Java get the Summary of implementation methods for a specified date

The following summarizes the implementation methods for obtaining a specified date in Java. For more information, seeCopy codeThe Code is as follows:
Format a Date String --> Date or Data --> String

SimpleDateFormat sdf = new SimpleDateFormat ("yyyy-MM-dd ");
Date date = sdf. parse ("2009-11-04"); // String --> Date

String sdate = sdf. format (date ); // Data --> String ======================================== ==================================
Package com. hefeng. test;
Import java. text. DateFormat;
Import java. text. ParsePosition;
Import java. text. SimpleDateFormat;
Import java. util. Calendar;
Import java. util. Date;
Import java. util. GregorianCalendar;
Public class TimeTest {
// Used to globally control the number of weeks in the previous week, this week, and next week
Private int weeks = 0;
Private int MaxDate; // The maximum number of days in January
Private int MaxYear; // The maximum number of days in a year
/**
* @ Param args
*/
Public static void main (String [] args ){
TimeTest tt = new TimeTest ();

System. out. println ("date after 6 months:" + tt. getAfterMonth (6 );
System. out. println ("Get date:" + tt. getNowTime ("yyyy-MM-dd "));
System. out. println ("Get Monday Date:" + tt. getMondayOFWeek ());
System. out. println ("Get the date of Sunday ~ : "+ Tt. getCurrentWeekday ());
System. out. println ("Get last Monday Date:" + tt. getpreviusweekday ());
System. out. println ("Get Sunday Date:" + tt. getpreviusweeksunday ());
System. out. println ("Get next Monday:" + tt. getNextMonday ());
System. out. println ("Get Sunday Date:" + tt. getNextSunday ());
System. out. println ("Get Saturday of the week:" + tt. getNowTime ("yyyy-MM-dd "));
System. out. println ("Get the first day of this month Date:" + tt. getFirstDayOfMonth ());
System. out. println ("Get the last day of the month:" + tt. getdefaday Day ());
System. out. println ("Get last month first day date:" + tt. getpreviusmonthfirst ());
System. out. println ("Get date of last day of last month:" + tt. getpreviusmonthend ());
System. out. println ("Get the first day of next month Date:" + tt. getNextMonthFirst ());
System. out. println ("Get the last day of next month:" + tt. getNextMonthEnd ());
System. out. println ("Get the first day of the year:" + tt. getCurrentYearFirst ());
System. out. println ("Get date of the last day of the current year:" + tt. getCurrentYearEnd ());
System. out. println ("Get the first day of last year:" + tt. getpreviusyearfirst ());
System. out. println ("Get last day date:" + tt. getpreviusyearend ());
System. out. println ("Get the first day of next year:" + tt. getNextYearFirst ());
System. out. println ("Get the last day of next year:" + tt. getNextYearEnd ());
System. out. println ("Get the first day to the last day of the quarter:" + tt. getThisSeasonTime (11 ));
System. out. println ("Get the number of days between two dates ~ 2008-
. 29: "+ TimeTest. getTwoDay "));
}

/**
* Get the date parameter after the specified month (Before) and pass it as a negative number.

*/

Public static String getAfterMonth (int month ){
Calendar c = Calendar. getInstance (); // gets an instance of a Calendar.
SimpleDateFormat sdf = new SimpleDateFormat ("yyyy-MM-dd ");
Date date = null;
Try {
Date = sdf. parse ("2009-11-04"); // the initial date.
} Catch (Exception e ){

}
C. setTime (date); // set the calendar time
C. add (Calendar. MONTH, month); // add 6 months to the Calendar MONTH.
String strDate = sdf. format (c. getTime (); // the date you want to get 6 months later
Return strDate;

