Develop Reference

how to format string datetime in android [duplicate]

This question already has answers here:
Change date string format in android
(8 answers)
Date format conversion Android
(9 answers)
Closed 2 years ago.
I get datetime data from soap web service to get string:2020-05-03T00:00:00.
Is there a way to split the string into dd / mm / yyyy, and if it is null then omitted?
I am using a substring(0,10) , but it doesn't work very well.

You can do it this way.
Parse the input string.
LocalDateTime dateTime = LocalDateTime.parse("2020-05-03T00:00:00");
Generate text representing the value of that LocalDateTime object.
DateTimeFormatter formatter = DateTimeFormatter.ofPattern("dd/MM/yyyy");
String dateTimeString = dateTime.format(formatter);
System.out.println(dateTimeString);
03/05/2020
For early Android before 26, see the ThreeTenABP & ThreeTen-Backport projects, a back-port of most of the java.time functionality.

try with this
try {
SimpleDateFormat inputFormat = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss");
SimpleDateFormat outputFormat = new SimpleDateFormat("dd-MM-yyyy");
Date date = null;
date = inputFormat.parse("2020-05-03T00:00:00");
String formattedDate = outputFormat.format(date);
System.out.println("coverted: "+formattedDate);
} catch (ParseException e) {
e.printStackTrace();
}
Output: 03-05-2020

You can use java Calendar class to get Date, Month and Year as shown in below
String s = "2020-05-03T00:00:00";
Calendar calendar = new GregorianCalendar();
DateFormat format = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss");
Date dateObj = null;
try {
dateObj = format.parse(s);
calendar.setTime(dateObj);
int date = calendar.get(Calendar.DATE);
int month = calendar.get(Calendar.MONTH) + 1;// As start from 0
int year = calendar.get(Calendar.YEAR);
System.out.println("Formatted Date -> "+ date + "/" + month + "/" +year);
} catch (ParseException e) {
e.printStackTrace();
}
You can do many more thing after converting it to Calendar class object, like hour, minutes, day of week etc

Calculate no of days between two dates in java [duplicate]

This question already has answers here:
Android/Java - Date Difference in days
(18 answers)
Closed 6 years ago.
I need to calculate number of days between two dates and I am using below code. problem is it is returning me 2 but actually it should return 3 because difference between 30 june 2016 to 27 june is 3. can you please help where it should include current date as well in difference?
public static long getNoOfDaysBtwnDates(String expiryDate) {
SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd");
Date expDate = null;
long diff = 0;
long noOfDays = 0;
try {
expDate = formatter.parse(expiryDate);
//logger.info("Expiry Date is " + expDate);
// logger.info(formatter.format(expDate));
Date createdDate = new Date();
diff = expDate.getTime() - createdDate.getTime();
noOfDays = TimeUnit.DAYS.convert(diff, TimeUnit.MILLISECONDS);
long a = TimeUnit.DAYS.toDays(noOfDays);
// logger.info("No of Day after difference are - " + TimeUnit.DAYS.convert(diff, TimeUnit.MILLISECONDS));
System.out.println(a);
System.out.println(noOfDays);
} catch (ParseException e) {
e.printStackTrace();
}
return noOfDays;
}
expiry date is 2016-06-30 and current date is 2016-06-27

Reason is, you are not subtracting two dates with same time format.
Use Calendar class to change the time as 00:00:00 for both date and you will get exact difference in days.
Date createdDate = new Date();
Calendar time = Calendar.getInstance();
time.set(Calendar.HOUR_OF_DAY, 0);
time.set(Calendar.MINUTE, 0);
time.set(Calendar.SECOND, 0);
time.set(Calendar.MILLISECOND, 0);
createdDate = time.getTime();
More explaination in Jim Garrison' answer

Why not use LocalDate?
import java.time.LocalDate;
import static java.time.temporal.ChronoUnit.DAYS;
long diffInDays(LocalDate a, LocalDate b) {
return DAYS.between(a, b);
}

The problem is that
Date createdDate = new Date();
sets createdDate to the current instant, that is, it includes the current time as well as the date. When you parse a string using the given format, the time is initialized to 00:00:00.
Let's say you ran this at exactly 18:00 local time, you end up with
createdDate = 2016-06-27 18:00:00.000
expDate = 2016-06-30 00:00:00.000
The difference is 2 days 6 hours, not 3 days.
You should be using the newer java.time.* classes from Java 8. There is a class LocalDate that represents dates without time-of-day. It includes methods for parsing using a format, and LocalDate.now() to get the current date, as well as methods for calculating intervals between LocalDate instances.

