Android Tool Class Dateutil

Some date-related functions that may be used in the development process are extracted as tool classes for your reference:

/** * Date manipulation tool class. * * @author Shimiso */public class Dateutil {private static final String FORMAT = "Yyyy-mm-dd HH:mm:ss";p ublic static Dat e str2date (String str) {return str2date (str, NULL);} public static Date str2date (String str, string format) {if (str = = NULL | | str.length () = = 0) {return null;} if (format = = NULL | | format.length () = = 0) {format = format;} Date date = null;try {SimpleDateFormat sdf = new SimpleDateFormat (format);d ate = Sdf.parse (str);} catch (Exception e) {E.P Rintstacktrace ();} return date;} public static Calendar Str2calendar (String str) {return Str2calendar (str, NULL);} public static Calendar Str2calendar (String str, string format) {Date date = str2date (str, format); if (Date = = null) {retur n NULL;} Calendar C = calendar.getinstance (); C.settime (date); return C;} public static String Date2str (Calendar c) {//Yyyy-mm-dd HH:mm:ssreturn date2str (c, null);} public static string Date2str (Calendar C, string format) {if (c = = null) {return null;} Return Date2str (C.gettime (), format);}public static String date2str (Date D) {//YYYY-MM-DD HH:mm:ssreturn date2str (d, null);} public static string Date2str (Date D, string format) {//Yyyy-mm-dd HH:mm:ssif (d = = null) {return null;} if (format = = NULL | | format.length () = = 0) {format = format;} SimpleDateFormat SDF = new SimpleDateFormat (format); String s = sdf.format (d); return s;} public static String Getcurdatestr () {Calendar c = calendar.getinstance (); C.settime (new Date ()); return C.get ( Calendar.year) + "-" + (C.get (calendar.month) + 1) + "-" + c.get (calendar.day_of_month) + "-" + c.get (calendar.hour_of_day) + ":" + c.get (Calendar.minute) + ":" + c.get (Calendar.second);} /** * Get the current date string format * * @param format * @return */public static string getcurdatestr (string format) {Calendar c = Calendar . getinstance (); return Date2str (c, format);} Format to seconds public static String Getmillon (long time) {return new SimpleDateFormat ("Yyyy-mm-dd-hh-mm-ss"). Format (time);} Format to day public static String GetDay (long time) {return new SimpleDateFormat ("yyyy-mm-dD "). Format (time);} Format to Ms public static String Getsmillon (long time) {return new SimpleDateFormat ("Yyyy-mm-dd-hh-mm-ss-sss"). Format (Time );} /* Input is a string, format such as 20120102, to implement the function of the day, the returned format is string, such as 20120103 */public static string Stringdateplus (String row) throws Parseexception{string year=row.substring (0, 4); String month=row.substring (4,6); String day=row.substring (6); String date1=year+ "-" +month+ "-" +day; SimpleDateFormat sdf=new SimpleDateFormat ("YYYY-MM-DD");D ate Startdate=sdf.parse (date1);  Calendar cd = Calendar.getinstance (); Cd.settime (StartDate); Cd.add (calendar.date, 1); String datestr =sdf.format (Cd.gettime ()); String year1=datestr.substring (0,4); String month1=datestr.substring (5,7); String day1=datestr.substring (8); return year1+month1+day1;} /* Input is a string, format such as 20120102, to implement the function of reducing the day, the returned format is string, such as 20120101 */public static string Stringdatedecrease (String row) Throws Parseexception{string year=row.substring (0, 4); String month=row.substring (4,6); String day=row.substring (6); String date1=year+ "-" +montH + "-" +day; SimpleDateFormat sdf=new SimpleDateFormat ("YYYY-MM-DD");D ate Startdate=sdf.parse (date1);  Calendar cd = Calendar.getinstance (); Cd.settime (StartDate); Cd.add (Calendar.date,-1); String datestr =sdf.format (Cd.gettime ()); String year1=datestr.substring (0,4); String month1=datestr.substring (5,7); String day1=datestr.substring (8); return