Java date Plus and minus operations

1. Use java. util. Calender to achieve

Calendar calendar=calendar.getinstance ();
Calendar.settime (New Date ());
System.out.println (Calendar.get (Calendar.day_of_month));//Today's date
Calendar.set (Calendar.day_of_month,calendar.get (calendar.day_of_month) +1);//Let date plus 1
System.out.println (Calendar.get (calendar.date));//top of date plus 1
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2. Use Java. Text. SimpleDateFormat and Java. util. Date to implement

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 ()-2 * 24 * 60 * 60 * 1000)));
System.out.println ("Date after three days:" + df.format (new Date (D.gettime () + 3 * 24 * 60 * 60 * 1000)));

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GregorianCalendar gc=new GregorianCalendar ();
Gc.settime (new Date);
Gc.add (Field,value);
Value is positive, backward, negative, forward
Field take 1 plus 1 years, take 2 plus six months, take 3 plus one quarter, take 4 plus one week
Take 5 plus a day ....

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/*
* Addition and subtraction of dates inJava
*gc.add (1,-1) represents the year minus one.
*gc.add (2,-1) represents the month minus one.
*gc.add (3.-1) means weekly minus one.
*gc.add (5,-1) represents a day minus one.
* And so should be accurate milliseconds. No, try again. You can try it.
The Add (int field,int amount) method of the *gregoriancalendar class represents the month-date plus minus.
The *field parameter represents the year, month, and day.
The *amount parameter represents the quantity to be added and reduced.
*
* Usedate. The Java tests are as follows:
*/
Package temp.util;

Import java. util. Calendar;
Import java. util. Date;
Import java. util. GregorianCalendar;
Import java. Text. SimpleDateFormat;
public class Usedate {

Date D=new date ();
GregorianCalendar GC =new GregorianCalendar ();
SimpleDateFormat SF =new simpledateformat ("Yyyy-mm-dd");

Public String Getyears ()
{
Gc.settime (d);
Gc.add (1,+1);
Gc.set (Gc.get (calendar.year), Gc.get (Calendar.month), Gc.get (calendar.date));

Return Sf.format (Gc.gettime ());
}

Public String gethalfyear ()
{
Gc.settime (d);
Gc.add (2,+6);
Gc.set (Gc.get (calendar.year), Gc.get (Calendar.month), Gc.get (calendar.date));

Return Sf.format (Gc.gettime ());
}
Public String getquarters ()
{
Gc.settime (d);
Gc.add (2,+3);
Gc.set (Gc.get (calendar.year), Gc.get (Calendar.month), Gc.get (calendar.date));

Return Sf.format (Gc.gettime ());
}

Public String getlocaldate ()
{
Return Sf.format (d);
}

public static void Main (string[] args)
{
Usedate ud= new Usedate ();
System.out.println (Ud.getlocaldate ());
System.out.println (Ud.getyears ());
System.out.println (Ud.gethalfyear ());
System.out.println (Ud.getquarters ());
}

}

4,

GregorianCalendar gc=new GregorianCalendar ();

try {
Gc.settime (New SimpleDateFormat ("Yyyymm"). Parse ("200901"));
Gc.add (2,-integer.parseint ("7"));
} catch (ParseException e) {
TODO Auto Generate されたcatchブロック
E.printstacktrace ();
}
System.out.println (New SimpleDateFormat ("Yyyymm"). Format (Gc.gettime ()));

Run Result: 200806

Java date Plus and minus operations