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How to get 2 date objects holding the current time, one in GMT and the other in local

I am trying to fill 2 date objects, one in Local time and the other in UTC.
I AM NOT TRYING TO PRINT THE DATE AS A STRING IN GMT/UTC, please do not suggest DateFormatting, and dont say its a duplicate until you read the full question.
Local, I have no problem:
Date dateLocal = new Date();
The problem is I cant get the utcDate to be UTC.
Using a Calendar like so:
TimeZone utcTimeZone = TimeZone.getTimeZone("UTC");
Calendar c = new GregorianCalendar();
c.setTime(new Date());
c.setTimeZone(TimeZone.getTimeZone(utcTimeZone.getID()));
Date utcDate = c.getTime();
When debugged or submitted to the webservice, utcDate shows in my local timezone, instead of UTC.
Using Joda:
DateTime utcDateTime = DateTime.now(DateTimeZone.UTC);
Date utcDate = utcDateTime.toDate();
Same issue, utcDate when debugged/submitted to webservice is showing in local time.
Here is how the object looks when debugged:
This is an issue because this causes the webservice (which i have no access to) to think this time is UTC, so when it does its work and conversions, the time is always off by 4 hours, since for me the UTC to Local conversion is GMT -4.
The ONLY way i have been able to get this to submit the date in UTC time is by adding:
TimeZone.setDefault(TimeZone.getTimeZone("UTC"));
BUT this also changes the LocalTime object, even though this object was defined and set before the default TimeZone was changed.
So i get it, the Date() object uses the JVM locale, so any time a Date is created, its created in the default timezone, and apparently whenever the default timezone is changed, all of the Date objects (even if they are already created) change to the new default timezone... I know Date objects are just the millis between now and 1970 whatever, but the TimeZone is obviously being taken into account in the Webservice and this is messing up my results...how can i get the dates the way i want?

Difference between 2 dates in days and in double

I am working on an app and i need to get the difference between the actual date and a date inserted by the user, in days and in double.
Any idea on how to make this? I've tried some things but without success.

First you must decide if you want to consider the time of the day and the timezone to calculate the difference, because this can lead to different results.
Example: current date (AKA "today") is April 17th or 18th, depending on where in the world you are. Actually, depending on the time of the day, there might be 3 different "todays" in the world, at the same time. What timezone are you using to calculate the difference?
the user will enter a date: only day, month and year? Will it enter the hours? Are you using the user's device's timezone or some specific zone?
the same questions apply to the current date
Depending on the choices you make, you might get a different result.
Anyway, I'd use this lib: http://www.threeten.org/threetenbp/
or java.time classes, if available in your API level. In both API's you can use the following.
To use a date (day-month-year only) and the device's default timezone, I'd choose the LocalDate class:
// current date in device's default timezone
LocalDate now = LocalDate.now();
// some date from input values (May 10th 2018)
LocalDate dt = LocalDate.of(2018, 5, 10);
// difference in days
long diff = ChronoUnit.DAYS.between(now, dt); // 23
If you want to consider the time of the day (hours, minutes, etc), use a LocalDateTime. But in this case, ChronoUnit.DAYS considers a day has passed when the time is >= the other (ex: the difference between April 17th at 10 AM and April 18th 9:59 AM is zero days, because the time of the day didn't reach 10 AM, so it didn't complete 1 day - with LocalDate this doesn't happen because this class doesn't have time-of-the-day fields and considers only the day, month and year).
If you want to consider everything (date, time, and timezone), including Daylight Saving Time transitions, use a ZonedDateTime instead (the code is very similar, the only difference is that you can choose a timezone to work with):
// current date/time in device's default timezone
ZonedDateTime now = ZonedDateTime.now(ZoneId.systemDefault());
// some date from input values (May 10th 2018, 10 AM in New York timezone)
ZonedDateTime dt = ZonedDateTime.of(2018, 5, 10, 10, 0, 0, 0, ZoneId.of("America/New_York"));
// difference in days
long diff = ChronoUnit.DAYS.between(now, dt); // 23
You can choose between the device's default timezone (ZoneId.systemDefault()) or a specific one (ZoneId.of("America/New_York")). You can check all the available timezones with ZoneId.getAvailableZoneIds().
Maybe it doesn't make sense to use current date in one timezone and user's date in another (I'd use the same for both), but that's up to you to decide.

