Date text box should be always 1st date current month.? - java

I want a javascript or java program should always give date 1st of current month.
Is there any tech?

You can use Calendar for Java
Date date = new Date(System.currentTimeMillis());
cal = Calendar.getInstance();
cal.setTime(date);
cal.set(Calendar.DAY_OF_MONTH, 1);
Now you do what every you want to do with this Calendar object like to get the Day of the Week (Sat, Sun, .... )
int weekday = cal.get(Calendar.DAY_OF_WEEK);
And for JavaScript you can use:
var theFirst = new Date();
theFirst.setDate(1);
setDate sets the day of the month for the Date object (from 1 to 31). Then you can do whatever you want with theFirst, like get the day of the week.

Calendar ans = Calendar.getInstance();
ans.set(ans.get(Calendar.YEAR),
ans.get(Calendar.MONTH),
1,
0,
0,
0
);
System.out.println(ans.getTime());

Related

How do find day number(integer) of last day in the current month

I have specific date and i want to find last day number(integer) of month. I am using following code but always return current of date.
DateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
Date date = (Date) sdf.parse(year+"-"+(month<10?("0"+month):month)+"-01");
Calendar calendar = Calendar.getInstance();
calendar.setTime(date);
calendar.add(Calendar.MONTH, 1);
calendar.set(Calendar.DAY_OF_MONTH, 1);
calendar.add(Calendar.DATE, -1);
Date dt = (Date) calendar.getTime(); -> dt is return current date always
example: my date = 2018/04/30 and i want to find 30.
I couldnt find answer at site.
Thnx
If using Java 8 (or higher), don't use Calendar. If using Java 6 or 7, you might want to consider using the ThreeTen Backport. In either case, use the Java Time API.
Using Java Time
Since input is int year and int month, use YearMonth.
To find last day number of month, call lengthOfMonth().
To get the date at the end of month, call atEndOfMonth().
Demo
int year = 2020;
int month = 2;
int lastDay = YearMonth.of(year, month).lengthOfMonth();
System.out.println(lastDay);
LocalDate date = YearMonth.of(year, month).atEndOfMonth();
System.out.println(date);
Output
29
2020-02-29
Using Joda-Time
If you don't have Java 8, and already use Joda-Time, do it this way:
Demo
int year = 2020;
int month = 2;
int lastDay = new LocalDate(year, month, 1).dayOfMonth().getMaximumValue();
System.out.println(lastDay);
LocalDate date = new LocalDate(year, month, 1).dayOfMonth().withMaximumValue();
System.out.println(date);
Output
29
2020-02-29
Using Calendar
If you insist on using Calendar, call getActualMaximum(Calendar.DAY_OF_MONTH) as also mentioned in other answers.
Since input is int year and int month, don't build and parse a string, just set Calendar fields directly. Note that "month" in Calendar is zero-based.
Demo
int year = 2020;
int month = 2;
Calendar calendar = Calendar.getInstance();
calendar.clear();
calendar.set(year, month - 1, 1);
int lastDay = calendar.getActualMaximum(Calendar.DAY_OF_MONTH);
calendar.set(Calendar.DAY_OF_MONTH, lastDay);
Date date = calendar.getTime();
System.out.println(lastDay);
System.out.printf("%tF%n", date);
Output
29
2020-02-29
have specific date and i want to find last day number(integer) of month
getActualMaximum() is what you are looking for here.
Calendar cal = Calendar.getInstance();
cal.setTime(parsedDate);
cal.getActualMaximum(Calendar.DAY_OF_MONTH);
Calendar calendar =Calendar.getInstance();
calendar.set(Calendar.DATE, 1);
calendar.roll(Calendar.DATE, -1);
int lastDate=calendar.get(Calendar.DATE);
You can use calendar for that, like this:
calendar.getActualMaximum(Calendar.DAY_OF_MONTH);
Or, if you have joda, which is usually better:
DateTime d = new DateTame(dt);
d.dayOfMonth().getMaximumValue();
First, how are you getting the year to be used?
it should be simple by using Java Time LocalDate:
import java.time.*;
import static java.time.Month.*;
import static java.time.temporal.TemporalAdjusters.*;
import static java.time.temporal.ChronoField.*;
int lastDay = LocalDate.now() // or whatever date you want
.with(Month.of(yourMonth))
.with(lastDayOfMonth())
.get(DAY_OF_MONTH);
// or, if you have year and month, and want to find the corresponding last day
int lastDay = LocalDate.of(yourYear, yourMonth, 1)
.with(lastDayOfMonth())
.get(DAY_OF_MONTH);

how to get next month date from specified date in Android

I'm designing a program where in my recylerview i wanted to display a list of items whose date is 4 days less or more than current date.
This will work for month:
Calendar cal = Calendar.getInstance();
cal.add(Calendar.MONTH, 1);
This will work for -4 day:
Calendar cal = Calendar.getInstance();
cal.add(Calendar.DAY_OF_MONTH, -4);

Convert changed GregorianCalendar to Date

I have the following code in a method:
final String WEEK_OF_YEAR = "w";
GregorianCalendar calendar = new GregorianCalendar();
calendar.set(Calendar.WEEK_OF_YEAR, Integer.valueOf(get(WEEK_OF_YEAR)) + 1);
//The get(WEEK_OF_YEAR) returns the actual week of the year
DateFormat formatter = new SimpleDateFormat("EE, dd.MM.yyyy");
return formatter.format(calendar.getTime());
so what I want is to get a String of the format "EE, dd.MM.yyyy" of the next week.
so it looks like that calendar.getTime() is returning the actual week...
If you want the next week, use this code:
GregorianCalendar calendar = new GregorianCalendar();
calendar.add(Calendar.WEEK_OF_YEAR, 1);
Note that new Calender() returns the current week. I do not know GregorianCalendar(). You may have a try.

