I need the start date and the end date of the current month in Java. When the JSP page is loaded with the current month it should automatically calculate the start and end date of that month. It should be irrespective of the ye开发者_StackOverflow社区ar and month. That is some month has 31 days or 30 days or 28 days. This should satisfy for a leap year too. Can you help me out with that?
For example if I select month May in a list box I need starting date that is 1 and end date that is 31.
There you go:
public Pair<Date, Date> getDateRange() {
Date begining, end;
{
Calendar calendar = getCalendarForNow();
calendar.set(Calendar.DAY_OF_MONTH,
calendar.getActualMinimum(Calendar.DAY_OF_MONTH));
setTimeToBeginningOfDay(calendar);
begining = calendar.getTime();
}
{
Calendar calendar = getCalendarForNow();
calendar.set(Calendar.DAY_OF_MONTH,
calendar.getActualMaximum(Calendar.DAY_OF_MONTH));
setTimeToEndofDay(calendar);
end = calendar.getTime();
}
return Pair.of(begining, end);
}
private static Calendar getCalendarForNow() {
Calendar calendar = GregorianCalendar.getInstance();
calendar.setTime(new Date());
return calendar;
}
private static void setTimeToBeginningOfDay(Calendar calendar) {
calendar.set(Calendar.HOUR_OF_DAY, 0);
calendar.set(Calendar.MINUTE, 0);
calendar.set(Calendar.SECOND, 0);
calendar.set(Calendar.MILLISECOND, 0);
}
private static void setTimeToEndofDay(Calendar calendar) {
calendar.set(Calendar.HOUR_OF_DAY, 23);
calendar.set(Calendar.MINUTE, 59);
calendar.set(Calendar.SECOND, 59);
calendar.set(Calendar.MILLISECOND, 999);
}
PS: Pair
class is simply a pair of two values.
If you have the option, you'd better avoid the horrid Java Date API, and use instead Jodatime (or equivalently the Java 8 java.time.*
API). Here is an example:
LocalDate monthBegin = new LocalDate().withDayOfMonth(1);
LocalDate monthEnd = new LocalDate().plusMonths(1).withDayOfMonth(1).minusDays(1);
Try LocalDate from Java 8:
LocalDate today = LocalDate.now();
System.out.println("First day: " + today.withDayOfMonth(1));
System.out.println("Last day: " + today.withDayOfMonth(today.lengthOfMonth()));
Simple and Best, Try this One
Calendar calendar = Calendar.getInstance();
calendar.add(Calendar.MONTH, 0);
calendar.set(Calendar.DATE, calendar.getActualMinimum(Calendar.DAY_OF_MONTH));
Date monthFirstDay = calendar.getTime();
calendar.set(Calendar.DATE, calendar.getActualMaximum(Calendar.DAY_OF_MONTH));
Date monthLastDay = calendar.getTime();
SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd");
String startDateStr = df.format(monthFirstDay);
String endDateStr = df.format(monthLastDay);
Log.e("DateFirstLast",startDateStr+" "+endDateStr);
Calendar c = Calendar.getInstance();
int year = c.get(Calendar.YEAR);
int month = c.get(Calendar.MONTH);
int day = 1;
c.set(year, month, day);
int numOfDaysInMonth = c.getActualMaximum(Calendar.DAY_OF_MONTH);
System.out.println("First Day of month: " + c.getTime());
c.add(Calendar.DAY_OF_MONTH, numOfDaysInMonth-1);
System.out.println("Last Day of month: " + c.getTime());
With the date4j library :
dt.getStartOfMonth();
dt.getEndOfMonth();
Try this Code
Calendar calendar = Calendar.getInstance();
int yearpart = 2010;
int monthPart = 11;
int dateDay = 1;
calendar.set(yearpart, monthPart, dateDay);
int numOfDaysInMonth = calendar.getActualMaximum(Calendar.DAY_OF_MONTH);
System.out.println("Number of Days: " + numOfDaysInMonth);
System.out.println("First Day of month: " + calendar.getTime());
calendar.add(Calendar.DAY_OF_MONTH, numOfDaysInMonth-1);
System.out.println("Last Day of month: " + calendar.getTime());
Hope it helps.
if you have java.time.YearMonth
you can do:
YearMonth startYearMonth = YearMonth.now();
java.time.LocalDate startOfMonthDate = startYearMonth.atDay(1);
java.time.LocalDate endOfMonthDate = startYearMonth.atEndOfMonth();
Date begining, ending;
Calendar calendar_start =BusinessUnitUtility.getCalendarForNow();
calendar_start.set(Calendar.DAY_OF_MONTH,calendar_start.getActualMinimum(Calendar.DAY_OF_MONTH));
begining = calendar_start.getTime();
String start= DateDifference.dateToString(begining,"dd-MMM-yyyy");//sdf.format(begining);
// for End Date of month
Calendar calendar_end = BusinessUnitUtility.getCalendarForNow();
calendar_end.set(Calendar.DAY_OF_MONTH,calendar_end.getActualMaximum(Calendar.DAY_OF_MONTH));
ending = calendar_end.getTime();
String end=DateDifference.dateToString(ending,"dd-MMM-yyyy");//or sdf.format(end);
enter code here
public static Calendar getCalendarForNow() {
Calendar calendar = GregorianCalendar.getInstance();
calendar.setTime(new Date());
return calendar;
}
For Java 8+, below method will given current month first & last dates as LocalDate instances.
