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How to get week of selected date in java?

How to get week of particular selected date?
For Example:
My week will start from Monday and ends on Sunday.
So lets say i have selected 25 July 2017. So i want what was the date on monday of that week and what is the date on upcoming Sunday of that week.
The answer should be :: Monday -- 24 July 2017 AND Sunday-- 30 July 2017.
I am not able to find a simple way to get it.

You can see this. It is for the present date.
Calendar cal = Calendar.getInstance();
int week = cal.get(Calendar.WEEK_OF_MONTH);
int day = cal.get(Calendar.DAY_OF_WEEK);
System.out.println(day);
Date mondayDate = null;
if (day > 2) {
int monday = day - 2;
cal.add(Calendar.DATE, -monday);
mondayDate = cal.getTime();
} else {
// cal.add(Calendar.DATE,);
mondayDate = cal.getTime();
}
int sunday = 7 - day + 1;
cal.add(Calendar.DATE, +sunday);
Date sundaydate = cal.getTime();
System.out.println(mondayDate);
System.out.println(sundaydate);
}
In this, we are finding the day of the week.Today we will get
day=2.
Now for monday,we will first check days.
if day=1, means it is sunday.
if day=2, means it is monday.
so for day>2, we are getting date of (day-2) days back. For today, day=1. hence mondaydate= 23 July,2017.
Similarily for sunday, we are getting date of (7-day+1) days later. For today, sunday=5, so after +6, sundaydate= 31 july,2017
Hope this helps :)

You can get like this :
String date = (String) android.text.format.DateFormat.format("dd", date);
String dayOfTheWeek = (String) DateFormat.format("EEEE", date);
For next Sunday you can calculate as per dayOfTheWeek.

Setting the year in Calendar [duplicate]

This question already has answers here:
java.util.Date is generating a wrong date?
(3 answers)
Closed 6 years ago.
I have the following piece of code.
SimpleDateFormat dateFormat = new SimpleDateFormat("dd/MM/YYYY HH:mm");
Calendar cal = Calendar.getInstance();
cal.clear();
cal.set(Calendar.YEAR, 2016);
cal.set(Calendar.MONTH, 11);
cal.set(Calendar.DAY_OF_MONTH, 31);
cal.set(Calendar.HOUR_OF_DAY, 22);
Date start = cal.getTime();
System.out.println(dateFormat.format(start));
cal.set(Calendar.YEAR, 2017);
cal.set(Calendar.MONTH, 0);
cal.set(Calendar.DAY_OF_MONTH, 1);
cal.set(Calendar.HOUR_OF_DAY, 5);
Date end = cal.getTime();
System.out.println(dateFormat.format(end));
It prints:
31/12/2016 22:00
01/01/2016 05:00
I expect that the year of the second date is 2017. What is going on? I'm using Java 1.7.

The correct date format should be dd/MM/yyyy HH:mm, not dd/MM/YYYY HH:mm, note the lower case y.
With that it works correctly.
From the docs:
y Year
Y Week year
Explanation of the difference between year and week year (from here):
A week year is a year where all the weeks in the year are whole weeks.
[...] Basically, this guarantees that a program working on a week's
data will not transition between years. [...] this also means that the beginning of the year may not start on the first of January.

This is working fine with the following dataFormat.
SimpleDateFormat dateFormat = new SimpleDateFormat("MM/dd/yyyy hh:mm");

Error getting month while using Calendar object

I'm using Calendar API to manipulate date. Here is snippet of code i'm trying.
Date date=new SimpleDateFormat("dd/mm/yyyy").parse("05/10/2013");
Calendar cal=Calendar.getInstance();
cal.setTime(date);
int month=cal.get(Calendar.MONTH);
Here i should get month as 9(Oct) but its returning 0(Jan).Even if I change date it still returns 0(Jan).
Why this is happening? Please help me.

use MM instead of mm small m gives Minute in hour and to get Month use capital M
Date date=new SimpleDateFormat("dd/MM/yyyy").parse("05/10/2013");
Calendar cal=Calendar.getInstance();
cal.setTime(date);
int month=cal.get(Calendar.MONTH);
System.out.println("" + month);
Output:
9
Java Docs

sue MM instead of mm in the given date format. M specifies month while m specifies minute according to java doc.
Date date=new SimpleDateFormat("dd/MM/yyyy").parse("05/10/2013")
Calendar cal=Calendar.getInstance();
cal.setTime(date);
int month=cal.get(Calendar.MONTH); // add +1 for correct month(10) otherwise it will be 9

How to get last month/year in java?

How do I find out the last month and its year in Java?
e.g. If today is Oct. 10 2012, the result should be Month = 9 and Year = 2012. If today is Jan. 10 2013, the result should be Month = 12 and Year = 2012.

Your solution is here but instead of addition you need to use subtraction
c.add(Calendar.MONTH, -1);
Then you can call getter on the Calendar to acquire proper fields
int month = c.get(Calendar.MONTH) + 1; // beware of month indexing from zero
int year = c.get(Calendar.YEAR);

java.time
Using java.time framework built into Java 8:
import java.time.LocalDate;
LocalDate now = LocalDate.now(); // 2015-11-24
LocalDate earlier = now.minusMonths(1); // 2015-10-24
earlier.getMonth(); // java.time.Month = OCTOBER
earlier.getMonth.getValue(); // 10
earlier.getYear(); // 2015

Use Joda Time Library. It is very easy to handle date, time, calender and locale with it and it will be integrated to java in version 8.
DateTime#minusMonths method would help you get previous month.
DateTime month = new DateTime().minusMonths (1);

you can use the Calendar class to do so:
SimpleDateFormat format = new SimpleDateFormat("yyyy.MM.dd HH:mm");
Calendar cal = Calendar.getInstance();
cal.add(Calendar.MONTH, -1);
System.out.println(format.format(cal.getTime()));
This prints : 2012.09.10 11:01 for actual date 2012.10.10 11:01

The simplest & least error prone approach is... Use Calendar's roll() method. Like this:
c.roll(Calendar.MONTH, false);
the roll method takes a boolean, which basically means roll the month up(true) or down(false)?

