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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
...

Converting UTC date from server into local time

I am getting this string as Date from Server
2016-06-11T11:14:57.000Z
Since it is UTC, I want to convert to my local time.
SimpleDateFormat mFormat = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS'Z'");
SimpleDateFormat endFormat = new SimpleDateFormat("hh:mm a");
mFormat.setTimeZone(TimeZone.getTimeZone("GMT+5:00"));
Date date = mFormat.parse(mBooking.startTime);
However the date converted to 2:00AM
Now i don't get it why 11am is getting converted to 2:00AM
What wrong am i doing?

Because you don't set the timezone properly to each SimpleDateFormat indeed mFormat should be set to UTC and endFormat to GMT + 5, here is what you are supposed to do:
SimpleDateFormat mFormat = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS'Z'");
// Set UTC to my original date format as it is my input TimeZone
mFormat.setTimeZone(TimeZone.getTimeZone("UTC"));
Date date = mFormat.parse("2016-06-11T11:14:57.000Z");
SimpleDateFormat endFormat = new SimpleDateFormat("hh:mm a");
// Set GMT + 5 to my target date format as it is my output TimeZone
endFormat.setTimeZone(TimeZone.getTimeZone("GMT+5:00"));
System.out.println(endFormat.format(date));
Output:
04:14 PM

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));

Get correct long value from parsed Date (Timezone issue)

I'm trying to parse a date from a String and get the long value. The long value will be later sent to an SQL query.
here's my code:
String dayDate = "28-02-2013";
SimpleDateFormat sdf = new SimpleDateFormat("dd-MM-yyyy");
Date day = new Date();
try {
day = sdf.parse(dayDate);
} catch (ParseException pe) {
pe.printStackTrace();
}
System.out.println("day : "+day.toString()+ " long : " + day.getTime());
which gives the following output:
day : Thu Feb 28 00:00:00 EET 2013 long : 1362002400000
which is correct but not what I want since the long value results in Wed, 27 Feb 2013 22:00:00 GMT (http://www.epochconverter.com/) (I'm in a GMT+2 timezone). And i need to send to correct long value to sql.
Is there anyway to work around this without using external libraries?

SimpleDateFormat is locale-aware, meaning the date it parses is in your timezone. Midnight 28 Feb in GMT+2 is actually 10pm 27 Feb in GMT, the long value 1362002400000. I would add this to get the parsing right (would't bother using Calendar):
sdf.setTimeZone(TimeZone.getTimeZone("GMT"))
Again, when you print this date it uses SimpleDateFormat and that's why you can see EET in the output.
Passing this to database is a different story though once you get this right.

Use DateFormat.setCalendar(Calendar cal) to set a Calendar with GMT as its timezone, or use DateFormat.setTimeZone(TimeZone zone) with the GMT TimeZone. That will ensure that the resulting Date will be 00:00:00 in GMT instead of in EET.

If you add a timezone specifier to your string you can force java to use GMT for the conversion:
String dayDate = "28-02-2013";
SimpleDateFormat sdf = new SimpleDateFormat("dd-MM-yyyy z"); // z is a timezone specifier
Date day = new Date();
try {
day = sdf.parse(dayDate + " GMT"); // Use GMT timezone.
} catch (ParseException pe) {
pe.printStackTrace();
}
System.out.println("day : "+day.toString()+ " long : " + day.getTime());

You are converting between text and internal (Date) representations of dates and times without explicitly stating the time-zone. That never goes well.

Calendar calendar = Calendar.getInstance();
calendar.setTimeZone(TimeZone.getTimeZone("America/Los_Angeles"));
Date date = calendar.getTime();
Use your timezone String:
TimeZones

Unable to get the date in UTC format

I have written two functions - today() and todayUTC() - as:
public static Date today() {
Calendar cal = Calendar.getInstance();
return cal.getTime();
}
public static Date todayUTC() {
Calendar cal = Calendar.getInstance(TimeZone.getTimeZone("UTC"));
return cal.getTime();
}
But when I print the results of these functions using:
public void todayTest() {
Date date1 = OOTBFunctions.today();
System.out.println("today: "+date1);
Date dateUTC1 = OOTBFunctions.todayUTC();
System.out.println("todayUTC: "+dateUTC1);
}
I saw that both statements print the same value i.e.
today: Thu Aug 30 14:48:56 PDT 2012
todayUTC: Thu Aug 30 14:48:56 PDT 2012
Can anybody suggest what am I missing in UTC function that I am getting local timezone date.

Java uses the default Locale while printing and that is why you see that behavior. Use code like below to format and print it in the locale/format you want. Remember
When you create a Date object, it is always in UTC.
Display the date in the Locale of the user.
Store the date in UTC.
Code
final SimpleDateFormat sdf = new SimpleDateFormat("the format you want");
sdf.setTimeZone(TimeZone.getTimeZone("UTC"));
final String utcTime = sdf.format(new Date());
You doesn't need both today() and todayUTC() methods. keep and like below
public static Date nowInUTC()
{
return new Date();
}
You doesn't need to test anything.

Both of your methods will return the same value - a Date object doesn't have any notion of a time zone (unlike a Calendar). A Date just represents an instant in time, stored internally as the number of milliseconds since midnight January 1st 1970, UTC. Effectively, you've got two methods which are equivalent to:
return new Date(System.currentTimeMillis());
Date.toString() always uses the system default time zone.
If you want to maintain a date/time with a time zone, consider just using Calendar. If you want to format a particular instant in time in a time zone, just use SimpleDateFormat having set the time zone.
Ideally, change to use Joda Time instead of Date or Calendar though - it's a much cleaner API.