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How to format date/time string? (Java)

Hi can anyone help please? I am trying to format a date and time string.
Currently it looks like this "20160112T110000Z" and I need it to be "2016-01-12T11:00:00Z"
The string without the special characters are returned from a 3rd party recurrence library. I need to convert it to have the special characters before parsing it to a Calendar object.
Can anyone help please?
The code that I have so far looks like:
final String TIMEFORMAT = "yyyy-MM-dd'T'HH:mm:ss'Z'";
String string = "20160112T110000Z";
SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss'Z'");
Date date = format.parse(string);
System.out.println(date);
However this just does not work.
Any suggestions are appreciated

You have to read the string with a format matching the source, this gives you a correct Date.
Then simply write it with the format you want :
String string = "20160112T110000Z";
String originalStringFormat = "yyyyMMdd'T'HHmmss'Z'";
String desiredStringFormat = "yyyy-MM-dd'T'HH:mm:ss'Z'";
SimpleDateFormat readingFormat = new SimpleDateFormat(originalStringFormat);
SimpleDateFormat outputFormat = new SimpleDateFormat(desiredStringFormat);
try {
Date date = readingFormat.parse(string);
System.out.println(outputFormat.format(date));
} catch (ParseException e) {
e.printStackTrace();
}

try this
DateFormat formatter = new SimpleDateFormat("dd/MM/yyyy");
// you can change format of date
Date date = formatter.parse(strDate);
Timestamp timeStampDate = new Timestamp(date.getTime());
return timeStampDate;

Date Conversion (String to java.sql.Date) in java

In my code, I've to convert a String value(Input) to java.sql.Date format. The problem I am facing is , the input date format is undefined, and it could be in any format. For example , input string may be "Jan 10,2014" or "01-10-2014" or "2014/Jan/10". So now I need to convert this input value into java.sql.Date(DD/MMMM/YYYY). Is there any way to do this conversion?

That is not possible.
You cannot differentiate dd/MM/yyyy and MM/dd/yyyy.
You really need to know the format otherwise your program will probably not behave the way you want.

Try using a List of all the patterns mentioned above using SimpledateFormat.
Something like this:
SimpleDateFormat format1 = new SimpleDateFormat("MMM dd,yyyy");
SimpleDateFormat format2 = new SimpleDateFormat("MM-dd-yyyy");
SimpleDateFormat format3 = new SimpleDateFormat("yyyy/MMM/dd");
// Note: be sure about the format, or else you may end up assigning incorrect values
List<DateFormat> list = new ArrayList<DateFormat>();
list.add(format1);
list.add(format2);
list.add(format3);
for (DateFormat format : list) {
try {
System.out.println(format.parse("Jan 10,2014"));
// Match found. Take action
} catch (ParseException exception) {
// Ignore. Try other pattern
}
}

How can I convert this string to a standard date in java?

Earlier I posted the following question: How can I convert this date in Java?
But now I would like to know how I can convert this string into a date/time.
2010-03-15T16:34:46Z
For example: 03/15/10
UPDATED:
String pattern = "MM/dd/yy 'at' HH:mm";
Date date = new Date();
try {
date = new SimpleDateFormat(pattern).parse(q.getUpdated_at());
} catch (ParseException e) {
e.printStackTrace();
}
dateText.setText(new SimpleDateFormat("MM/dd/yy 'at' hh:mma").format(date));
Gives me a result like:
Mon Mar 15 16:34:50 MST 2010
How can I format it to be
03/15/10 at 4:34PM
?

Both SimpleDateFormat and joda-time DateTimeFormat can parse this, using this pattern:
String pattern = "yyyy-MM-dd'T'HH:mm:ss'Z'";
For example:
Date date = new SimpleDateFormat(pattern).parse(dateString);
And (joda-time):
DateTimeFormatter dtf = DateTimeFormat.forPattern(pattern);
DateTime dateTime = dtf.parseDateTime(s);
Update
You have 2 date formats involved - one for parsing the input, and one for formatting the output. So:
dateText.setText(new SimpleDateFormat("MM/dd/yy 'at' hh:mma").format(date));
(Of course, for the sake of optimization, you can instantiate the SimpleDateFormat only once, and reuse it)

