Develop Reference

Java DateTime parse

I have the following code to simply parse a date and time to a format
SimpleDateFormat sdfClient = new SimpleDateFormat("yyyyMMddhhmmss.s");
SimpleDateFormat sdfFormat = new SimpleDateFormat("dd/MM/yyyy hh:mm:ss");
pmList.add(sdfClient.format(sdfFormat.parse(pmData[k].retrievalTime)));
Wanna change the format to sdfClient but for some reason eclipse throws an error:
java.text.ParseException: Unparseable date: "20140623135000.0"
at java.text.DateFormat.parse(DateFormat.java:357)
at com.syntronic.client.GenerateCSV.writepmData(GenerateCSV.java:220)
at com.syntronic.client.GenerateCSV.writeMEData(GenerateCSV.java:187)
at com.syntronic.client.GenerateCSV.<init>(GenerateCSV.java:87)
at com.syntronic.client.Client.main(Client.java:213)
Anyone knows the reason why?

It should be just the other way around:
pmList.add(sdfFormat.format(sdfClient.parse(pmData[k].retrievalTime)));
Explanation:
pmList.add(
sdfFormat.format( <-- Gives a string 23/06/2014 01:50:00
sdfClient.parse( <-- Gives a Date corresponding to the time 20140623135000.0
pmData[k].retrievalTime <-- Time 20140623135000.0
)
)
);

You've got your formatter and parser mixed about
pmList.add(sdfClient.format(sdfFormat.parse(pmData[k].retrievalTime)));
Basically says, "yyyyMMddhhmmss.s".format("dd/MM/yyyy hh:mm:ss".parse(...))
You want to use
pmList.add(sdfFormat.format(sdfClient.parse(pmData[k].retrievalTime)));
Instead...

Date formatting exception unparseable date

I am trying to format dates entered by my application user using SimpleDateFormat but I always get an error:
01/28/2014java.text.ParseException: Unparseable date: "01/28/2014"
The code I am using to format the date is as follows:
Date rDate, dDate;
String Date1 = request.getParameter("Date1");
String Date2 = request.getParameter("Date2");
//Here the date get display for example as 01/29/2014 (i.e. MM/DD/YYYY)
System.out.println("Date1:: "+ Date1);
System.out.println("Date2:: "+ Date2);
SimpleDateFormat parseRDate = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
SimpleDateFormat parseDDate = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
try {
//#########Crashes in the next two lines#########...
rDate = (Date)parseRDate.parse(Date1);
dDate = (Date)parseDDate.parse(Date2);
} catch (ParseException e) {
e.printStackTrace();
}
Can someone please help me by telling me what I am doing wrong here?
Thanks for your time

You need to match the DateFormat pattern to your input String
SimpleDateFormat parseRDate = new SimpleDateFormat("MM/dd/yyyy");
Any idea how I can convert the format from MM/dd/YYYY to yyyy-MM-dd HH:mm:ss?
All you need to do is use a separate SimpleDateFormat instance for formatting
SimpleDateFormat output = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
System.out.println(output.format(date1));

As you say, Date1 is of the form MM/dd/yyyy... but you're trying to parse it with a format of yyyy-MM-dd HH:mm:ss.
The pattern you parse to the SimpleDateFormat constructor has to match the format of the data itself. (What did you think you were specifying in the constructor?)
Note that the code you've provided isn't doing and formatting at all - just parsing.
You should also work out which time zone you're interested in, and which Locale. Personally I think it's clearer to specify both of those explicitly - even if you want the system default ones.
(If you're doing any significant amount of date/time work, you should also consider using Joda Time, which is a much more pleasant date/time API. I'd also consider more useful exception handling, and following Java naming conventions...)

You specify the format yyyy-MM-dd HH:mm:ss in the constructor and then accept a completely different format (MM/dd/yyyy) as input. You need to make the actual format match the expected format.
Examine the following (for comparison):
Date rDate, dDate;
SimpleDateFormat parseRDate = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
SimpleDateFormat parseDDate = new SimpleDateFormat("MM/dd/yyyy");
try {
rDate = (Date)parseRDate.parse("2014-01-28 12:22:22");
dDate = (Date)parseDDate.parse("01/28/2014");
} catch (ParseException e) {
e.printStackTrace();
}
The string passed to the constructor is what tells SimpleDateFormat how to read the input you give it later.

