I am a little confused with the unix time stamp conversion to java.util.Date involving the time zones.
I have a unix time stamp that is "1367832568". it is a UTC date (Mon May 06 17:29:28 GMT+00:00 2013). when i do following :
Date d = new Date(1367832568 * 1000);
it gives me Mon May 06 17:29:28 GMT+08:00 2013 which is not correct. it should give me:
Mon May 07 01:29:28 GMT+08:00 2013
because the unix time stamp is actually a UTC date. so this is confusing. what should i do to convert the UTC unix time stamp to correctly convert to a UTC Date object.
I'm not sure exactely how are you formatting your date object, but by setting the timezone to the dateformat object (to GMT) I'm able to get
Mon May 06 09:29:28 GMT 2013 AM
which is the same date you are looking for.
long time = 1367832568 * (long) 1000;
Date date = new Date(time);
SimpleDateFormat format = new SimpleDateFormat("EEE MMM dd HH:mm:ss zzz yyyy a");
format.setTimeZone(TimeZone.getTimeZone("GMT"));
Log.d("date", format.format(date));
Related
I am working with expiration date of card. I have a API where I will get expiration date in "yyMM" format as "String". Here I am trying to use
SimpleDateFormat with TimeZone.getTimeZone("UTC")
So my code is like
String a= "2011";
SimpleDateFormat formatter = new SimpleDateFormat("yyMM");
formatter.setTimeZone(TimeZone.getTimeZone("UTC"));
Date date = formatter.parse(a);
System.out.println(date);
Now problem is, when I am passing 2011 the out it gives is Sat Oct 31 17:00:00 PDT 2020
Here you can see I am passing 11 as month but it is converting it to Oct instead of Nov.
Why?
And what other options I can use to convert string with yyMM to Date with Timezone?
You should use the Java 8 YearMonth class.
String a = "2011";
DateTimeFormatter inputFormat = DateTimeFormatter.ofPattern("yyMM");
YearMonth yearMonth = YearMonth.parse(a, inputFormat);
DateTimeFormatter outputFormat = DateTimeFormatter.ofPattern("MMMM yyyy");
System.out.println(yearMonth.format(outputFormat));
Output
November 2020
You parsed it fine, but it's printed in PDT, your local timezone.
Sat Oct 31 17:00:00 PDT 2020
Well, Date doesn't track timezones. The Calendar class does, which is internal to the formatter. But still, default print behavior is current timezone.
If you logically convert this output back to UTC, and it will be November 1 since PDT is UTC-7.
Basically, use java.time classes. See additional information here How can I get the current date and time in UTC or GMT in Java?
I have followed this SO answer for datetime conversion of 8601.
I will cite an example straight from w3 :
1994-11-05T08:15:30-05:00 corresponds to November 5, 1994, 8:15:30 am, US Eastern Standard Time.
1994-11-05T13:15:30Z corresponds to the same instant.
And this is what I run in android
SimpleDateFormat sdfSource = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ssZZZZZ");
dateTime = sdfSource.parse("2014-03-06T11:30:00-05:00");
System.out.println(dateTime); //Thu Mar 06 18:30:00 EET 2014
Obviously .parse()'s output is the local aware datetime. There has been a conversion from EST(-05:00) to EET (+02:00) since now I am in this timezone. However I do not want this auto-convertion.
Is there a way to parse a datetime string inyyyy-MM-dd'T'HH:mm:ssZZZZZ format and display THAT timezone's datetime? Preferable output:
Thu Mar 06 11:30:00 EST 2014
The EST and my location is an example. It can be any other timezones as well.
Internally Date objects are in UTC and that's what they're parsed to.
You cannot retrieve the original timezone from the Date but you can attempt to retrieve it from the original ISO-8601 stamp, and use it when formatting.
When you convert it to a string with toString(), it uses your local settings to format the date. If you want a specific representation, use a formatter to format the output, e.g.
int rawTimeZoneOffsetMillis = ...; // retrieve from ISO-8601 stamp and convert to milliseconds
TimeZone tz = new SimpleTimeZone(rawTimeZoneOffsetMillis, "name");
DateFormat outputFormat = DateFormat.getDateTimeInstance();
outputFormat.setTimeZone(tz);
System.out.println(df.format(dateTime));
ISO-8601 timestamps are not completely parseable with SimpleDateFormat. This answer has some code to work around some of the limitations.
Use sdfSource.setTimeZone() method
SimpleDateFormat sdfSource = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ssZZZZZ");
sdfSource.setTimeZone(TimeZone.getTimeZone("EST")); //give the timezone you want
dateTime = sdfSource.parse("2014-03-06T11:30:00-05:00");
System.out.println(dateTime); //Thu Mar 06 18:30:00 EET 2014
This should do fine.
Although you should not be worried while parsing the date as it is parsed to correct value can be displayed in any format or timezone you want.
SimpleDateFormat sdfSource = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ssZZZZZ");
sdfSource.setTimeZone( TimeZone.getTimeZone( "EST" ) );
dateTime = sdfSource.parse("2014-03-06T11:30:00-05:00");
System.out.println(sdfSource.format(dateTime)); //Thu Mar 06 18:30:00 EET 2014
I have the two Date objects which I am trying to format from being in MM/DD/YYYY format to "yyyy-mm-dd HH:mm:ss" format.
