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SimpleDateFormat results in incorrect time

I have the following code
protected void amethod1() {
String strDate = "Thu May 18 16:24:59 UTC 2017";
String dateFormatStr = "EEE MMM dd HH:mm:ss zzz yyyy";
DateFormat dateFormat = new SimpleDateFormat(dateFormatStr);
Date formattedDate = null;
try {
formattedDate = dateFormat.parse(strDate);
} catch (ParseException e) {
e.printStackTrace();
}
}
The resulting value of formattedDate is- "Thu May 18 11:24:59 CDT 2017" .
I am testing this code in Chicago and the local timezone is CDT.
I am not able to understand why the time value changes from 16:24:59 to 11:24:59 even though. Am I missing something in the defined format of the date?

Class Date doesn't contain any timezone at all. It's just a number of milliseconds since 01.01.1970 00:00:00 GMT. If you try to see, what formattedDate contains with System.out.println or debugger, you'll get formatted date for your local timezone. 11:24:59 CDT and 16:24:59 UTC are the same time, so result is correct.
Is java.util.Date using TimeZone?
It is better to use jodatime or Java 8 Time API in order to better manage time and timezones.

First, you are getting the correct time. When Daylight Savings Time is in use in Chicago (which it is on May 18), the time is 11:24:59 when it’s 16:24:59 in UTC. So your Date value represents the same point in time. This is all you can expect from a Date.
I understand that you want not just a point in time, but also the UTC time zone. Since Axel P has already recommended Java 8 date and time API, I just wanted to fill in the details:
DateTimeFormatter parseFormatter = DateTimeFormatter.ofPattern(dateFormatStr, Locale.US);
ZonedDateTime dateTime = ZonedDateTime.parse(strDate, parseFormatter);
The result is
2017-05-18T16:24:59Z[UTC]
If you always want the UTC time zone, the Instant class is just right for it, so you will probably want to convert to it:
Instant instant = dateTime.toInstant();
Instants are always in UTC, popularly speaking.

SimpleDateFormat myFmt=new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
Date now=new Date();
System.out.println(myFmt.format(now));
I hope I can help you. If you can,please adopt.Thank you

The resulting value of formattedDate is- "Thu May 18 11:24:59 CDT 2017" . Why? because your time zone running -5 hour from UTC time you will find in below link wiki time zone abbreviations, if you want result in same timezone you need to specify timezone in formater Hope you get my concern
https://en.wikipedia.org/wiki/List_of_time_zone_abbreviations
public static void amethod1() {
String strDate = "Thu May 18 16:24:59 UTC 2017";
String dateFormatStr = "EEE MMM dd HH:mm:ss zzz yyyy";
SimpleDateFormat dateFormat = new SimpleDateFormat(dateFormatStr);
dateFormat.setTimeZone(TimeZone.getTimeZone("UTC"));
Date formattedDate = null;
try {
formattedDate = dateFormat.parse(strDate);
} catch (ParseException e) {
e.printStackTrace();
}
System.out.println("formattedDate: "+dateFormat.format(formattedDate));
}

You specified timezone, that's why after parsing time on current timezone (where you are), SimpleDateFormat sets UTC timezone. When you try to output your date, it is displayed on your current timezone

It appears you would need to specify the TimeZone as well when you format the Date For eg. .TimeZone.setDefault(TimeZone.getTimeZone("PST"));
Have a look at this discussion TimeZone

