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Time String to time representation Java

I have a string like this 210115 I want to represent it as 21:01:15 any ideas?.
I tried using Gregorian calendar but it adds date to it which I don't want
SimpleDateFormat sdf = new SimpleDateFormat("HHmmss");
Date date = new Date();
try{
date = sdf.parse("210115");
}
catch(Exception e){
}
Calendar calendar = GregorianCalendar.getInstance();
calendar.setTime(date);
System.out.print(calendar.getTime());
Output is Thu Jan 01 21:01:15 UTC 1970 but what I want is just 21:01:15
Thanks.

To output a formatted date, you use another SimpleDateFormat object with a pattern with the format you want.
In this case, it sounds like you might want to use something like
SimpleDateFormat outputFormat = new SimpleDateFormat("HH:mm:ss");
System.out.println( outputFormat.format(date) );

So what you want is just a time, without time zone. I would recommend using the LocalTime class, which is exactly that, instead of the Date class.
LocalTime time = LocalTime.parse("210115", DateTimeFormatter.ofPattern("HHmmss"));

If u r getting the date string in "210115" this format and you want it in "21:01:15" format then why are you using date format.
Simply do string operation as:
String time="210115";
String newtime=time.substring(0,2)+":"+time.substring(2,4)+":"+time.substring(4,6);
System.out.println(newtime);
you will get the required format.21:01:15

java date and time from timestamp

I am working on android app with achartengine where I am making a TimeSeries linegraph. I have stored all my variables inside an Arraylist. Since I need correct date object to insert in the time axis of my chart I am using,
int count = list.size();
Date[] dt = new Date[count];
for(int i=0;i<count;i++){
long a = Long.parseLong(list.get(i).get("time"));
dt[i] = new Date(a);
}
Here long a has the timestamp . With above piece of code. I am able to get dt as 09-Apr-2014 but I need the date to be shown as 09-Apr 12:55 . How can I do that,
I tried using the folllowing
SimpleDateFormat sdfDate = new SimpleDateFormat("MM-dd HH:mm");
Date now = new Date();
String strDate = sdfDate.format(now);
But Since strDate is a string I cannot use it as dt[i] = strDate which will throws an error as one is Date and another is String.
How can I solve this ?
Thanks

You can solve it this way:
dt[i] = sdfDate.parse(strDate);

If you really just need the date strings, you can do this:
int count = list.size();
String[] dt = new String[count];
for (int i = 0; i < count; i++) {
long a = Long.parseLong(list.get(i).get("time"));
Date d = new Date(a);
SimpleDateFormat dateFormat = new SimpleDateFormat("MM-dd HH:mm");
dt[i] = dateFormat.format(d);
}
Or, if you actually need the Date array, just format the dates on the fly as you need them.

Your question is misguided - you are showing how you create Date objects in the code, yet what you want to fix is how you show them.
The Date array will have dates precisely to the millisecond. The default toString() method of the Date objects shows only the day, that's why you're not seeing the time.
It is inherently the UIs responsibility to decide on the format of time that it is going to print, hence you should pass the Date array to the UI (or up to the point of printing) and format them there.

The DateFormat can do both (date to string representation and back):
DateFormat formatter = new SimpleDateFormat( "dd-MM-yyyy HH:mm:ss" );
Date to String:
Date date = new Date();
String sDate = formatter.format( time );
String to Date:
Date date = formatter.parse(sDate );
When you store the date, you should store it as precise as possible (milliseconds). For displaying it as a string, you can use whatever format you want.

Date error in android to store in sqlite

I am trying to in insert date into sqlite using:
SimpleDateFormat format = new SimpleDateFormat("yyyyMMdd");
String data = format.format(new Date(19900101));
System.err.println("Time is.."+format.format(19900101));
But i am getting 19700101 in log. i am getting same result even if i change the dates as 20000101 or any thing.
Any one suggest me why it happens?

the code is wrong
SimpleDateFormat format = new SimpleDateFormat("yyyyMMdd");
Date data = format.parse("19900101");
System.out.println("Time is.."+data );
when u use new Date(123) it expects some time in milliseconds i think

Change your code as for formatting current string to date :
SimpleDateFormat format = new SimpleDateFormat("yyyyMMdd");
Date convertedDate = (Date) format.parse("19900101");
SimpleDateFormat formats = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
String fmconvertedDate =formats.format(convertedDate);
System.err.println("Time is.."+fmconvertedDate);
and output is :
Time is..1990-01-01 00:00:00

How to get particular parts of a DateTime object?