YearMonth class
You can use the java.time.YearMonth class, and its minusMonths method.
YearMonth lastMonth = YearMonth.now().minusMonths(1);
Calling toString gives you output in standard ISO 8601 format: yyyy-mm
You can access the parts, the year and the month. You may choose to use the Month enum object, or a mere int value 1-12 for the month.
int year = lastMonth.getYear() ;
int month = lastMonth.getMonthValue() ;
Month monthEnum = lastMonth.getMonth() ;

private static String getPreviousMonthDate(Date date){
final SimpleDateFormat format = new SimpleDateFormat("dd-MM-yyyy");
Calendar cal = Calendar.getInstance();
cal.setTime(date);
cal.set(Calendar.DAY_OF_MONTH, 1);
cal.add(Calendar.DATE, -1);
Date preMonthDate = cal.getTime();
return format.format(preMonthDate);
}
private static String getPreToPreMonthDate(Date date){
final SimpleDateFormat format = new SimpleDateFormat("dd-MM-yyyy");
Calendar cal = Calendar.getInstance();
cal.setTime(date);
cal.add(Calendar.MONTH, -1);
cal.set(Calendar.DAY_OF_MONTH,1);
cal.add(Calendar.DATE, -1);
Date preToPreMonthDate = cal.getTime();
return format.format(preToPreMonthDate);
}

You need to be aware that month is zero based so when you do the getMonth you will need to add 1. In the example below we have to add 1 to Januaray as 1 and not 0
Calendar c = Calendar.getInstance();
c.set(2011, 2, 1);
c.add(Calendar.MONTH, -1);
int month = c.get(Calendar.MONTH) + 1;
assertEquals(1, month);

You get by using the LocalDate class.
For Example:
To get last month date:
LocalDate.now().minusMonths(1);
To get starting date of last month
LocalDate.now().minusMonths(1).with(TemporalAdjusters.firstDayOfMonth());
Similarly for Year:
To get last year date:
LocalDate.now().minusYears(1);
To get starting date of last year :
LocalDate.now().minusYears(1).with(TemporalAdjusters.lastDayOfYear());

Here's the code snippet.I think it works.
Calendar cal = Calendar.getInstance();
SimpleDateFormat simpleMonth=new SimpleDateFormat("MMMM YYYY");
cal.add(Calendar.MONTH, -1);
System.out.println(simpleMonth.format(prevcal.getTime()));

Error while constructing date

I have such code:
Log.d(TAG, "day=%d, month=%d, year=%s", day, month, year);
Calendar c = Calendar.getInstance();
c.clear();
c.set(Calendar.YEAR, year);
c.set(Calendar.MONTH, month);
c.set(Calendar.DAY_OF_MONTH, day);
Log.i(TAG, "Date is parsed to %tF", c.getTime(), c.get(Calendar.DAY_OF_MONTH));
And this is log I get when executing:
day=11, month=11, year=1985
Date is parsed to 1985-12-10
Why not 1985-12-11? It works correct for some dates or in debug mode. But why it is not always working?
I also have similar issues when working with Date and when parsing dates from String via SimpleDateFormat
EDIT: Other examples of this code executing:
day=1, month=0, year=2012
Date is parsed to 2012-01-01
day=25, month=11, year=2011
Date is parsed to 2011-12-25
day=4, month=10, year=1979
Date is parsed to 1979-11-03
day=3, month=11, year=1984
Date is parsed to 1984-12-02
day, month and year can't be changed from other threads.

The month in Calendar is zero based. See here: http://docs.oracle.com/javase/6/docs/api/java/util/Calendar.html#MONTH
I suggest you read this: http://mindprod.com/jgloss/gregoriancalendar.html
If you can, it's actually easier and less bug prone to use joda-time - it has a much neater and safer API.

Month is 0-11 and day starts with 1.
Month
http://docs.oracle.com/javase/6/docs/api/java/util/Calendar.html#MONTH
Day
http://docs.oracle.com/javase/6/docs/api/java/util/Calendar.html#DAY_OF_MONTH
Edit:
Calendar c = Calendar.getInstance();
c.clear();
c.set(Calendar.YEAR, 1985);
c.set(Calendar.MONTH, 11);
c.set(Calendar.DAY_OF_MONTH, 11);
SimpleDateFormat sdf = new SimpleDateFormat("MM/dd/yyyy");
String strdate = sdf.format(c.getTime());
System.out.println(strdate);
Output:
12/11/1985

Try this:
Calendar c = Calendar.getInstance();
c.set(Calendar.YEAR, year);
c.set(Calendar.MONTH, month);
c.set(Calendar.DAY_OF_MONTH, day);
SimpleDateFormat simpleDateFormat =
new SimpleDateFormat("MM-dd-yyyy");
Log.v("the date is:", simepleDateFormat.format(c.getTime());

Thanks for the help. It seems to be some Android devices issue. It has appeared in 3 of 5 devices. I have fixed it by specifying time.
c.set(Calendar.HOUR_OF_DAY, 12);
c.set(Calendar.MINUTE, 30);