Calendar c = Calendar.getInstance();
Calendar c2 // = what you will get from the user
long diff = c.getTimeInMillis()-c2.
double days = (double) diff/(1000*60*60*24);
that is what i have in mind.
I hope this helps

use this way
public static double getTimeDiffBetweenDate(Date startDateTime, Date finishDateTime) {
long diffInMilliseconds = finishDateTime.getTime() - startDateTime.getTime();
return TimeUnit.MILLISECONDS.toMinutes(diffInMilliseconds) / 60.0;
}

Converting milliseconds to Date object

I am having following code to convert milliseconds to Android Date object.
Date dateObj = new Date(milli);
But problem is that my milliseconds value is having GMT value added in it before i pass it to Date class, add when i print this date object i can see that date object is again adding GMT value in the milliseconds value and because of that my date is displayed as wrong.
So how can i generate Date object with out considering GMT value in it.
For example my milliseconds are 1385569800000 which is getting printed as below:
Wed, 27 Nov 2013 22:00:00 --> +5.30
But the current value of this time stamp without adding GMT is:
Wed, 27 Nov 2013 16:30:00
*UPDAE*
It is not just about printing the date in right format and with right date time.
But i want to use that date object to schedule TimeTask.
So basically i want to create Date object which has proper date time value in it with out adding extra GMT time added in it.

A Date is always in UTC. No need to change that.
When printing the date value, use SimpleDateFormat and call setTimeZone() on it before formatting the output string.
It is not just about printing the date in right format and with right date time.
But i want to use that date object to schedule TimeTask.
TimerTask is just a task and not its scheduling. Timer accepts a Date object for scheduling. The Date is in UTC there as well.

try my code if you a
long currentTime = System.currentTimeMillis();
TimeZone tz = TimeZone.getDefault();
Calendar cal = GregorianCalendar.getInstance(tz);
int offsetInMillis = tz.getOffset(cal.getTimeInMillis());
currentTime -= offsetInMillis;
Date date = new Date(currentTime);
it is work for me

You can try with joda-time API.
Joda-Time provides a quality replacement for the Java date and time classes. The design allows for multiple calendar systems, while still providing a simple API. The 'default' calendar is the ISO8601 standard which is used by XML. The Gregorian, Julian, Buddhist, Coptic, Ethiopic and Islamic systems are also included, and we welcome further additions. Supporting classes include time zone, duration, format and parsing.
http://joda-time.sourceforge.net/key_instant.html

A Date object simply represents a moment in time. Imagine you're on the phone to someone on a different continent, and you say "3...2...1...NOW!". That "NOW" is the same moment for both of you, even though for one person it's 9am and for the other it's 4pm.
You're creating a Date representing the moment 1385569800000 milliseconds after the Java epoch (the beginning of 1970, GMT). That is your "NOW", and it's fixed and unchanging. What it looks like converted into text, however, depends on which timezone you want to display it for. Java defaults to using GMT, which would be right if you were in Britain during the winter, but for (I'm guessing) India you want it in a different time zone. Laalto's answer shows you how to do that.

here is the code,that worked like charm for me:
public static String getDate(long milliSeconds, String dateFormat)
{
// Create a DateFormatter object for displaying date in specified format.
DateFormat formatter = new SimpleDateFormat(dateFormat);
// Create a calendar object that will convert the date and time value in milliseconds to date.
Calendar calendar = Calendar.getInstance();
calendar.setTimeInMillis(milliSeconds);
return formatter.format(calendar.getTime());
}

Getting Current Time for Booking

I know this is very simple question but I am not able to do it.
I have a code that gets current time but this time is not accurate.
booking.CreateDateTime = DateTime.Now.ToUniversalTime();
When I am booking at 12:00 then in database stores 1:00 that means 1 hour difference.
How can I get accurate time?