}

/**
* Get the number of days between two days.
*/
Public static String getTwoDay (String sj1, String sj2 ){
SimpleDateFormat myFormatter = new SimpleDateFormat ("yyyy-MM-dd ");
Long day = 0;
Try {
Java. util. Date date = myFormatter. parse (sj1 );
Java. util. Date mydate = myFormatter. parse (sj2 );
Day = (date. getTime ()-mydate. getTime ()/(24*60*60*1000 );
} Catch (Exception e ){
Return "";
}
Return day + "";
}
/**
* Returns the day of the week based on a date.
*/
Public static String getWeek (String sdate ){
// Re-convert to time
Date date = TimeTest. strToDate (sdate );
Calendar c = Calendar. getInstance ();
C. setTime (date );
// Int hour = c. get (Calendar. DAY_OF_WEEK );
// The day of the week is stored in hour. The value range is 1 ~ 7
// 1 = Sunday 7 = Saturday, and so on
Return new SimpleDateFormat ("EEEE"). format (c. getTime ());
}
/**
* Convert a short-time string to a time string in yyyy-MM-dd
*/
Public static Date strToDate (String strDate ){
SimpleDateFormat formatter = new SimpleDateFormat ("yyyy-MM-dd ");
ParsePosition pos = new ParsePosition (0 );
Date strtodate = formatter. parse (strDate, pos );
Return strtodate;
}
/**
* Number of days between two times
*
* @ Param date1
* @ Param date2
* @ Return
*/
Public static long getDays (String date1, String date2 ){
If (date1 = null | date1.equals (""))
Return 0;
If (date2 = null | date2.equals (""))
Return 0;
// Convert to Standard Time
SimpleDateFormat myFormatter = new SimpleDateFormat ("yyyy-MM-dd ");
Java. util. Date date = null;
Java. util. Date mydate = null;
Try {
Date = myFormatter. parse (date1 );
Mydate = myFormatter. parse (date2 );
} Catch (Exception e ){
}
Long day = (date. getTime ()-mydate. getTime ()/(24*60*60*1000 );
Return day;
}
// Calculate the last day of the current month and return a string
Public String getDefaultDay (){
String str = "";
SimpleDateFormat sdf = new SimpleDateFormat ("yyyy-MM-dd ");
Calendar lastDate = Calendar. getInstance ();
LastDate. set (Calendar. DATE, 1); // set it to the number 1 of the current month
LastDate. add (Calendar. MONTH, 1); // add a MONTH to the first day of the next MONTH.
LastDate. add (Calendar. DATE,-1); // subtract one day to the last day of the month.
Str = sdf. format (lastDate. getTime ());
Return str;
}
// The first day of last month
Public String getpreviusmonthfirst (){
String str = "";
SimpleDateFormat sdf = new SimpleDateFormat ("yyyy-MM-dd ");
Calendar lastDate = Calendar. getInstance ();
LastDate. set (Calendar. DATE, 1); // set it to the number 1 of the current month
LastDate. add (Calendar. MONTH,-1); // subtract a MONTH and change it to the first day of the next MONTH.
// LastDate. add (Calendar. DATE,-1); // subtract one day to the last day of the month.
Str = sdf. format (lastDate. getTime ());
Return str;
}
// Obtain the first day of the month
Public String getFirstDayOfMonth (){
String str = "";
SimpleDateFormat sdf = new SimpleDateFormat ("yyyy-MM-dd ");
Calendar lastDate = Calendar. getInstance ();
LastDate. set (Calendar. DATE, 1); // set it to the number 1 of the current month
Str = sdf. format (lastDate. getTime ());
Return str;
}
// Obtain the date of Sunday of the week
Public String getCurrentWeekday (){
Weeks = 0;
Int mondayPlus = this. getMondayPlus ();
GregorianCalendar currentDate = new GregorianCalendar ();
CurrentDate. add (GregorianCalendar. DATE, mondayPlus + 6 );
Date Monday = currentDate. getTime ();
DateFormat df = DateFormat. getDateInstance ();
String preMonday = df. format (Monday );
Return preMonday;
}
// Obtain the current day's time
Public String getNowTime (String dateformat ){
Date now = new Date ();
SimpleDateFormat dateFormat = new SimpleDateFormat (dateformat); // optional
For convenience
Modify Date Format
String hehe = dateFormat. format (now );
Return hehe;
}
// Obtain the number of days for which the current date differs from the current Sunday
Private int getMondayPlus (){
Calendar cd = Calendar. getInstance ();
// Obtain the day of the week, Sunday, and Tuesday ......
Int dayOfWeek = cd. get (Calendar. DAY_OF_WEEK)-1; // as per China Monday
As the first
Day, so here we subtract 1
If (dayOfWeek = 1 ){
Return 0;
} Else {
Return 1-dayOfWeek;
}
}
// Obtain the date of this Monday
Public String getMondayOFWeek (){
Weeks = 0;
Int mondayPlus = this. getMondayPlus ();
GregorianCalendar currentDate = new GregorianCalendar ();
CurrentDate. add (GregorianCalendar. DATE, mondayPlus );
Date Monday = currentDate. getTime ();
DateFormat df = DateFormat. getDateInstance ();
String preMonday = df. format (Monday );
Return preMonday;
}
// Obtain the Saturday date of the corresponding week
Public String getSaturday (){
Int mondayPlus = this. getMondayPlus ();
GregorianCalendar currentDate = new GregorianCalendar ();
CurrentDate. add (GregorianCalendar. DATE, mondayPlus + 7 * weeks + 6 );
Date Monday = currentDate. getTime ();
DateFormat df = DateFormat. getDateInstance ();
String preMonday = df. format (Monday );
Return preMonday;
}
// Obtain the date of last week's Sunday
Public String getpreviusweeksunday (){
Weeks = 0;
Weeks --;
Int mondayPlus = this. getMondayPlus ();
GregorianCalendar currentDate = new GregorianCalendar ();
CurrentDate. add (GregorianCalendar. DATE, mondayPlus + weeks );
Date Monday = currentDate. getTime ();