How to get calendar from date

I have some date and I want to get last x day before this date so this is my code:
Calendar today = Calendar.getInstance();
today.add(Calendar.DATE, -x);
date = new Date(today.getTimeInMillis()))
this code works only if some day is actual day. How I can change it. Is there some method to get calendar from date ?
Use the setTime method to set the date of your calendar :
Calendar aDay = Calendar.getInstance();
aDay.setTime(aDate);

last day of month calculation

I am having issues with the calculation of when the next Last Day of the Month is for a notification which is scheduled to be sent.
Here is my code:
RecurrenceFrequency recurrenceFrequency = notification.getRecurrenceFrequency();
Calendar nextNotifTime = Calendar.getInstance();
This is the line causing issues I believe:
nextNotifTime.add(recurrenceFrequency.getRecurrencePeriod(),
recurrenceFrequency.getRecurrenceOffset());
How can I use the Calendar to properly set the last day of the next month for the notification?
Calendar.getInstance().getActualMaximum(Calendar.DAY_OF_MONTH);
This returns actual maximum for current month. For example it is February of leap year now, so it returns 29 as int.
java.time.temporal.TemporalAdjusters.lastDayOfMonth()
Using the java.time library built into Java 8, you can use the TemporalAdjuster interface. We find an implementation ready for use in the TemporalAdjusters utility class: lastDayOfMonth.
import java.time.LocalDate;
import java.time.temporal.TemporalAdjusters;
LocalDate now = LocalDate.now(); //2015-11-23
LocalDate lastDay = now.with(TemporalAdjusters.lastDayOfMonth()); //2015-11-30
If you need to add time information, you may use any available LocalDate to LocalDateTime conversion like
lastDay.atStartOfDay(); //2015-11-30T00:00
And to get last day as Date object:
Calendar cal = Calendar.getInstance();
cal.set(Calendar.DATE, cal.getActualMaximum(Calendar.DATE));
Date lastDayOfMonth = cal.getTime();
You can set the calendar to the first of next month and then subtract a day.
Calendar nextNotifTime = Calendar.getInstance();
nextNotifTime.add(Calendar.MONTH, 1);
nextNotifTime.set(Calendar.DATE, 1);
nextNotifTime.add(Calendar.DATE, -1);
After running this code nextNotifTime will be set to the last day of the current month. Keep in mind if today is the last day of the month the net effect of this code is that the Calendar object remains unchanged.
Following will always give proper results:
Calendar cal = Calendar.getInstance();
cal.set(Calendar.MONTH, ANY_MONTH);
cal.set(Calendar.YEAR, ANY_YEAR);
cal.set(Calendar.DAY_OF_MONTH, 1);// This is necessary to get proper results
cal.set(Calendar.DATE, cal.getActualMaximum(Calendar.DATE));
cal.getTime();
You can also use YearMonth.
Like:
YearMonth.of(2019,7).atEndOfMonth()
YearMonth.of(2019,7).atDay(1)
See
https://docs.oracle.com/javase/8/docs/api/java/time/YearMonth.html#atEndOfMonth--
Using the latest java.time library here is the best solution:
LocalDate date = LocalDate.now();
LocalDate endOfMonth = date.with(TemporalAdjusters.lastDayOfMonth());
Alternatively, you can do:
LocalDate endOfMonth = date.withDayOfMonth(date.lengthOfMonth());
Look at the getActualMaximum(int field) method of the Calendar object.
If you set your Calendar object to be in the month for which you are seeking the last date, then getActualMaximum(Calendar.DAY_OF_MONTH) will give you the last day.
SimpleDateFormat sdf = new SimpleDateFormat("dd/MM/yyyy");
Date date = sdf.parse("11/02/2016");
Calendar calendar = Calendar.getInstance();
calendar.setTime(date);
System.out.println("First Day Of Month : " + calendar.getActualMinimum(Calendar.DAY_OF_MONTH));
System.out.println("Last Day of Month : " + calendar.getActualMaximum(Calendar.DAY_OF_MONTH));
Kotlin date extension implementation using java.util.Calendar
fun Date.toEndOfMonth(): Date {
return Calendar.getInstance().apply {
time = this#toEndOfMonth
}.toEndOfMonth().time
}
fun Calendar.toEndOfMonth(): Calendar {
set(Calendar.DAY_OF_MONTH, getActualMaximum(Calendar.DAY_OF_MONTH))
return this
}
You can call toEndOfMonth function on each Date object like Date().toEndOfMonth()

Categories