The current approach I am using is to first format those dates using SimpleDateFormat which will return two Strings, then I have to convert this string back to Date to get the formatted final Date objects.
So I was wondering if there was a simpler way to change the Date object format without going in many steps?
Thanks
The format is irrelevant. Date simply represents the number of milliseconds since the Unix epoch.
Remember, Date has no concept of format, it doesn't care.
You should simply format the Date object with whatever formatters you need...
For example...
Date date = new Date();
System.out.println(date);
System.out.println(DateFormat.getDateTimeInstance().format(date));
System.out.println(new SimpleDateFormat("dd/MM/yyyy").format(date));
System.out.println(new SimpleDateFormat("yyyy MMMM EE").format(date));
System.out.println(new SimpleDateFormat("EEEE MMMM yyyy").format(date));
System.out.println(date);
Outputs...
Wed Jan 22 11:55:18 EST 2014
22/01/2014 11:55:18 AM
22/01/2014
2014 January Wed
Wednesday January 2014
Wed Jan 22 11:55:18 EST 2014
Note how the first and last values don't change. Date has no internal concept of format, that's the responsibility of the formatter.
For example, if I took the String value 22/01/2014 and parsed it back to a Date using SimpleDateFormat
Date date = new SimpleDateFormat("dd/MM/yyyy").parse("22/01/2014");
And then outputted the date value...
System.out.println(date);
It would output something like...
Wed Jan 22 00:00:00 EST 2014
The format has being lost. It would need to use an appropriate formatter to change what is displayed
I am having a problem with formating a date using Java. The date formatter seems to parse my string using BST (British Summer Time) and not GMT+0 as defined by +0000 in the dateStr string in the code below.
String dateStr = "Tue Oct 02 01:06:00 +0000 2012";
DateFormat df = new SimpleDateFormat("EEE MMM dd HH:mm:ss Z yyyy");
Date date = df.parse(dateStr);
// Test the date
System.out.println(date.toString());
When I run the above code I get:
Tue Oct 02 02:06:00 BST 2012
Which is evidently not what I want. A useful point of information might be that when I run the following:
System.out.println(TimeZone.getDefault().getDisplayName());
I get:
Greenwich Mean Time
The output I'm trying to get is
Tue Oct 02 01:06:00 GMT 2012
I've already tried .setTimeZone on df but to no avail.
Note that Tue Oct 02 02:06:00 BST 2012 is the same time as Tue Oct 02 01:06:00 +0000 2012, just expressed in a different time zone. java.util.Date doesn't really deal with time zones, so as far as its concerned, there is no difference. The Date object you've constructed represents the correct date and time you want.
The Date.toString() method is essentially just a formatter that uses your JRE default TimeZone in its formatting. If you want to test that the Date object is correct, then you should build a java.util.Date object (using java.util.Calendar - most of the Date constructors have been deprecated) to test against. If you want to create a display string, then you should use the SimpleDateFormatter instance you've already created to format the Date object.
If you do need an object that stores TimeZone information, then you should use java.util.Calendar. java.util.Date is almost deprecated to the point of being unusable anyway. Or, do the same as I am and wait for the new Data and Time API coming out in Java 8.
The .toString() method is using your locale when printing the date.
Use:
SimpleDateFormat format = new SimpleDateFormat("EEE MMM dd HH:mm:ss Z yyyy");
format.setTimeZone(TimeZone.getTimeZone("GMT"));
System.out.println(format.format(date));
I understand that BST is already deprecated in SE 7.
you can try like here:
DateFormat df = new SimpleDateFormat("EEE MMM dd HH:mm:ss Z yyyy",
Locale.CANADA);
add Local args to SimpleDateFormat constructor
I have a UI where user can enter date. Now this date is converted to UTC format in my code which is inside an EJB.
My Query is if the browser in IST and my code is deployed in an server which in EST.
Now to convert to UTC from which timezone I need to convert the date from IST or ETC.
My code is like:
User enters a date in DatePicker. The value of DatePicker is assigned to plain Java Date Object.
You need to do IST to UTC
Your user is selecting date assuming it is IST. So in your server code you need to consider the user time zone before creating a Date object which will be in server time zone. Since server is in EST you need to convert it again to UTC before storing.
Most of the servers have time configured at UTC time zone, so only one conversion is all that is needed in that case.
When you get a Date its in the local time zone.
private static final DateFormat FULL_RFC822_DATETIME_FORMAT = new SimpleDateFormat("EEE, d MMM yyyy HH:mm:ss", Locale.US);
public static void date2() throws Exception {
FULL_RFC822_DATETIME_FORMAT.setTimeZone(new SimpleTimeZone(0, "GMT")); //frozen
Date d = new Date(); // in local time zone
System.out.println(d);
System.out.println(FULL_RFC822_DATETIME_FORMAT.format(d) + " GMT");
}
I get
Fri Dec 07 11:15:58 CET 2012
Fri, 7 Dec 2012 10:15:58 GMT
GMT + UTC are the same.