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SimpleDate format is not converting time to IST

I am trying to get time (HH:MM) from below code in IST format but it still display UTC date, time.
Please help.
public static void main (String args[]) throws ParseException {
String date = "2021-07-05T14:17:00.000Z";
Calendar now = Calendar.getInstance();
TimeZone timeZone = now.getTimeZone();
String timezoneID = timeZone.getID();
// Convert to System format from UTC
SimpleDateFormat format1 = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS'Z'");
Date actualDate = format1.parse(date);
format1.setTimeZone(TimeZone.getTimeZone(timezoneID));
String date1 = format1.format(actualDate);
String time = date1.substring(11, 16);
String timezoneValue = TimeZone.getTimeZone(timezoneID).getDisplayName(false, TimeZone.SHORT);
String finalTime = time + " " + timezoneValue;
System.out.print(finalTime);
}

java.time
I strongly recommend that you use java.time, the modern Java date and time API, for your date and time work. Then your task becomes pretty simple. Rather than a formatter for your input format I want to define a formatter for your desired time format:
private static final DateTimeFormatter TIME_FORMATTER
= DateTimeFormatter.ofPattern("HH:mm zzz", Locale.ENGLISH);
Now the operation goes in these few lines:
String date = "2021-07-05T14:17:00.000Z";
String finalTime = Instant.parse(date)
.atZone(ZoneId.systemDefault())
.format(TIME_FORMATTER);
System.out.println(finalTime);
Output when I ran in Europe/Dublin time zone:
15:17 IST
Here IST is for Irish Summer Time. IST has several meanings, and I wasn’t sure which one you intended. Also many of the other popular time zone abbreviations are ambiguous. IST may also mean Israel Standard Time, but not here, since Israel uses Israel Daylight Time or IDT at this time of year. One other interpretation is India Standard Time used in India and Sri Lanka, So let’s try running the code in Asia/Kolkata time zone.
19:47 IST
I am exploiting the fact that your string is in ISO 8601 format, the format that the classes of java.time parse and also print as their default, that is, without any specified formatter.
What went wrong in your code?
Your bug is here:
SimpleDateFormat format1 = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS'Z'");
You must never hardcode Z as a literal in your format pattern, which is what you are doing when enclosing it in single quotes. The Z is a UTC offset and needs to be parsed as such so that Java knows that your date and time are in UTC (which is what Z means). When you hardcode the Z, SimpleDateFormat understands the date and time to be in the default time zone of the JVM. So when afterward you try to convert into that time zone, the time of day is not changed. You’re converting into the time zone you already had. It’s a no-op.
Links
Oracle tutorial: Date Time explaining how to use java.time.
Wikipedia article: ISO 8601
Time Zone Abbreviations – Worldwide List

You are parsing the date using your default TimeZone, not UTC.
You never called format1.setTimeZone before parsing. A DateFormat uses the default timezone unless you set it to something else.
Let’s look at each line of your code:
Calendar now = Calendar.getInstance();
TimeZone timeZone = now.getTimeZone();
That is getting the default TimeZone. You don’t need a Calendar object for that; just call TimeZone.getDefault().
String timezoneID = timeZone.getID();
There is no reason to call that. You already have a TimeZone object. Converting it to a string ID and back to a TimeZone is a pointless round-trip operation. So, you should remove all uses of timezoneID.
SimpleDateFormat format1 = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS'Z'");
That is the problem. The DateFormat doesn’t treat the 'Z' as anything special; it’s just a literal character which the DateFormat knows not to parse.
You need to actually tell the DateFormat that it’s parsing a UTC time:
SimpleDateFormat format1 = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS'Z'");
TimeZone utc = TimeZone.getTimeZone(ZoneOffset.UTC);
format1.setTimeZone(utc);
Date actualDate = format1.parse(date);
Instead of cutting out pieces of a formatted string, make a new DateFormat that does exactly what you want:
DateFormat timeFormat = new SimpleDateFormat("HH:mm z");
String finalTime = timeFormat.format(actualDate);
Since a SimpleDateFormat always uses the default TimeZone when it is created, there is no need to call this format object’s setTimeZone method.
I should mention that the java.time and java.time.format packages are much better for working with dates and times:
String date = "2021-07-05T14:17:00.000Z";
Instant instant = Instant.parse(date);
ZonedDateTime utcDateTime = instant.atZone(ZoneOffset.UTC);
ZonedDateTime istDateTime =
utcDateTime.withZoneSameInstant(ZoneId.systemDefault());
String finalTime = String.format("%tR %<tZ", istDateTime);
// Or:
// String finalTime = istDateTime.toLocalTime() + " "
// + itsDateTime.getZone().getDisplayName(
// TextStyle.SHORT, Locale.getDefault());