I have a DateTime object DT which stores current time. When I print DT, I want it to only print the time part, ie HH-MM-SS (H = hours, M = minutes, S = seconds) and ignore the date part.
How can I do this ? For that matter, is it even possible to create a date time object which will only contain HH-MM-SS and nothing related to date ? If that is true, then I can simply print it instead of extracting the HH-MM-SS part.
Thanks.

If you only want the time, you should use a LocalTime instead of a DateTime. You can use DateTime.toLocalTime() to get the time part of an existing DateTime.
If you actually want to keep the DateTime but only reveal the time part when formatting, you can create a DateTimeFormatter with a pattern which only includes the time parts, but I'd usually consider this a design smell.

You can use Java date formatter which is in java.util.Date package.
Like :
Date todaysDate = new java.util.Date();
1. // Formatting date into yyyy-MM-dd HH:mm:ss e.g 2008-10-10 11:21:10
SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
String formattedDate = formatter.format(todaysDate);
2. // Formatting date into yyyy-MM-dd e.g 2008-10-10
formatter = new SimpleDateFormat("yyyy-MM-dd");
formattedDate = formatter.format(todaysDate);
3. // Formatting date into MM/dd/yyyy e.g 10/10/2008
formatter = new SimpleDateFormat("MM/dd/yyyy");
formattedDate = formatter.format(todaysDate);

With Java you can do it like this
Date obj = new Date() ;
System.out.println(new SimpleDateFormat("hh:mm:ss").format(obj)) ;
but it could be an expensive call.
But jodatime gives LocalTime which you can try out.

Help Needed with Date Format in java

I have My Database data in this format
18-NOV-10
I have to pass the same format into java.util.Date like this
Date date = new java.util.Date(dateformater);
so that the result of java.util.Date is like this 18-NOV-10
Is this possible ??
I tried this way
String strDate = "12-NOV-07";
SimpleDateFormat sdfSource = new SimpleDateFormat("dd-MMM-yy");
Date date = sdfSource.parse(strDate);
System.out.println(date);
But i am getting the result as "Mon Nov 12 00:00:00 IST 2007 " which i want it only
12-NOV-07"

You can use java.text.DateFormat (actually SimpleDateFormat) to get you where you want to go, but maybe you shouldn't be storing the dates as strings in your database. It will do output and parsing.
SimpleDateFormat sdf =
new SimpleDateFormat("DD-MMM-YY");
Date parsed = sdf.parse(dateString);
See http://javatechniques.com/blog/dateformat-and-simpledateformat-examples/
Once you get the Date, you can turn it into the format you want but it will be held in memory as a Date object. You can get it in the form you want using
String dateString = sdf.format(parsed);

As others have pointed out, you should probably store your dates as dates, not strings; nevertheless...
If you want to turn a Date back into a string in that format you can use the following:
DateFormat formatter = new SimpleDateFormat("dd-MMM-yy");
Date date = new Date();
String dateStr = formatter.format(date); // Gives "22-May-11"
If you need MAY instead of May, just use toUpperCase() on the resultant string.

DateFormat sdf = new SimpleDateFormat("dd-MMM-yy");
Date d = sdf.parse("18-NOV-10");

Try System.out.println(sdfSource.format(date).toUpperCase()); instead. The Date object will always have a time component to it; there is no way to "disable" that feature. What you can do instead is to ignore it in your calculations and display. If all Date objects you use are set to the same time of the day, then you can safely ignore the effect of the time component in your comparisons. If you look carefully, the time component of your Date object is set to midnight.