DateFormat df = DateFormat. getDateInstance ();
String preMonday = df. format (Monday );
Return preMonday;
}
// Obtain the date of last week Monday
Public String getpreviusweekday (){
Weeks --;
Int mondayPlus = this. getMondayPlus ();
GregorianCalendar currentDate = new GregorianCalendar ();
CurrentDate. add (GregorianCalendar. DATE, mondayPlus + 7 * weeks );
Date Monday = currentDate. getTime ();
DateFormat df = DateFormat. getDateInstance ();
String preMonday = df. format (Monday );
Return preMonday;
}
// Obtain the date of the next Monday
Public String getNextMonday (){
Weeks ++;
Int mondayPlus = this. getMondayPlus ();
GregorianCalendar currentDate = new GregorianCalendar ();
CurrentDate. add (GregorianCalendar. DATE, mondayPlus + 7 );
Date Monday = currentDate. getTime ();
DateFormat df = DateFormat. getDateInstance ();
String preMonday = df. format (Monday );
Return preMonday;
}
// Obtain the date of Sunday next week
Public String getNextSunday (){
Int mondayPlus = this. getMondayPlus ();
GregorianCalendar currentDate = new GregorianCalendar ();
CurrentDate. add (GregorianCalendar. DATE, mondayPlus + 7 + 6 );
Date Monday = currentDate. getTime ();
DateFormat df = DateFormat. getDateInstance ();
String preMonday = df. format (Monday );
Return preMonday;
}
Private int getMonthPlus (){
Calendar cd = Calendar. getInstance ();
Int monthOfNumber = cd. get (Calendar. DAY_OF_MONTH );
Cd. set (Calendar. DATE, 1); // set the DATE to the first day of the month.
Cd. roll (Calendar. DATE,-1); // roll back one day, that is, the last day
MaxDate = cd. get (Calendar. DATE );
If (monthOfNumber = 1 ){
Return-MaxDate;
} Else {
Return 1-monthOfNumber;
}
}
// Obtain the date of the last day of the previous month
Public String getpreviusmonthend (){
String str = "";
SimpleDateFormat sdf = new SimpleDateFormat ("yyyy-MM-dd ");
Calendar lastDate = Calendar. getInstance ();
LastDate. add (Calendar. MONTH,-1); // minus one MONTH
LastDate. set (Calendar. DATE, 1); // set the DATE to the first day of the current month.
LastDate. roll (Calendar. DATE,-1); // roll back one day, that is, the last day of the month.
Str = sdf. format (lastDate. getTime ());
Return str;
}
// Obtain the date of the first day of the next month
Public String getNextMonthFirst (){
String str = "";
SimpleDateFormat sdf = new SimpleDateFormat ("yyyy-MM-dd ");
Calendar lastDate = Calendar. getInstance ();
LastDate. add (Calendar. MONTH, 1); // minus one MONTH
LastDate. set (Calendar. DATE, 1); // set the DATE to the first day of the current month.
Str = sdf. format (lastDate. getTime ());
Return str;
}
// Obtain the date of the last day of the next month
Public String getNextMonthEnd (){
String str = "";
SimpleDateFormat sdf = new SimpleDateFormat ("yyyy-MM-dd ");
Calendar lastDate = Calendar. getInstance ();
LastDate. add (Calendar. MONTH, 1); // add a MONTH
LastDate. set (Calendar. DATE, 1); // set the DATE to the first day of the current month.
LastDate. roll (Calendar. DATE,-1); // roll back one day, that is, the last day of the month.
Str = sdf. format (lastDate. getTime ());
Return str;
}
// Obtain the date of the last day of next year
Public String getNextYearEnd (){
String str = "";
SimpleDateFormat sdf = new SimpleDateFormat ("yyyy-MM-dd ");
Calendar lastDate = Calendar. getInstance ();
LastDate. add (Calendar. YEAR, 1); // add a YEAR
LastDate. set (Calendar. DAY_OF_YEAR, 1 );
LastDate. roll (Calendar. DAY_OF_YEAR,-1 );
Str = sdf. format (lastDate. getTime ());
Return str;
}
// Obtain the date of the first day of next year
Public String getNextYearFirst (){
String str = "";
SimpleDateFormat sdf = new SimpleDateFormat ("yyyy-MM-dd ");
Calendar lastDate = Calendar. getInstance ();
LastDate. add (Calendar. YEAR, 1); // add a YEAR
LastDate. set (Calendar. DAY_OF_YEAR, 1 );
Str = sdf. format (lastDate. getTime ());
Return str;
}
// Obtain the number of days of the current year
Private int getMaxYear (){
Calendar cd = Calendar. getInstance ();
Cd. set (Calendar. DAY_OF_YEAR, 1); // set the date to the first day of the current year.
Cd. roll (Calendar. DAY_OF_YEAR,-1); // roll back the date for one day.
Int MaxYear = cd. get (Calendar. DAY_OF_YEAR );
Return MaxYear;
}
Private int getYearPlus (){
Calendar cd = Calendar. getInstance ();
Int yearOfNumber = cd. get (Calendar. DAY_OF_YEAR); // obtain the day of the year
Cd. set (Calendar. DAY_OF_YEAR, 1); // set the date to the first day of the current year.
Cd. roll (Calendar. DAY_OF_YEAR,-1); // roll back the date for one day.
Int MaxYear = cd. get (Calendar. DAY_OF_YEAR );
If (yearOfNumber = 1 ){
Return-MaxYear;
} Else {
Return 1-yearOfNumber;
}
}
// Obtain the date of the first day of the current year
Public String getCurrentYearFirst (){
Int yearPlus = this. getYearPlus ();
GregorianCalendar currentDate = new GregorianCalendar ();
CurrentDate. add (GregorianCalendar. DATE, yearPlus );
Date yearDay = currentDate. getTime ();
DateFormat df = DateFormat. getDateInstance ();
String preYearDay = df. format (yearDay );
Return preYearDay;
}
// Obtain the date of the last day of the current year *
Public String getCurrentYearEnd (){
Date date = new Date ();
SimpleDateFormat dateFormat = new SimpleDateFormat ("yyyy"); // optional
Easy repair
Change Date Format
String years = dateFormat. format (date );
Return years + "-12-31 ";
}