year1+month1+day1;} /* The format of the input is string, such as 20120101, and the format returned is string, such as 2012-01-01 */public static string Stringdatechange (string date) {if ( Date.length () = = "20120101". Length ()) {String year=date.substring (0, 4); String month=date.substring (4,6); String day=date.substring (6); return year+ "-" +month+ "-" +day;} Else{return date;}} /** * Date pushed backwards day * @param date format: 20120101 * @return 20120102 */public static string Tonextday (string date) {int year = Inte Ger.parseint (date.substring (0,4)); int month = Integer.parseint (date.substring (4,6)); int day = Integer.parseint ( Date.substring (6)); Calendar calendar = Calendar.getinstance (); Calendar.set (year, month-1, day+1);D ate newdate = CalendaR.gettime (); SimpleDateFormat format = new SimpleDateFormat ("YyyyMMdd"); String da = Format.format (newdate); return da;} public static void Main (string[] args) {new Stringhandle (). Previousweekenddaybydate ("20130109");} /** * Gets the start date of the previous week of the current date (Sunday) */public static string previousweekbydate (String date) {int year = Integer.parseint (Date.substri Ng (0,4)); int month = Integer.parseint (date.substring (4,6)); int day = Integer.parseint (date.substring (6)); Calendar calendar = Calendar.getinstance (); Calendar.set (year, month-1, day);D ate newdate = Calendar.gettime ();     SimpleDateFormat sdf=new SimpleDateFormat ("YyyyMMdd");    Calendar cal = Calendar.getinstance ();    Cal.settime (newdate);     int dayweek = Cal.get (Calendar.day_of_week);//Get the current date is the day of the one week if (1 = = DayWeek) {Cal.add (Calendar.day_of_month,-1); } cal.setfirstdayofweek (Calendar.sunday);//Set one the first day of the week, according to the Chinese habit one weeks the first day is Monday int s = cal.get (Calendar.day_of_week); /Get the current date is the day of the one week Cal.add (Calendar.date, Cal.getfirstdayofweek ()-s);//According to the rules of the calendar, the difference between the current date and the first day of the week of one weeks is reduced to cal.add (Calendar.week_of_year,-1);    String Imptimebegin = Sdf.format (Cal.gettime ());//System.out.println ("Date of week Sunday:" +imptimebegin); return imptimebegin;} /** * Gets the end date of the previous week of the current date (Saturday) */public static string previousweekenddaybydate (String date) {int year = Integer.parseint (date.s Ubstring (0,4)); int month = Integer.parseint (date.substring (4,6)); int day = Integer.parseint (date.substring (6)); Calendar calendar = Calendar.getinstance (); Calendar.set (year, month-1, day);D ate newdate = Calendar.gettime ();     SimpleDateFormat sdf=new SimpleDateFormat ("YyyyMMdd");    Calendar cal = Calendar.getinstance ();    Cal.settime (newdate);     int dayweek = Cal.get (Calendar.day_of_week);//Get the current date is the day of the one week if (1 = = DayWeek) {Cal.add (Calendar.day_of_month,-1); } cal.setfirstdayofweek (Calendar.sunday);//Set one the first day of the week, according to the Chinese habit one weeks the first day is Monday int s = cal.get (Calendar.day_of_week);    /Get the current date is the day of the one week Cal.add (Calendar.date, Cal.getfirstdayofweek () + (6-s)); Cal.add (CALENDAR.WEek_of_year,-1);    String Imptimebegin = Sdf.format (Cal.gettime ());//System.out.println ("Saturday Date:" +imptimebegin); return imptimebegin;} /** * Gets the current day of the current week start date (Sunday) */public static string getcurrentweekfirstdaybydate (String date) {int year = Integer.parseint (d Ate.substring (0,4)); int month = Integer.parseint (date.substring (4,6)); int day = Integer.parseint (date.substring (6)); Calendar calendar = Calendar.getinstance (); Calendar.set (year, month-1, day);D ate newdate = Calendar.gettime ();     SimpleDateFormat