The output of a Date depends on the format specified, where you can specify the timezone, as shown in the example below:
protected void amethod2() {
String strDate = "Thu May 18 16:24:59 UTC 2017";
String dateFormatStr = "EEE MMM dd HH:mm:ss zzz yyyy";
DateFormat dateFormat = new SimpleDateFormat(dateFormatStr);
Date formattedDate = null;
try {
formattedDate = dateFormat.parse(strDate);
} catch (ParseException e) {
e.printStackTrace();
}
System.out.println("Date: " + formattedDate);
// Thu May 18 17:24:59 BST 2017, BST is my system default timezone
// Set the time zone to UTC for the calendar of dateFormat
dateFormat.setTimeZone(TimeZone.getTimeZone("UTC"));
System.out.println("Date in timezone UTC: " + dateFormat.format(formattedDate));
// Thu May 18 16:24:59 UTC 2017
// Set the time zone to America/Chicago
dateFormat.setTimeZone(TimeZone.getTimeZone("America/Chicago"));
System.out.println("Date in timezone America/Chicago: " + dateFormat.format(formattedDate));
// Thu May 18 11:24:59 CDT 2017
}
As for the IDs, such as "UTC" and "America/Chicago" in the example, you can get a complete list of them via TimeZone.getAvailableIDs(). You can print them out to have a look:
Arrays.stream(java.util.TimeZone.getAvailableIDs()).forEach(System.out::println);
And you'll have:
Africa/Abidjan
Africa/Accra
Africa/Addis_Ababa
Africa/Algiers
Africa/Asmara
Africa/Asmera
Africa/Bamako
Africa/Bangui
Africa/Banjul
Africa/Bissau
Africa/Blantyre
...

SimpleDateFormat parse not honouring timezone

public static void main(String[] args) throws ParseException {
SimpleDateFormat dt = new SimpleDateFormat("MM dd yy");
dt.setLenient(false);
dt.setTimeZone(TimeZone.getTimeZone("Asia/Hong_Kong"));
Date date = dt.parse("05 14 16");
System.out.println(date);
}
Output: Fri May 13 21:30:00 IST 2016
If i try to use the output it is switching to one day before instead of the correct day.
Is this expected or an issue with the API?

This is expected and there is no bug in Java.
Class Date does not contain timezone information. A java.util.Date is nothing more than wrapper for a number of milliseconds since 01-01-1970, 00:00:00 GMT. It does not remember that the string that it was parsed from contained information about a timezone.
When you display a Date, for example by (implicitly) calling toString() on it as you are doing here:
System.out.println(date);
it will be printed in the default timezone of your system, which is IST in your case.
If you want to print it in a certain timezone, then format it using a SimpleDateFormat object, setting the desired timezone on the SimpleDateFormat object. For example:
DateFormat df = new SimpleDateFormat("dd-MM-yyyy HH:mm:ss Z");
df..setTimeZone(TimeZone.getTimeZone("Asia/Hong_Kong"));
System.out.println(df.format(date));

SimpleDateFormat: unexpected results and unexpected parse exceptions

I'm having huge difficulties with simple date format. First of all, I know not all tutorials on all sites are actually good, but the fact that all non trivial formats (not dd/MM/yyyy) gave a parse exception (plus my own tests don't work as expected) is rather frustrating to me.
This is the site in question: http://www.mkyong.com/java/how-to-convert-string-to-date-java/
And I don't understand why something as simple as:
private static void unexpectedFailure() {
SimpleDateFormat formatter = new SimpleDateFormat("dd-MMM-yyyy");
String dateInString = "7-Jun-2013";
try {
Date date = formatter.parse(dateInString);
System.out.println(date);
System.out.println(formatter.format(date));
} catch (ParseException e) {
e.printStackTrace();
}
}
Throws a parse exception.
Also besides that, I'm trying to parse my own dates. This code gives strange results (unexpected I would say):
public static void doSomething(List<String> list) {
Iterator<String> iter = list.iterator();
String[] line = iter.next().split(" ");
System.out.println(Arrays.toString(line));
DateFormat format = new SimpleDateFormat("dd/MM/yyyy hh:mm:ss");
format.setLenient(true);
try {
System.out.println(line[0]+" "+line[1]);
System.out.println(format.parse(line[0]+" "+line[1]));
} catch (ParseException e) {
System.out.println("In theory this should not get caught.");
}
}
Prints out this:
[06/08/2015, 13:51:29:849, DEBUG, etc...]
06/08/2015 13:51:29:849
Thu Aug 06 13:51:29 EEST 2015
Thu Aug 06 13:51:29 EEST 2015 WHAT? WHY?
EDIT I'll try and explain. In my last code snippet I'm just trying to determine if the string is a date, and it passes "the test". However when I'm printing it out the format is simply bizzare. I'm starting to think that is because I'm printing a date. How can I even print a DateFormat? What I was expecting was dd/MM/yyyy hh:mm:ss not ddd MMM 06? hh:mm:ss G YYYY

