Dateformat Parse - Not Return Date in Utc

DateFormat parse - not return date in UTC

Excuse me for mentioning it, I suspect that there is no problem in your code, there’s only confusion. If you think the old Date class is behaving confusingly, allow me to be the first of many to agree with you. The good and sound solution to this problem is you stop using Date and start using the modern Java date and time API instead.

Since you are coding for Android, you first step is to get the ThreeTenABP, the library for Android that offers the modern API (if you were using Java 8 or 9, you could skip this step since the modern API wold be built in). The details are described in this question: How to use ThreeTenABP in Android Project. Now you can do:

    DateTimeFormatter formatter = DateTimeFormatter.ofPattern("uuuu-MM-dd'T'HH:mm:ss Z");
    String dateUTCAsString = "2017-11-15T12:54:25 +0000";
    Instant dateResult = OffsetDateTime.parse(dateUTCAsString, formatter).toInstant();
    System.out.println(dateResult);

On my computer this just printed:

2017-11-15T12:54:25Z

The Z at the end means Zulu time zone or UTC.

As you may know, System.out.println(dateResult) implicitly calls the toString method of the dateResult object. Objects of the class Instant produce the above format, always in UTC, as I understood you wanted. The Instant class is the natural replacement for the old-fashioned Date class for most purposes. Internally the Instant holds the number of seconds and nanoseconds since the epoch, which is defined as January 1 1970 at 0:00 midnight UTC. I encourage you to consider this an irrelevant implementation detail. An Instant is a point on the time-line.

What went wrong?

You asked for a date in UTC. Depending on how you look at it, you can or cannot have this.

• On one hand a Date is implemented as the number of seconds and milliseconds since the epoch, so if you use the above definition of the epoch, you may say that it is always in UTC.
• On the other hand you shouldn’t worry about implementation details. Conceptually a Date (like an Instant) is a point on the time-line, and does not and cannot have a time zone or offset; it cannot be in UTC. To make matters more confusing, when you do "getCurrentDateUTC: dateResult = " + dateResult, then dateResult.toString() is implicitly called. This method grabs your JVM’s time zone setting and converts the date-time to this zone and uses it for the generated string (without modifying the Date object). This is why you will see the time in EET on your computer or device no matter which Date you try to print.

java.time or JSR-310

The modern date and time API is know as java.time or JSR-310. One good source for learning to use it is the Oracle tutorial.

DateFormat format method doesn't display a parsed date to a particular TimeZone

There are two different topics here; parsing and formatting.

1. Parsing

SimpleDateFormat.parse() will try to parse the timezone from the supplied date string. If the date string you are parsing does not include an explicit timezone, then the "default" timezone on the SimpleDateFormat object will be used. You can set the default time zone with the setTimeZone() method. Please see the API docs for SimpleDateFormat.parse() and DateFormat.setTimeZone() for reference.

Here is an example that shows how the parsing is influenced by the timezone set with setTimeZone():

    String dateString = "2015.12.10 13:58:18";

    SimpleDateFormat sdf1 = new SimpleDateFormat("yyyy.MM.dd HH:mm:ss");
    sdf1.setTimeZone(TimeZone.getTimeZone("GMT"));
    Date date1 = sdf1.parse(dateString);

    SimpleDateFormat sdf2 = new SimpleDateFormat("yyyy.MM.dd HH:mm:ss");
    sdf2.setTimeZone(TimeZone.getTimeZone("EST"));
    Date date2 = sdf2.parse(dateString);

    // Shows that the parsing honours time zone -- will print:
    // Thu Dec 10 14:58:18 CET 2015 (original date was parsed as GMT)
    // Thu Dec 10 19:58:18 CET 2015 (original date was parsed as EST)
    System.out.println(date1);
    System.out.println(date2);

2. Formatting

Assuming that the date has been parsed correctly, then your problem is with the formatting. You need to set the timezone for the actual SimpleDateFormat object that you are using for formatting. I modified your code to do this and it will now print what you expet:

    Calendar cal = Calendar.getInstance();
    cal.setTime(alreadyParsedDateTime);
    SimpleDateFormat sdf3 = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss");
    sdf3.setTimeZone(TimeZone.getTimeZone("UTC"));

    // Prints: 2015-12-23T23:00:00 for your example date string
    System.out.println(sdf3.format(cal.getTime()));

How to parse a UTC offset dateformat string into the resulting date separated by | symbol

Your String 2019-12-25T17:00:00-05:00 represents UTC timezone with offset UTC offset, so use OffsetDateTime for parsing that string

OffsetDateTime odt = OffsetDateTime.parse("2019-12-25T17:00:00-05:00");

System.out.println(odt.format(DateTimeFormatter.ofPattern("MMM d | E | hh:mm a", Locale.US)));

If you want to set particular time zone you can use atZoneSameInstant to pass ZoneId for eaxmple

ZoneId zone = ZoneId.of("America/Chicago");
ZonedDateTime zdt = odt.atZoneSameInstant(zone);

Java Can't Parse UTC Date with SimpleDateFormat

This date:

"2014-01-09T17:10:14Z"

has a format of
"yyyy-MM-dd'T'HH:mm:ss'Z'"

(or in Java 7 "yyyy-MM-dd'T'HH:mm:ssX")

So of course it will be impossible to parse it with a format dd-MM-yyyy.

The formatting string needs to be compatible with the input!

(Note I gave a literal Z, this is back compatible. Java 7 actually understands ISO8601 and you could use an X there to have it actually be parsed.)

SimpleDateFormat with timezone displaying dates in my timezone, how do I fix this?

You can use the modern java.time package instead and specially ZonedDateTime that handles time zones.

String str = "2019-12-20T00:00:00.000-05:00";
ZonedDateTime zonedDateTime = ZonedDateTime.parse(str);

And when showing it in the UI use DateTimeFormatter to convert it to a formatted string

DateTimeFormatter formatter = DateTimeFormatter.ISO_DATE_TIME; 

or with some custom format

DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm");

which will give you for the 2 formats

System.out.println(formatter.format(zonedDateTime));

2019-12-20T00:00-05:00

2019-12-20 00:00

Java SimpleDateFormat interpret parse-string as UTC

My assumption was wrong,

22.09.1985 00:00UTC is actually 22.09.1985 02:00CET

so

SimpleDateFormat sdf = new SimpleDateFormat("dd/MM/yyyy");
sdf.setTimeZone(TimeZone.getTimeZone("UTC"));
Date d = sdf.parse("22/09/1985");

is exactly what i wanted, the date i compared it with was wrong.

Parsing datetime to UTC

Thank you guys for your help that's what i wonted i turn out that if the date in UTC you should start with parsing in the utc format that will keep the date as its the for formating it to your local timezone format it with local time zone

   private String getDate(String dateString) {
            SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss");
            formatter.setTimeZone(TimeZone.getTimeZone("UTC"));
            Date value = null;
            try {
                value = formatter.parse(dateString);
            } catch (ParseException e) {
                e.printStackTrace();
            }
            SimpleDateFormat dateFormatter = new SimpleDateFormat("hh:mm aa");
            dateFormatter.setTimeZone(TimeZone.getDefault());
            String dt = dateFormatter.format(value);

            return dt;
        }

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