I am using SimpleDateFormat to get the current month but i want to show a recyclerview table with information of this month and past three months.
My php json loads this but i want to put automatically it in android.
periodo1 = findViewById(R.id.tittle_periodo1);
periodo2 = findViewById(R.id.tittle_periodo2);
periodo3 = findViewById(R.id.tittle_periodo3);
periodo4 = findViewById(R.id.tittle_periodo4);
SimpleDateFormat month_date = new SimpleDateFormat("yyyyMM");
String month1 = month_date.format(c.getTime());
periodo1.setText(month1);
try this :
Calendar calendar = Calendar.getInstance();
calendar.setTime(new Date());
calendar.add(Calendar.MONTH, -3); // -3 is Number of months past (july)
Date newDate = calendar.getTime();
and you can format it if you want :
String date = DateFormat.format("MM/dd/yyyy", newDate).toString();
With Java8 syntax you can use time library to achieve this
import java.time.LocalDate;
LocalDate now = LocalDate.now(); // 2019-11-01 (Nov)
LocalDate minusOneMonth = now.minusMonths(1); // 2019-10-01
minusOneMonth.getMonth().getValue(); // Gives -1 month (10)
LocalDate minusTwoMonth = now.minusMonths(2); // 2019-09-01
minusTwoMonth.getMonth().getValue(); // Gives -2 month (09)
Hope that's what you are looking for.
If you can't use Java8 syntax, use following
Calendar cal = Calendar.getInstance();
cal.setTime(new Date());
cal.add(Calendar.MONTH, -1);
Date newDate = cal.getTime();
.... = new SimpleDateFormat("M")
If the user selects 01:25 AM, how to get the corresponding epoch time for this hour for the next day?
I did something like that, which is pretty "face coded" :
private long returnEpochForThisHour(String hour){
DateFormat dateFormat = new SimpleDateFormat("yyyy/MM/dd HH:mm");
Date date = new Date();
String stringDate = dateFormat.format(date).substring(0, 10) + " " + hour;
Date newDate = new Date(stringDate);
Calendar c = Calendar.getInstance();
c.setTime(newDate);
c.add(Calendar.DATE, 1);
Date lastDate = c.getTime();
System.out.println(lastDate.getTime());
return lastDate.getTime();
}
When doing something like:
returnEpochForThisTime("01:25");
It returns:
1544491500000
But in Android devices it's not working properly. Is there a better way to do this?
Given a week_of_year, how can I get the dates for the start and end of the week?
Example:
Let's say the date is Jan/1/2017.
Calendar calendar = Calendar.getInstance();
// Let's assume that we've set calendar to Jan/1/2017.
Integer week_of_year = calendar.get(Calendar.WEEK_OF_YEAR)
week_of_year would return 1. Presumably, week 1 is anything between Jan/1/2017 to Jan/7/2017.
How can I reverse lookup week_of_year=1 and get the min/max of Jan/7/2017 to Jan/6/2017? or for any other valid week_of_year value.
SimpleDateFormat sdf = new SimpleDateFormat("dd-MM-yyyy");
Calendar cal = Calendar.getInstance();
cal.set(Calendar.WEEK_OF_YEAR, 1);
cal.set(Calendar.DAY_OF_WEEK, Calendar.SUNDAY);
System.out.println("Start Date: " + sdf.format(cal.getTime()));
cal.set(Calendar.DAY_OF_WEEK, Calendar.SATURDAY);
System.out.println("End Date: " + sdf.format(cal.getTime()));
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()));
How would I get the current day of the week?
Can some please help me?
Use a Calendar and get the DAY_OF_WEEK field:
Calendar cal = Calendar.getInstance();
int dayOfWeek = cal.get(Calendar.DAY_OF_WEEK);
Or if you want the day name instead, you can use SimpleDateFormat:
Date today = Calendar.getInstance().getTime();
DateFormat df = new SimpleDateFormat("EEEE", Locale.ENGLISH); // override the default Locale
String dayNameInWeek = df.format(today);
To get a text display of the day of the week you can use:
DateFormat dateFormat = new SimpleDateFormat("EEEE");
System.out.println("Today is " + dateFormat.format(new Date()));
output:
Today is Sunday