format1.setTimeZone(TimeZone.getTimeZone("Asia/Kolkata"));
is what you need since the 3-letter zone names are really deprecated. Plus:
String timezoneValue = format1.getTimeZone().getDisplayName(false, TimeZone.SHORT);

The method Calendar.getInstance() gets a calendar using the default time zone and locale - UTC±00:00.
Use "IST" instead of timeZone.getID().
Exemple:
String date="2021-07-05T14:17:00.000Z";
Calendar now = Calendar.getInstance();
TimeZone timeZone = now.getTimeZone();
String timezoneID = "IST"; // <<<<<
// Convert to System format from UTC
DateFormat format1 = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS'Z'");
Date actualDate = format1.parse(date);
format1.setTimeZone(TimeZone.getTimeZone(timezoneID));
String date1 = format1.format(actualDate);
String time = date1.substring(11, 16);
String timezoneValue = TimeZone.getTimeZone(timezoneID).getDisplayName(false, TimeZone.SHORT);
String finalTime = time + " " + timezoneValue;
System.out.print(finalTime);

android getDate from milliseconds stored in String field

I have a date stored in a String field in SQLITE with the String value
"/Date(1411472160000+0100)/"
how can I convert this back into a date format , the code below doesn't work. I think I need to convert from the milliseconds first but I cant see how to even get the above text into a long format first ?
any suggestions ?
Date convertedDate = new Date();
SimpleDateFormat dateFormat = new SimpleDateFormat("dd/MM/yyyy HH:mm",
java.util.Locale.getDefault());
convertedDate = dateFormat.parse(dateString);
return dateFormat.format(convertedDate);

Well, a substring from the indexOf("(") to the indexOf("+") and you should find the date in milli.
From there, I believe you can find the date ;)
String s = "/Date(1411472160000+0100)/";
s = s.substring(s.indexOf("(") + 1, s.indexOf("+"));
Date d = new Date(Long.parseLong(s));
With the same structure, you can find the timezone (+0100) (from "+" to ")") and work with a Calendar to find the right time for the right time area.

First you have to parse out the time value from String i.e. "1411472160000+0100" part.
Here in "1411472160000+0100" , "+0100" is the timezone info. If you don't want to consider the timezone, then you can take following approach.
Approach-1
long timestamp = 1245613885;
Calendar calendar = Calendar.getInstance();
calendar.setTimeZone(TimeZone.getDefault());
calendar.setTimeInMillis(timestamp * 1000);
int year = calendar.get(Calendar.YEAR);
int day = calendar.get(Calendar.DATE);
int hour = calendar.get(Calendar.HOUR_OF_DAY);
int minute = calendar.get(Calendar.MINUTE);
then to get the date in your specified format you can use-
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
String dateString = sdf.format(calendar.getTime());
System.out.println(dateString); // 2009-06-21 15:51:25
Besides this approach, there is an excellent Java Date library called JodaTime.
If you want to incorporate the timezone info , you can refer to this constructor from JodaTime.
http://www.joda.org/joda-time/apidocs/org/joda/time/DateTime.html#DateTime-long-org.joda.time.DateTimeZone-