And I don't understand why something as simple as:
(code snipped)
Throws a parse exception.
My guess is that it's tripping up over Jun which may not be a valid month abbreviation in your system default locale. I suggest you specify the locale in your SimpleDateFormat constructor:
SimpleDateFormat formatter = new SimpleDateFormat("dd-MMM-yyyy", Locale.US);
Then you're dealing with a locale which definitely has Jun as a month abbreviation.
That said, where possible I'd suggest using numeric formats where possibly, ideally ones following ISO-8601, e.g.
yyyy-MM-dd'T'HH:mm:ss
However when I'm printing it out the format is simply bizzare.
No it's not. You're effectively using
Date date = format.parse(line[0]+" "+line[1]);
System.out.println(date);
So that's calling Date.toString(), documented as:
Converts this Date object to a String of the form:
dow mon dd hh:mm:ss zzz yyyy
So that's working as expected. However, you want to format the date using your SimpleDateFormat - so you need to call format:
System.out.println(format.format(date));
Of course that just checks that it can round-trip, basically.
As a side note, I suspect you want HH (24-hour clock) instead of hh (12-hour clock) in your format string.

How to get Current Date using GMT in android?

I want Current Date in GMT wise Timezone.I used following code.
public static Date getGMTDate(String dateFormat) throws ParseException
{
SimpleDateFormat dateFormatGmt = new SimpleDateFormat(dateFormat);
dateFormatGmt.setTimeZone(TimeZone.getTimeZone("GMT"));
// Local time zone
SimpleDateFormat dateFormatLocal = new SimpleDateFormat(dateFormat);
// Time in GMT
return dateFormatLocal.parse(dateFormatGmt.format(new Date()));
}
//call above function.
SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
date = getGMTDate("yyyy-MM-dd HH:mm:ss");
when i will change my device date then time is display in GMT formate but Date is not display in GMT timezone.its display of device's date.
but I want Current GMT Date.

This may works
SimpleDateFormat dateFormatGmt = new SimpleDateFormat("dd:MM:yyyy HH:mm:ss");
dateFormatGmt.setTimeZone(TimeZone.getTimeZone("GMT"));
System.out.println(dateFormatGmt.format(new Date())+"");
Specify the format, and you will get it in GMT!
EDIT: You can also check This

I changed your method as below
public static String getGMTDate() {
DateFormat dateFmt = SimpleDateFormat.getDateTimeInstance(SimpleDateFormat.MEDIUM, SimpleDateFormat.MEDIUM);
dateFmt.setTimeZone(TimeZone.getTimeZone("GMT"));
// Time in GMT
return dateFmt.format(new Date());
}
And got the following date (which is same as what you wanted I believe)
07-18 10:41:54.525: D/test(6996): GMT Date is: **Jul 18, 2013 10:41:03 AM**
So simply call this method and it will return the GMT date in string format.
EDIT 1:
you are setting GMT time zone and not GMT Date. You are not trying to understand your code. When you called new Data() it returned your device date, and then you formatted it for the corresponding GMT date and time. So if your change your device date to 16th July then your code (or even my code) will return the GMT equivalent of 16th July time. If you want 18th July GMT time even when your device's date is 16th July 2000, then I don't think you can do it without getting it from some network entity.
EDIT 2:
You should look at this SO reference to a similar kind of problem and it may serve you well.

Output: 2016-08-01 14:37:48 UTC
final SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss z");
dateFormat.setTimeZone(TimeZone.getTimeZone("UTC"));
Works fine.