In a nutshell, you want to convert a date in a string format to a date in another string format. You have:
2010-03-15T16:34:46Z
and you want
03/15/10 at 4:34PM
You don't want to end up using java.util.Date object as you initially implied in your question. You also don't want to use its toString() since that returns a fixed format as definied in its javadoc.
The answer of Bozho still applies. Use java.text.SimpleDateFormat. First, you need to parse the date in string format into a Date object so that you can format it back into another string format.
// First parse string in pattern "yyyy-MM-dd'T'HH:mm:ss'Z'" to date object.
String dateString1 = "2010-03-15T16:34:46Z";
Date date = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss'Z'").parse(dateString1);
// Then format date object to string in pattern "MM/dd/yy 'at' h:mma".
String dateString2 = new SimpleDateFormat("MM/dd/yy 'at' h:mma").format(date);
System.out.println(dateString2); // 03/15/10 at 4:34PM

If you want to format output string, change following line in your code
dateText.setText(date.toString());
to
dateText.setText(String.format("%1$tm/%1$td/%1$ty at %1$tl:%1$tM%1$Tp", date));

String to Date in Java

HI,
I am converting String to Date format. But it returns wrong dates. for example,
String startDate = "08-05-2010"; // (MM/dd/yyyy)
I want to convert this to "Date" object like this, 05-JUL-10
How to do that? I tried like this
SimpleDateFormat dateFormat = new SimpleDateFormat("dd-MMM-yy");
scal1.setTime(dateFormat.parse((startDate)));
but i am getting "Unparseable date:" .

If you want to convert a date string of one format to another format, you can use format() and parse() methods of SimpleDateFormat class
First you need to parse the string to a date object using parse() method setting the source pattern and then format the date object using format() method setting the target pattern:
SimpleDateFormat sourceFormat = new SimpleDateFormat("MM-dd-yyyy");
Date sourceFormatDate = sourceFormat.parse("08-05-2010");
SimpleDateFormat destFormat = new SimpleDateFormat("dd-MMM-yy");
String destFormatDateString = destFormat.format(sourceFormatDate);
System.out.println(destFormatDateString); // 05-Aug-10

Unless you've left something out, it looks like you're trying to parse it with the wrong format, i.e. you have an mm-dd-yyyy, and you're trying to parse it with the format dd-MMM-yy. Try a separate date format for what you're parsing from what you're encoding.

SimpleDateFormat format = new SimpleDateFormat(“yyyy-MM-dd”);
String strDate = “2007-12-25″;
Date date = null;
try {
date = format.parse(strDate);
} catch (ParseException ex) {
ex.printStackTrace();
}

The format dd-MMM-yy you use to parse the string is wrong; the format should be dd-MM-yyyy.
String startDate = "08-05-2010";
DateFormat dateFormat = new SimpleDateFormat("dd-MM-yyyy");
Date date = dateFormat.parse((startDate));
Note that Date objects themselves do not have a format: a Date objects just represents a date and time value, just like an int is just a number, and doesn't have any inherent formatting information. If you want to display the Date in a certain format, you'll have to use a DateFormat object again to format it:
DateFormat dateFormat = new SimpleDateFormat("dd-MMM-yy");
System.out.println(dateFormat.format(date));
// output: 08-May-10

Date conversion in Java

How can I take a string in a format such as: 2008-06-02 00:00:00.0 and convert it to: 02-Jun-2008?
Can I somehow take the original string, convert it to a Date object, then use a formatter to get the final output (rather than parsing the string myself)? Thanks!

You can use SimpleDateFormat to convert between a String and a Date object and vice versa based on a pattern. Click the API link, you'll see patterns being explained in detail. A 4-digit year can be represented with yyyy, a 3-character month abbreviation can be represented with MMM and so on.
First you need to parse the String of the first format into a Date object:
SimpleDateFormat sdf1 = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss.SSS");
Date date = sdf1.parse(inputString);
Then you need to format the Date into a String of the second format:
SimpleDateFormat sdf2 = new SimpleDateFormat("dd-MMM-yyyy", Locale.ENGLISH);
String outputString = sdf2.format(date);
Note that you need to take the Locale into account as well to get the month to be printed in English, else it will use the platform's default locale to translate the month.

Use 2 instances of SimpleDateFormat class. One for converting your input string to date and second to convert date back to string but in another format.
Here is an example of using SimpleDateFormat.

DateFormat startFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss.S");
DateFormat endFormat = new SimpleDateFormat("dd-MM-yyyy");
String outputString = null;
try {
Date date = startFormat.parse(inputString);
outputString = endFormat.format(date);
} catch(ParseException pe) {
throw new IllegalArgumentException(inputString + " is not properly formated.", pe);
}

You can definitely use SimpleDateFormat class like others have recommended.
Another suggestion if it applies in your case. If you are getting this data from a sql query you can also use to_char() method to format it in the query itself. For example: to_char(column_name,'DD-MON-YYYY')