Using the Calendar.get(Calendar.DAY_OF_MONTH) as pointed out by python:
SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd");
Date expDate = null;
String expiryDate ="2016-06-30";
int diff = 0;
try {
expDate = formatter.parse(expiryDate);
//logger.info("Expiry Date is " + expDate);
// logger.info(formatter.format(expDate));
Calendar cal = Calendar.getInstance();
int today = cal.get(Calendar.DAY_OF_MONTH);
cal.setTime(expDate);
diff = cal.get(Calendar.DAY_OF_MONTH)- today;
} catch (ParseException e) {
e.printStackTrace();
}
System.out.println(diff);

How do I take date as input and add +3 and set label with new date in java swings [duplicate]

This question already has answers here:
How can I increment a date by one day in Java?
(32 answers)
Closed 6 years ago.
How do I take date as input and add 3 in selected date then set label with updated date in java swings? My date format is YYYY-MM-DD.
eg if I enter 2016-04-04 then change date to 2016-04-07 and set a label to it.
i Tried this . . gives me wring output. 1970-03-01 is ouput
plz help

To use this code:
Declare the following variables:
String youdate = "2016-04-04";
Date mmdate;
TextView tv;
and use this code:
try {
mmdate = new SimpleDateFormat("yyyy-MM-dd").parse(youdate);
} catch (ParseException e) {
e.printStackTrace();
}
Calendar c = Calendar.getInstance();
c.setTime(mmdate);
c.add(Calendar.DATE, 3);
Date newdate = c.getTime();
SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd");
tv = (TextView)findViewById(R.id.tv);
tv.setText(format.format(newdate));
tv contains 2016-04-07

You can add 72 hours in date format to create new date with +3 days addition.
public String nextDate(String date) {
LocalDate parsedDate = LocalDate.parse(date);
LocalDate addedDate = parsedDate.plusDays(3);
DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy-MM-dd");
return addedDate.format(formatter);
}

I want my string to converted to a day [duplicate]

This question already has answers here:
How to determine day of week by passing specific date?
(28 answers)
Closed 7 years ago.
I have this string
String s = "29/04/2015"
And I want it to produce the name of that day in my language, which is Norwegian.
For example:
29/04/2015 is "Onsdag"
30/04/2015 is "Torsdag"
How can I do this?

String dateString = "29/04/2015";
DateFormat dateFormat = new SimpleDateFormat("MM/dd/yyyy");
Date date = dateFormat.parse(dateString);
SimpleDateFormat formatter = new SimpleDateFormat("E", Locale.no_NO);
String day = formatter.format(date);
Now day will have the day in given locale. Update

You need to configure an instance of DateFormat, with your locale, (take a look at https://docs.oracle.com/javase/7/docs/api/java/util/Locale.html).
then parse the Date and get the day, as Dilip already suggests.

You can use date parsing combined with Locale settings to get the desired output. For e.g. refer following code.
String dateStr = "29/04/2015";
SimpleDateFormat dtf = new SimpleDateFormat("dd/MM/yyyy");
Date dt = dtf.parse(dateStr);
Calendar cal = Calendar.getInstance();
cal.setTime(dt);
String m = cal.getDisplayName(Calendar.DAY_OF_WEEK, Calendar.LONG_FORMAT, new Locale("no", "NO"));
System.out.println(m);
For more information about locale, visit Oracle Java Documentation.

First you will need to parse the String to a Date. Then use a Calendar to get the day of the week. You can use an array to convert it to the appropriate string.
// Array of Days
final String[] DAYS = {
"søndag", "mandag", "tirsdag", "onsdag", "torsdag", "fredag", "lørdag"
};
// Parse the date
final String source = "27/04/2015";
final DateFormat format = new SimpleDateFormat("dd/MM/yyyy");
Date date = new Date();
try {
date = format.parse(source);
} catch (final ParseException e) {
e.printStackTrace();
}
// Convert to calendar
final Calendar c = Calendar.getInstance();
c.setTime(date);
final int dayOfWeek = c.get(Calendar.DAY_OF_WEEK);
// Get the day's name
System.out.println("Day of Week: " + dayOfWeek);
System.out.println("Day = " + DAYS[dayOfWeek - 1]);

You need to parse your text with date to Date instance and then format it back to text. You can do it with SimpleDateFormat class which supports many patterns of dates like
dd/MM/yyyy for your original date,
and EEEE for full name of day in month.
While formatting you will also need to specify locale you want to use. To create Norway specific locale you can use for instance
Locale nor = Locale.forLanguageTag("no-NO");
So your code can look more or less like:
String text = "29/04/2015";
Locale nor = Locale.forLanguageTag("no-NO");
SimpleDateFormat sdf = new SimpleDateFormat("dd/MM/yyyy", nor);
SimpleDateFormat dayOfWeek = new SimpleDateFormat("EEEE", nor);
Date date = sdf.parse(text);
System.out.println(dayOfWeek.format(date));
Output: onsdag.

final int SUNDAY = 1;
final int ONSDAG = 2;
final int TORSDAG = 3;
....
....
String s = "29/04/2015";
DateFormat dateFormat = new SimpleDateFormat("MM/dd/yyyy");
Date date = dateFormat.parse(s);
Calendar calendar = Calendar.getInstance();
calendar.setTime(date);
int day = calendar.get(Calendar.DAY_OF_WEEK);
String dayString;
switch (day) {
case(ONSDAG):
dayString = "ONSDAG";
break;
....
}
EDIT: I just tested this and it actually starts from Sunday, and returns the value of 1 for sunday, I've changed the constant values to reflect this.

First you'll need a Calendar object.
Calendar cal = Calendar.getInstance();
String s = "29/04/2015"
SimpleDateFormat format = new SimpleDateFormat("dd/MM/yyyy");
cal.setTime(format.parse(s));
From the Calendar you can get the day of the week.
int dayOfWeek = cal.get(Calendar.DAY_OF_WEEK);
dayOfWeek will be 1-7 with Sunday (in english) being 1

You can use an HashMap map where the first parametri is the date "29/4/2015" while the second is the meaning. You can use your string to get the meaning map.get (yourString).

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-