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Gettting date in dd/mm/yyyy format using Horizontal-Calendar library (Mulham-Raee/Horizontal-Calendar) calendar

I am looking to get date in dd/mm/yyyy format using Horizontal-calendar (Mulham-Raee library). I get corrent day and year but I cannot figure out to get correct month. My code is :
//define your start and end dates to set the range of the calendar:
/* starts before 1 month from now */
Calendar startDate = Calendar.getInstance();
startDate.add(Calendar.MONTH, -1);
final HorizontalCalendar horizontalCalendar;
/* ends after 1 month from now */
Calendar endDate = Calendar.getInstance();
endDate.add(Calendar.MONTH, 1);
//Then setup HorizontalCalendar in your Activity through its Builder:
horizontalCalendar = new HorizontalCalendar.Builder(this, R.id.calendarView)
.range(startDate, endDate)
.datesNumberOnScreen(5)
.build();
horizontalCalendar.setCalendarListener(new HorizontalCalendarListener() {
#Override
public void onDateSelected(Calendar date, int position) {
//do something
Calendar cal = horizontalCalendar.getDateAt(position);
cal.add(Calendar.DATE,1);
SimpleDateFormat format1 = new SimpleDateFormat("dd/mm/yyyy");
String formatted = format1.format(cal.getTime());
Log.d("Selected Date", formatted);
}
});

You have used the small letter 'mm for parsing month. Please use capital 'MM'
new SimpleDateFormat("dd/MM/yyyy");
You can find more about parsing pattern here

use this format dd/MM/yyyy intead of dd/mm/yyyy.Let me know if it's works for you.

How can I check if date is before a specific time?

I have to check, if a date variable is before a specific time. The variable has the format dd.MM.yyyy HH:mm:ss.
Let's take todays date 31.10.2016 15:20:45. The value of the variable is 30.10.2016 14:00:21. How can I check now if the variable is one day older than today and if the time is before or equals 23:00?
I tried following code.
Date today = new Date();
Calendar c = Calendar.getInstance();
c.setTime(causedAt);
c.add(Calendar.DATE, 1);
if (c.getTime().compareTo(today) < 0) { // It's more than 1 day.
setOneDayOverdue(true);
setFiveDaysOverdue(false);
}
But with this code the part with the time is missing.
The solution should work with Java 7 and without any external libraries like Joda-Time.

You should use the new Java 8 Date / Time API:
LocalDateTime NOW = LocalDateTime.now(); // e.g. 31.10.2016 15:20:45
// parse given Date/Time
LocalDateTime input = LocalDateTime.parse(strInput, DateTimeFormatter.ofPattern("dd.MM.yyyy HH:mm:ss"));
// Check if input is before "now"
boolean isBefore = input.isBefore(NOW);
See https://docs.oracle.com/javase/8/docs/api/java/time/LocalDateTime.html to get all the methods you need to meet your requirements. For example:
LocalDateTime yesterday = NOW.minusDays(1);
boolean isBeforeYesterday = input.isBefore(yesterday);
With getHour() and getMinute() you can check for <= 23:00. Or you can use LocalTime but it seems getting those two fields should be enough for you.

So I got following code that works for me:
public void setOverdueFlagIfRequired(Date today, Date causedAtDate) {
Calendar now = Calendar.getInstance();
now.setTime(today);
Calendar causedAt = Calendar.getInstance();
causedAt.setTime(causedAtDate);
Calendar yesterday2300 = Calendar.getInstance();
yesterday2300.setTime(today);
yesterday2300.add(Calendar.DATE, -1);
yesterday2300.set(Calendar.HOUR_OF_DAY, 23);
yesterday2300.set(Calendar.MINUTE, 0);
yesterday2300.set(Calendar.SECOND, 0);
yesterday2300.set(Calendar.MILLISECOND, 0);
Calendar fiveDaysBack2300 = Calendar.getInstance();
fiveDaysBack2300.setTime(yesterday2300.getTime());
fiveDaysBack2300.add(Calendar.DATE, -4);
if (causedAt.compareTo(fiveDaysBack2300)<=0) {
setFiveDaysOverdue(true);
}
else if (causedAt.compareTo(yesterday2300)<=0 && causedAt.compareTo(fiveDaysBack2300)>0) {
setOneDayOverdue(true);
}
}

