleDateFormat ("Yyyy-mm-dd EE hh:mm:ss");

System.out.println (Df.format (New Date ()));

Date date = new Date ();

DateFormat shortdate=dateformat.getdatetimeinstance (Dateformat.short, Dateformat.short);

DateFormat mediumdate =dateformat.getdatetimeinstance (Dateformat.medium, Dateformat.medium);

DateFormat longdate =dateformat.getdatetimeinstance (Dateformat.long, Dateformat.long);

DateFormat fulldate =dateformat.getdatetimeinstance (Dateformat.full, dateformat.full);

System.out.println (Shortdate.format (date));

System.out.println (Mediumdate.format (date));

System.out.println (Longdate.format (date));

System.out.println (Fulldate.format (date));

08-4-15 3:24

2008-4-15 15:24:31

April 15, 2008 03:24 P.M. 31 seconds

April 15, 2008 Tuesday 03:24 P.M. 31 sec CST

Calendar C = calendar.getinstance ();

C.add (Calendar.month, 1); The current time plus 1 months

System.out.println (Df.format (C.gettime ()));

C.add (Calendar.hour, 3); The current time plus 3 hours

System.out.println (Df.format (C.gettime ()));

C.add (Calendar.year,-2); It's now minus 2 years.

System.out.println (Df.format (C.gettime ()));

C.add (Calendar.day_of_week, 7); The current time plus 7 days

System.out.println (Df.format (C.gettime ()));

Java adds and subtract dates from date class, year plus minus, month plus minus