Exception in parsing date format [duplicate]

This question already has answers here:
Date Format JAVA
(5 answers)
Closed 9 years ago.
I have a date in the following format
//input date
Thu Jun 06 2013 00:00:00 GMT+0530 (India Standard Time)
//output date format
I want to change this to "dd-mm-yyyy, hh:mm:ss".
I get the input date format from db. I have to change that into output date format which i will be showing it in a grid.
I tried the following code.
DateFormat outputDate = new SimpleDateFormat("dd-mm-yyyy, hh:mm:ss");
try
{
Date date = outputDate.parse(facade.getDate.toString()); **//getting exception here**
outputDate = new SimpleDateFormat("dd-mm-yyyy, hh:mm:ss");
Date date1 = new SimpleDateFormat("dd-mm-yyyy, hh:mm:ss").parse(outputDate
.format(date));
facade.setDate(date1);
}catch (ParseException e)
{
// TODO Auto-generated catch block
e.printStackTrace();
}
I am getting
java.text.ParseException: Unparseable date: "2013-06-06 00:00:00.0".
Any help..

"2013-06-06 00:00:00.0" does not match "dd-mm-yyyy, hh:mm:ss" your format should be "dd-MM-yyyy hh:mm:ss" instead
But, looking at your code I'm guessing facade.getDate is actually a java.sql.Timestamp which inherits from java.util.Date so you can directly pass it to the format like so
new SimpleDateFormat("dd-MM-yyyy, hh:mm:ss").format(facade.getDate)

Here's some code which works for me:
import java.text.*;
import java.util.*;
public class Test {
public static void main(String[] args) throws Exception {
String input = "Thu Jun 06 2013 00:00:00 GMT+0530 (India Standard Time)";
DateFormat inputFormat = new SimpleDateFormat("E MMM dd yyyy HH:mm:ss 'GMT'z",
Locale.ENGLISH);
Date date = inputFormat.parse(input);
DateFormat outputFormat = new SimpleDateFormat("dd-MM-yyyy HH:mm:ss",
Locale.ENGLISH);
outputFormat.setTimeZone(TimeZone.getTimeZone("UTC"));
String output = outputFormat.format(date);
System.out.println(output);
}
}
Things to consider:
You need to work out your output time zone. Currently I've got it set to UTC, but that may not be what you want.
You really need to take a step back and think things through. You've clearly got two different formats - you're trying to convert from one to the other. So creating three different SimpleDateFormat objects all with the same format is never going to work.
You need to read documentation carefully... in SimpleDateFormat, M means month and m means minute; h uses the 12-hour clock and H uses the 24-hour clock.
This is assuming you actually need to start with a string though. If getDate is already a Date or a Timestamp, you can ignore the first part - just use the output part of the above code. You should avoid unnecessary string conversions wherever possible.
Note that dd-MM-yyyy is a slightly unusual format - are you sure you don't actually want yyyy-MM-dd which is more common (and sortable)?

DateFormat outputDate = new SimpleDateFormat("yyyy-dd-mm hh:mm:ss");
try {
Date date = outputDate.parse("2013-06-06 00:00:00.0");
System.out.println(new SimpleDateFormat("dd-mm-yyyy, hh:mm:ss").format(date));
} catch (ParseException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
works well, line 1 was incorrect. Your SimpleDateFormat.parse needs to be in the exact format of the input date. Then you want to output it in a different format so you make another one and set the format then call SimpleDateFormat.format(date) and I put a println on it.

Fault is here
DateFormat outputDate = new SimpleDateFormat("dd-mm-yyyy, hh:mm:ss");
pattern should be equals to Thu Jun 06 2013 00:00:00 GMT+0530 (India Standard Time). not to your out put strings pattern.

#Test
public void test() throws ParseException {
SimpleDateFormat sdf_org = new SimpleDateFormat("E MMM dd yyyy HH:mm:ss 'GMT'Z", Locale.ENGLISH);
Date d = sdf_org.parse("Thu Jun 06 2013 00:00:00 GMT+0530");
SimpleDateFormat sdf_target = new SimpleDateFormat("yyyy-mm-dd HH:mm:ss.SSS");
System.out.println(sdf_target.format(d));
}
output console : 2013-30-06 03:30:00.000