How do I add 2 weeks to a Date in java? [duplicate]

This question already has answers here:
Modify the week in a Calendar
(4 answers)
Closed 5 years ago.
I am getting a Date from the object at the point of instantiation, and for the sake of outputting I need to add 2 weeks to that date. I am wondering how I would go about adding to it and also whether or not my syntax is correct currently.
Current Java:
private final DateFormat dateFormat = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss");
private Date dateOfOrder;
private void setDateOfOrder()
{
//Get current date time with Date()
dateOfOrder = new Date();
}
public Date getDateOfOrder()
{
return dateOfOrder;
}
Is this syntax correct? Also, I want to make a getter that returns an estimated shipping date, which is 14 days after the date of order, I'm not sure how to add and subtract from the current date.

Use Calendar and set the current time then user the add method of the calendar
try this:
int noOfDays = 14; //i.e two weeks
Calendar calendar = Calendar.getInstance();
calendar.setTime(dateOfOrder);
calendar.add(Calendar.DAY_OF_YEAR, noOfDays);
Date date = calendar.getTime();

I will show you how we can do it in Java 8. Here you go:
public class DemoDate {
public static void main(String[] args) {
LocalDate today = LocalDate.now();
System.out.println("Current date: " + today);
//add 2 week to the current date
LocalDate next2Week = today.plus(2, ChronoUnit.WEEKS);
System.out.println("Next week: " + next2Week);
}
}
The output:
Current date: 2016-08-15
Next week: 2016-08-29
Java 8 rocks !!

Use Calendar
Date date = ...
Calendar c = Calendar.getInstance();
c.setTime(date);
c.add(Calendar.WEEK_OF_MONTH, 2);
date = c.getTime();

Try this to add two weeks.
long date = System.currentTimeMillis() + 14 * 24 * 3600 * 1000;
Date newDate = new Date(date);

if pass 14 to this addDate method it will add 14 to the current date and return
public String addDate(int days) throws Exception {
final DateFormat dateFormat1 = new SimpleDateFormat(
"yyyy/MM/dd HH:mm:ss");
Calendar c = Calendar.getInstance();
c.setTime(new Date()); // Now use today date.
c.add(Calendar.DATE, addDays); // Adding 5 days
return dateFormat1.format(c.getTime());
}

Using the Joda-Time library will be easier and will handle Daylight Saving Time, other anomalies, and time zones.
java.util.Date date = new DateTime( DateTimeZone.forID( "America/Denver" ) ).plusWeeks( 2 ).withTimeAtStartOfDay().toDate();

If you are on java 8 you can use new date time api http://docs.oracle.com/javase/8/docs/api/java/time/LocalDateTime.html#plusWeeks-long-
if you are on java 7 or more old version of java you should use old api http://docs.oracle.com/javase/8/docs/api/java/util/Calendar.html#add-int-int-

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()));

Java Calendar: calculate start date and end date of the previous week

What is most convenient and shortest way to get start and end dates of the previous week?
Example: today is 2011-10-12 (input data),but I want to get 2011-10-03 (Monday's date of previous week) and 2011-10-09 (Sunday's date of previous week).