public static LocalDate getCurrentMonthFirstDate() {
return LocalDate.ofEpochDay(System.currentTimeMillis() / (24 * 60 * 60 * 1000) ).withDayOfMonth(1);
}
public static LocalDate getCurrentMonthLastDate() {
return LocalDate.ofEpochDay(System.currentTimeMillis() / (24 * 60 * 60 * 1000) ).plusMonths(1).withDayOfMonth(1).minusDays(1);
}
Side note: Using LocalDate.ofEpochDay(...)
instead of LocalDate.now()
gives much improved performance. Also, using the millis-in-a-day expression instead of the end value, which is 86400000
is performing better. I initially thought the latter would perform better than the the expression :P
public static void main(String[] args)
{
LocalDate today = LocalDate.now();
System.out.println("First day: " +
today.withDayOfMonth(1));
System.out.println("Last day: " + today.withDayOfMonth(today.lengthOfMonth()))
}
You can implement it as below:
public void FirstAndLastDate() {
SimpleDateFormat sdf = new SimpleDateFormat("yyy-MM-dd");
//start date of month
calendarStart = Calendar.getInstance();
calendarStart.set(Integer.parseInt((new SimpleDateFormat("yyyy")).format(new Date().getTime()))
, Integer.parseInt((new SimpleDateFormat("MM")).format(new Date().getTime()))
, Calendar.getInstance().getActualMinimum(Calendar.DAY_OF_MONTH));
//End Date of month
calendarEnd = Calendar.getInstance();
calendarEnd.set(Integer.parseInt((new SimpleDateFormat("yyyy")).format(new Date().getTime()))
, Integer.parseInt((new SimpleDateFormat("MM")).format(new Date().getTime()))
, Calendar.getInstance().getActualMaximum(Calendar.DAY_OF_MONTH));
Toast.makeText(this, sdf.format(calendarStart.getTime()) + "\n" + sdf.format(calendarEnd.getTime()), Toast.LENGTH_SHORT).show();
}
A very simple step to get the first day and last day of the month:
Calendar calendar = Calendar.getInstance();
// Get the current date
Date today = calendar.getTime();
// Setting the first day of month
calendar.set(Calendar.DAY_OF_MONTH, 1);
Date firstDayOfMonth = calendar.getTime();
// Move to next month
calendar.add(Calendar.MONTH, 1);
// setting the 1st day of the month
calendar.set(Calendar.DAY_OF_MONTH, 1);
// Move a day back from the date
calendar.add(Calendar.DATE, -1);
Date lastDayOfMonth = calendar.getTime();
// Formatting the date
DateFormat sdf = new SimpleDateFormat("dd-MMM-YY");
String todayStr = sdf.format(today);
String firstDayOfMonthStr = sdf.format(firstDayOfMonth);
String lastDayOfMonthStr = sdf.format(lastDayOfMonth);
System.out.println("Today : " + todayStr);
System.out.println("Fist Day of Month: "+firstDayOfMonthStr);
System.out.println("Last Day of Month: "+lastDayOfMonthStr);
Making it more modular, you can have one main function that calculates startDate or EndDate and than you can have individual methods to getMonthStartDate
, getMonthEndDate
and to getMonthStartEndDate
. Use methods as per your requirement.
public static String getMonthStartEndDate(){
String start = getMonthDate("START");
String end = getMonthDate("END");
String result = start + " to " + end;
return result;
}
public static String getMonthStartDate(){
String start = getMonthDate("START");
return start;
}
public static String getMonthEndDate(){
String end = getMonthDate("END");
return end;
}
/**
* @param filter
* START for start date of month e.g. Nov 01, 2013
* END for end date of month e.g. Nov 30, 2013
* @return
*/
public static String getMonthDate(String filter){
String MMM_DD_COMMA_YYYY = "MMM dd, yyyy";
SimpleDateFormat sdf = new SimpleDateFormat(MMM_DD_COMMA_YYYY);
sdf.setTimeZone(TimeZone.getTimeZone("PST"));
sdf.format(GregorianCalendar.getInstance().getTime());
Calendar cal = GregorianCalendar.getInstance();
int date = cal.getActualMinimum(Calendar.DATE);
if("END".equalsIgnoreCase(filter)){
date = cal.getActualMaximum(Calendar.DATE);
}
cal.set(Calendar.DATE, date);
String result = sdf.format(cal.getTime());
System.out.println(" " + result );
return result;
}
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