Use System.currentTimeMillis() to get the current GMT time in mili seconds since epoch.
Then you can use this value to create a new Date or Calendar object and localize it wherever the user is.

I'm not familiar with what you have there, but ToUniversalTime suggests to me that this is adjusting your time to some fixed time zone (probably GMT)
Use a Date to get the time right now, and then a Calendar to do any time zone changes on it that you want.
Example, assuming CreateDateTime is actually a string of what you said it was:
Date date = new Date();
Calendar calendar = new GregorianCalendar();
calendar.setTime(date);
booking.CreateDateTime = calendar.get(Calendar.HOUR_OF_DAY) + ":" + calendar.get(Calendar.MINUTE));

Get time of different Time zones on selection of time from time picker

I have an issue of converting selected hours and minutes to different time zones of countries.
Supposing if i select 10 am in India then i want to know at 10 am in india what will be the time in USA/New york and Tokyo.and Vice versa.
Any help is appreciable...
Thank you

please find the sollution below :
SimpleDateFormat sdf = new SimpleDateFormat("dd/MM/yyyy hh:mma");
TimeZone timezone = TimeZone.getDefault();
TimeZone utcTimeZone = TimeZone.getTimeZone("UTC");
Date d = new Date();
sdf.setTimeZone(timezone);
String strtime = sdf.format(d);
Log.e("str time gmt ",strtime);
sdf.setTimeZone(utcTimeZone);
strtime = sdf.format(d);
Log.e("str time utc ",strtime);
i think this will solve your problem

You can probably use Joda Time - Java date and time API. You can get the DateTimeZone depending on the Canonical ID defined in the Joda Time,
DateTimeZone zone = DateTimeZone.forID("Asia/Kolkata");
Joda Time has a complete list of Canonical ID from where you can get TimeZone depending on the Canonical ID.
So, if you want to get the local time in New York at this very moment, you would do the following
// get current moment in default time zone
DateTime dt = new DateTime();
// translate to New York local time
DateTime dtNewYork = dt.withZone(DateTimeZone.forID("America/New_York"));
For getting more idea you can refer Changing TimeZone

Try using Joda-Time library
check the org.joda.time.DateTimeZone class
Here is the API documentation for the same.

you can also get it using , Here no external API is needed
DateFormat format = new SimpleDateFormat("MMMMM d, yyyy, h:mm a");
TimeZone utc = TimeZone.getTimeZone("America/New_York");
System.out.println(utc.getID());
GregorianCalendar gc = new GregorianCalendar(utc);
Date now = gc.getTime();
System.out.println(format.format(now));
you can see more time zone on this Link
Output
America/New_York
December 29, 2012, 11:04 AM
If you don't know city name then you can also use it by Zone name as follow
DateFormat format = new SimpleDateFormat("MMMMM d, yyyy, h:mm a");
TimeZone cst = TimeZone.getTimeZone("US/Eastern");
System.out.println(cst.getID());
GregorianCalendar gc = new GregorianCalendar(cst);
Date now = gc.getTime();
format.setTimeZone(cst);
System.out.println(format.format(now))
Output
US/Eastern
December 29, 2012, 12:38 AM

Not really sure about the solution I'm going to provide but I think you can try it. GMT (Greenwich Mean Time) is a standard. I think you can keep it as a base and calculate the desired time. GMT standard is easily available too.
For example: While installing an OS like Windows XP or Windows 7, we select the time from a drop down menu. My point is, keeping this as the base, you can find the difference between the time zones in NY-US and Tokyo-Japan or vice versa as you desire it.
Hope this helps.