Learn Java date, calendar date operations _java

This article describes the date-related operations in the Java development process, sharing the following code:

Package JSE;
Import java.io.UnsupportedEncodingException;
Import java.text.ParseException;
Import Java.text.SimpleDateFormat;
Import Java.util.Calendar;
Import Java.util.Date;
 
Import Java.util.Locale; /** * Common Date Operation * * @author Puck * createdate 2015-07-30 22:54:38/public class TestDate {public static void main ( String[] args) throws ParseException, unsupportedencodingexception {Calendar cal = Calendar.getinstance ();//CAL
    . Add (Calendar.day_of_month,-48);
  System.out.println (Datetostring (CAL)); /** * Date Formatted * @param date * @return/public static String datetostring (date date) {//simpled
Ateformat format = new SimpleDateFormat ("Y year mm month DD Day E hh" mm minute ss seconds ", Locale.china);
    SimpleDateFormat format = new SimpleDateFormat ("Y-year m-month D-day E h when M minute s sec", Locale.china); SimpleDateFormat SDF = new SimpleDateFormat ("Yyyy-mm-dd HH:mm:ss", Locale.china);
  Example return Sdf.format (date);
   /** * Date Formatted * @param date * @return*/public static String datetostring (Calendar cal) {return datetostring (Cal.gettime ()); /** * DateString Calendar * * @param date * format:2015-06-16 date * @return Calendar * @t Hrows parseexception */public static Calendar Datestringtocalendar (String datestr) throws ParseException {//Ca
Lendar cal = Calendar.getinstance ();
Cal.clear (); Cal.set (Integer.parseint (date.substring (0, 4)), Integer.parseint (Date.substring (5, 7))-1,//Integer.parseint
(Date.substring (8, 10));
     
    Return cal;
    SimpleDateFormat SDF = new SimpleDateFormat ("Yyyy-mm-dd HH:mm:ss");
    Date date = Sdf.parse (DATESTR);
    Calendar cal = Calendar.getinstance ();
    Cal.settime (date);
  Return cal;
   /** * datestring Date * * @param date * FORMAT:YYYY-MM-DD HH:mm:ss date * @return Calendar * @throws ParseException */public static date Datestringtodate (String date) throws ParseException {SimpLedateformat SDF = new SimpleDateFormat ("Yyyy-mm-dd HH:mm:ss");
  return Sdf.parse (date); /** * Date Convert to Calendar * * @param date * @return/public static Calendar Datetocalendar (
    Date date) {Calendar C1 = calendar.getinstance ();
    C1.settime (date);
  return C1; /** * Calendar Convert to Date * @param cal * @return/public static Date calendartodate (Calendar CA
  L) {return cal.gettime (); /** * Calculates the difference between two dates * * @param date * C1 * @param date * C2 * @return Int[]{year, Mont
    H, Day} */public int[] Calculatedifferday (date d1, date D2) {Calendar C1 = calendar.getinstance ();
    C1.settime (D1);
    Calendar C2 = calendar.getinstance ();
    C1.settime (D2);
  Return Calculatedifferday (c1, C2); /** * Calculates the difference between two dates * * @param calendar * C1 * @param calendar * C2 * @return Int[]{ye AR, Month, day} */public int[] CalculatedifferDay (Calendar c1, calendar C2) {int[] P1 = {C1.get (calendar.year), C1.get (Calendar.month), C1.get (calendar.day_of_m
    Onth)};
    Int[] P2 = {C2.get (calendar.year), C2.get (Calendar.month), C2.get (Calendar.day_of_month)};
    System.out.println ("p1[0]=" + p1[0] + "p1[1]=" + p1[1] + "p1[2]=" + p1[2]);
    System.out.println ("p2[0]=" + p2[0] + "p2[1]=" + p2[1] + "p2[2]=" + p2[2]);
    int year = p2[0]-p1[0];
    int month = (p2[0] * () + p2[1]-((p1[0] *) + p1[1]);
    int day = (int) ((C2.gettimeinmillis ()-C1.gettimeinmillis ())/(24 * 60 * 60 * 1000));
  Return to new int[] {year, month, day};
  /** * Get date on the first day of the week * * @param c * @return/public static calendar Getlastdayofweek (Calendar C)  {//SimpleDateFormat FORMAT2 = new SimpleDateFormat ("Y year M month D Day E h time m minute s sec", locale.china);//System.out.println ("Current time:" +
    Format2.format (C.gettime ()));
C.set (Calendar.day_of_week, calendar.monday); System.out.println ("Monday time:" + Format2.format (C.GEttime ()));
  return C;  /** * Date plus minus * @param c * @param day * @return/public static calendar addordecreaseday (Calendar C,
    int day) {C.add (Calendar.day_of_month, day);
  return C; /** * Get the last day of the month * @param year * @param month * @return/public static int getlastdayofmonth (int yea
    R, int month) {Calendar c = calendar.getinstance ();
    C.set (year, month-1, 1);
  Return C.getactualmaximum (Calendar.day_of_month); /** * Get the last day of the month * @param cal * @return/public static int getlastdayofmonth (Calendar cal) {RE
  Turn cal.getactualmaximum (calendar.day_of_month);

 }
   
}