Here's another JodaTime solution. Since you seem to want Dates only (not timestamps), I'd use the DateMidnight class:
final DateTime input = new DateTime();
System.out.println(input);
final DateMidnight startOfLastWeek =
new DateMidnight(input.minusWeeks(1).withDayOfWeek(DateTimeConstants.MONDAY));
System.out.println(startOfLastWeek);
final DateMidnight endOfLastWeek = startOfLastWeek.plusDays(6);
System.out.println(endOfLastWeek);
Output:
2011-10-12T18:13:50.865+02:00
2011-10-03T00:00:00.000+02:00
2011-10-10T00:00:00.000+02:00

public static Calendar firstDayOfLastWeek(Calendar c) {
c = (Calendar) c.clone();
// last week
c.add(Calendar.WEEK_OF_YEAR, -1);
// first day
c.set(Calendar.DAY_OF_WEEK, c.getFirstDayOfWeek());
return c;
}
public static Calendar lastDayOfLastWeek(Calendar c) {
c = (Calendar) c.clone();
// first day of this week
c.set(Calendar.DAY_OF_WEEK, c.getFirstDayOfWeek());
// last day of previous week
c.add(Calendar.DAY_OF_MONTH, -1);
return c;
}

I would go for #maerics answer if third party library is not involved. I have to replace roll() method with add() method as roll will leave the higher field unchanged. e.g., 22nd August will be obtained from 1st August being rolled -7 days. Note the month remain unchanged.
The source code goes as below.
public static Calendar[] getLastWeekBounds(Calendar c) {
int cdow = c.get(Calendar.DAY_OF_WEEK);
Calendar lastMon = (Calendar) c.clone();
lastMon.add(Calendar.DATE, -7 - (cdow - Calendar.MONDAY));
Calendar lastSun = (Calendar) lastMon.clone();
lastSun.add(Calendar.DATE, 6);
return new Calendar[] { lastMon, lastSun };
}

You can use the Calendar.roll(int,int) method with arguments Calendar.DATE and an offset for the current day of week:
public static Calendar[] getLastWeekBounds(Calendar c) {
int cdow = c.get(Calendar.DAY_OF_WEEK);
Calendar lastMon = (Calendar) c.clone();
lastMon.roll(Calendar.DATE, -7 - (cdow - Calendar.MONDAY));
Calendar lastSun = (Calendar) lastMon.clone();
lastSun.roll(Calendar.DATE, 6);
return new Calendar[] { lastMon, lastSun };
}
This function returns an array of two Calendars, the first being last week's Monday and last week's Sunday.
Wow, the Java date APIs are terrible.

Calendar today = Calendar.getInstance();
Calendar lastWeekSunday = (today.get(Calendar.DAY_OF_WEEK) == Calendar.SUNDAY) ? today.roll(-7): today.roll(Calendar.DAY_OF_YEAR, Calendar.SUNDAY - today.get(Calendar.DAY_OF_WEEK));
Calendar lastWeekMonday = lastWeekSunday.roll( Calendar.DAY_OF_YEAR, -6 );

Using Joda:
DateTime input;
DateTime startOfLastWeek = input.minusWeeks(1).minusDays(input.getDayOfWeek()-1);
DateTime endOfLastWeek = input.minusWeeks(1).plusDays(input.getDayOfWeek()+1);
DateTime endOfLastWeek = startOfLastWeek.plusDays(6);
EDIT:
Joda does not allow a different first day of the week, but strictly sticks to the ISO standard, which states that a week always starts on Monday. However, if you need to make that configurable, you could pass the desired first day of the week as a parameter. See the above link for some other ideas.
public DateTime getFirstDayOfPreviousWeek(DateTime input)
{
return getFirstDayOfPreviousWeek(input, DateTimeConstants.MONDAY);
}
public DateTime getFirstDayOfPreviousWeek(DateTime input, int firstDayOfWeek)
{
return new DateTime(input.minusWeeks(1).withDayOfWeek(firstDayOfWeek));
}
public DateTime getLastDayOfPreviousWeek(DateTime input)
{
return getLastDayOfPreviousWeek(input, DateTimeConstants.MONDAY);
}
public DateTime getLastDayOfPreviousWeek(DateTime input, int firstDayOfWeek)
{
return new DateTime(getFirstDayOfPreviousWeek(input, firstDayOfWeek).plusDays(6));
}