// Obtain the date of the first day of the previous year *
Public String getpreviusyearfirst (){
Date date = new Date ();
SimpleDateFormat dateFormat = new SimpleDateFormat ("yyyy"); // optional
Easy repair
Change Date Format
String years = dateFormat. format (date); int years_value = Integer. parseInt
(Years );
Years_value --;
Return years_value + "-1-1 ";
}
// Obtain the date of the last day of the previous year
Public String getpreviusyearend (){
Weeks --;
Int yearPlus = this. getYearPlus ();
GregorianCalendar currentDate = new GregorianCalendar ();
CurrentDate. add (GregorianCalendar. DATE, yearPlus + MaxYear * weeks + (MaxYear-1 ));
Date yearDay = currentDate. getTime ();
DateFormat df = DateFormat. getDateInstance ();
String preYearDay = df. format (yearDay );
GetThisSeasonTime (11 );
Return preYearDay;
}
// Obtain this quarter
Public String getThisSeasonTime (int month ){
Int array [] [] = {1, 2, 3}, {4, 5, 6}, {7, 8, 9}, {10, 11, 12 }};
Int season = 1;
If (month> = 1 & month <= 3 ){
Season = 1;
}
If (month> = 4 & month <= 6 ){
Season = 2;
}
If (month> = 7 & month <= 9 ){
Season = 3;
}
If (month> = 10 & month <= 12 ){
Season = 4;
}
Int start_month = array [season-1] [0];
Int end_month = array [season-1] [2];
Date date = new Date ();
SimpleDateFormat dateFormat = new SimpleDateFormat ("yyyy"); // optional
Easy repair
Change Date Format
String years = dateFormat. format (date );
Int years_value = Integer. parseInt (years );
Int start_days = 1; // years + "-" + String. valueOf (start_month) + "-
"; // GetLastDayOfMonth (years_value, start_month );
Int end_days = getLastDayOfMonth (years_value, end_month );
String seasonDate =
Years_value + "-" + start_month + "-" + start_days + ";" + years_value + "-" + end_month + "-" + end_days;
Return seasonDate;
}
/**
* Obtain the last day of a month.
* @ Param year
* @ Param month
* @ Return last day
*/
Private int getLastDayOfMonth (int year, int month ){
If (month = 1 | month = 3 | month = 5 | month = 7 | month = 8
| Month = 10 | month = 12 ){
Return 31;
}
If (month = 4 | month = 6 | month = 9 | month = 11 ){
Return 30;
}
If (month = 2 ){
If (isLeapYear (year )){
Return 29;
} Else {
Return 28;
}
}
Return 0;
}
/**
* Leap year
* @ Param year
* @ Return
*/
Public boolean isLeapYear (int year ){
Return (year % 4 = 0 & amp; year % 100! = 0) | (year % 400 = 0 );
}