sdf=new SimpleDateFormat ("YyyyMMdd");    Calendar cal = Calendar.getinstance ();    Cal.settime (newdate);     int dayweek = Cal.get (Calendar.day_of_week);//Get the current date is the day of the one week if (1 = = DayWeek) {Cal.add (Calendar.day_of_month,-1); } cal.setfirstdayofweek (Calendar.sunday);//Set one the first day of the week, according to the Chinese habit one weeks the first day is Monday int s = cal.get (Calendar.day_of_week); /Get the current date is the day of the one week Cal.add (Calendar.date, Cal.getfirstdayofweek ()-s);//According to calendar rules, the difference between the current date and the first day of the week and one weeks is reduced to String imptime Begin = Sdf.formaT (Cal.gettime ());    System.out.println ("Date of week Sunday:" +imptimebegin); return imptimebegin;} /** * Gets the current date end date of the current week (Saturday) */public static string getcurrentweekenddaybydate (String date) {int year = Integer.parseint (dat E.substring (0,4)); int month = Integer.parseint (date.substring (4,6)); int day = Integer.parseint (date.substring (6)); Calendar calendar = Calendar.getinstance (); Calendar.set (year, month-1, day);D ate newdate = Calendar.gettime ();     SimpleDateFormat sdf=new SimpleDateFormat ("YyyyMMdd");    Calendar cal = Calendar.getinstance ();    Cal.settime (newdate);     int dayweek = Cal.get (Calendar.day_of_week);//Get the current date is the day of the one week if (1 = = DayWeek) {Cal.add (Calendar.day_of_month,-1); } cal.setfirstdayofweek (Calendar.sunday);//Set one the first day of the week, according to the Chinese habit one weeks the first day is Monday int s = cal.get (Calendar.day_of_week);      /Get the current date is the day of the one week Cal.add (Calendar.date, Cal.getfirstdayofweek () + (6-s));    String Imptimebegin = Sdf.format (Cal.gettime ()); return imptimebegin;} /** * Return the first day of the last one months * @param date20120304 * @return 20120201 */public static string previousmonthbydate (String date) {//TODO auto-generated method Stubint Year = Integer.parseint (date.substring (0,4)); int month = Integer.parseint (date.substring (4,6)); int day = Integer.parseint ( Date.substring (6)); Calendar calendar = Calendar.getinstance (); Calendar.set (year, month-2, 1);D ate newdate = Calendar.gettime ();     SimpleDateFormat sdf=new SimpleDateFormat ("YyyyMMdd");    Calendar cal = Calendar.getinstance ();    Cal.settime (newdate); String Imptimebegin = Sdf.format (Cal.gettime ());//System.out.println (Imptimebegin); return imptimebegin;} /** * Returns the first day of the next one months * @param date20120304 * @return 20120401 */public static string Nextmonthbydate (string date) {//TODO Au To-generated method Stubint year = Integer.parseint (date.substring (0,4)); int month = Integer.parseint (date.substring ( 4,6)); int day = Integer.parseint (date.substring (6)); Calendar calendar = Calendar.getinstance (); Calendar.set (year, month, 1);D ate newdate = Calendar.gettime (); SimPledateformat sdf=new SimpleDateFormat ("YyyyMMdd");    Calendar cal = Calendar.getinstance ();    Cal.settime (newdate); String Imptimebegin = Sdf.format (Cal.gettime ());//System.out.println (Imptimebegin); return imptimebegin;} /** * Returns the first day of the current month * @param date20120103 * @return 20120101 */public static string Getcurrentmonthfirstdaybydate (string date {int year = Integer.parseint (date.substring (0,4)), int month = Integer.parseint (date.substring (4,6)); Int day = Integer.parseint (date.substring (6)); Calendar calendar = Calendar.getinstance (); Calendar.set (year, month-1, 1);D ate newdate = Calendar.gettime ();     SimpleDateFormat sdf=new SimpleDateFormat ("YyyyMMdd");    Calendar cal = Calendar.getinstance ();    Cal.settime (newdate); String Imptimebegin = Sdf.format (Cal.gettime ()); return imptimebegin;}}