Print a UTC time in my local timezone

I have a timestamp coming from an API in this format:
yyyy-MM-dd'T'HH:mm:ss.SSSSSS
I want to format it for the user in their own timezone (on android). This is what I'm doing:
String timestampFromApi = "...";
DateFormat df1 = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss", Locale.ENGLISH);
Date date = df1.parse(timestampFromApi);
DateFormat df2 = new SimpleDateFormat();
Log.v(TAG, "In your timezone: " + df2.format(date));
But this prints the time in UTC. For example, if the timestamp happened at 4pm UTC time, and I am in PDT, the result is that it still prints "4pm".
I checked the timezone being used:
df2.getTimeZone()
and it does print out PDT for my device. What have I done wrong here?
Thanks

You're on the right track. You got the UTC time from the server, but now you just need to calculate the local offset when formatting. Try something like this:
private String formatTime(String timestampFromApi){
SimpleDateFormat df1 = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss", Locale.ENGLISH);
df1.setTimeZone(TimeZone.getTimeZone("UTC"));
Date date = df1.parse(timestampFromApi);
Log.v(TAG, "In your timezone: " + df1.format(getAdjustedTime(date.getTime())));
}
private Date getAdjustedTime(long utcDate){
return new Date(utcDate + TimeZone.getDefault().getOffset(new Date().getTime()));
}
The getAdjustedTime() method will create a new Date object based on the UTC-offset from the local TimeZone.

Getting TimeZone instance from a date

With the following code-
Timestamp ts = (Timestamp)results.get(0);
SimpleDateFormat sdf = new SimpleDateFormat("MM/dd/yyyy HH:mm:ss Z");
System.out.println(sdf.format(new Date(ts.getTime())));
I get output as: 04/29/2013 15:08:30 +0530
I wanted to create a TimeZone instance from the timestamp, so tried this-
SimpleDateFormat FORMATTER = new SimpleDateFormat("Z");
String tzString = FORMATTER.format(ts);
// the tzString comes out to be +0530 (which is correct)
TimeZone tz = TimeZone.getTimeZone(tzString);
System.out.println(tz);
But the final TimeZone instance is of GMT as its not able to identify +0530.
So, how can I get a correct TimeZone instance here?

You cannot get a TimeZone from a java.sql.Timestamp because it does not contain one. In your case you are simply getting your default TimeZone. It does not make sense. It is the same as TimeZone.getDefault();

Use a lowercase z in your pattern. That should return "GMT+0530", which will work.

Instead of using a SimpleDateFormat, you can simply do this:-
Calendar cal = Calendar.getInstance();
cal.setTime(new Date(ts.getTime()));
TimeZone tz = cal.getTimeZone();
System.out.println(tz);

I tried this code below:
Timestamp ts = new Timestamp(System.currentTimeMillis());
Then to get the TimeZone instance from the timestamp, I did this:
SimpleDateFormat FORMATTER = new SimpleDateFormat("Z");
TimeZone tzone = FORMATTER.getTimeZone();
System.out.println(tzone.getDisplayName());
System.out.println(tzone.getID());
I got:
Central European Time
Europe/Berlin
So I got my timezone which is +0200 instead of GMT.
Hope this is what you want.

why local timeZone String is getting appended in the UTC date?

I want to get a Date Object in UTC Time Zone so i am converting it first to a String which is returing me correct UTC Date String but when i am again parsing it to Date object then Local Time Zone String(ie. IST) is getting appended in that Date instead of UTC.
Date date = new Date();
DateFormat timeFormat = new SimpleDateFormat("MM/dd/yyyy HH:mm:ss");
timeFormat.setTimeZone(TimeZone.getTimeZone("UTC"));
String estTime = timeFormat.format(date);
date = new SimpleDateFormat("MM/dd/yyyy HH:mm:ss", Locale.ENGLISH).parse(estTime);

A Date doesn't have a timezone, it represents a moment in time. It holds the time in milliseconds.
You can't have a Date with a format, it doesn't work that way. If you need to show the Date in a GUI, console or anywhere else, that's when you use a SimpleDateFormat like you did to change it to a String in the format you want.