SimpleDateFormat ParseException : Unparseable date

I'm trying to execute this code:
Date date = null;
if (detailsBean.getDiscoveryProjectBean ().getCreatedDate ()==null ||
detailsBean.getDiscoveryProjectBean ().getCreatedDate ().equalsIgnoreCase(""))
{
projectDetails.getDiscoveryProject().setCreationTime(new Date());
}
else
{
try
{
date = new SimpleDateFormat (FormatUtils.simpleFormat).
parse (detailsBean.getDiscoveryProjectBean ().getCreatedDate ());
} catch (Exception e) {
throw new PanDaApplicationException (e.getMessage ());
}
projectDetails.getDiscoveryProject().setCreationTime(date);
}
in the try block a ParseException exception is thrown. I don't know the cause of that as the code seems fine, however. the definition of the FormatUtils.simpleFormat is public static final String simpleFormat = "dd-MMM-yyyy" and detailsBean.getDiscoveryProjectBean().getCreatedDate() have value like 28-Feb-2013
I really don't have any clues why this exception is thrown and I need help.

My guess is that the problem is the way that SimpleDateFormat uses your default locale - if your locale doesn't use "Feb" as an abbreviated month name, you'll have problems. So if all your data is actually in English, you might want:
DateFormat format = new SimpleDateFormat(FormatUtils.simpleFormat, Locale.US);
format.setTimeZone(...); // See below
date = format.parse(detailsBean.getDiscoveryProjectBean().getCreatedDate());
Note the part about setting the time zone. Again, SimpleDateFormat will use your system default if you don't specify anything else. (You'll get the instant of "midnight in the specified time zone" as the Date value.)
I would also strongly urge you to consider using Joda Time instead of the built-in Date/Calendar types - it's a much better date/time API.

Locale.setDefault (Locale.ROOT);
System.out.println (new SimpleDateFormat ("dd-MMM-yyyy").parse ("28-Feb-2013"));
Locale.setDefault (Locale.forLanguageTag ("ru"));
System.out.println (new SimpleDateFormat ("dd-MMM-yyyy").parse ("28-Feb-2013"));
For me output is:
Thu Feb 28 00:00:00 MSK 2013
Exception in thread "main" java.text.ParseException: Unparseable date: "28-Feb-2013"
at java.text.DateFormat.parse(DateFormat.java:357)
at DateFormat.main(DateFormat.java:19)
So the same date successfully parsed with ROOT locale, but failed with Russian.

Java change date format from custom date to MM dd yyyy

I am trying to convert a String value that is stored in a database,for example "2012-01-20", to be in the format January 20, 2012.
I have seen some examples, but they are using Date which works with SimpleDateFormat.
As an example here is one way I tried but the "try" always fails and the result is null
DateFormat df = new SimpleDateFormat("MM/dd/yyyy");
Date convertedDate=null;
try {
convertedDate = df.parse(datePlayed);
} catch(ParseException e){
e.printStackTrace();
}

In short, you're not using the right format for parsing. You need to use two DateFormat instances; one for parsing and one for formatting.
DateFormat parser = new SimpleDateFormat("yyyy-MM-dd");
DateFormat formatter = new SimpleDateFormat("MMM dd, yyyy");
Date convertedDate = parser.parse(datePlayed);
String output = formatter.format(convertedDate);

Date da = new Date();
SimpleDateFormat ft = new SimpleDateFormat("E, dd/MM/yyyy !");
System.out.println("Update : " + ft.format(da));
You can change your date style do you want at: E, dd/MM/yyyy !
Good luck !

If the Date is read from a Database, then store it as a java.sql.Date. You can then use SimpleDateFormat on it, maybe after converting to java.util.Date. From the ResultSet object, you can extract Dates.
If what you meant is that you are given a date in text that was extracted from a DB by someone else and you are stuck with it. Try using:
DateFormat df = new SimpleDateFormat("yyyy-MM-dd");
df.setLenient(true);
convertedDate = df.parse(datePlayed.trim() );
Also try displaying the text you are parsing before you parse to make sure the datePlayed value is what you expect.
With parseInt, an extra space before or after the data will cause an error, so calling trim() removes extra spaces.

java : java.text.ParseException: Unparseable date

I am reciving a input in this format 2012-01-13T00:00:00.000-05:00 and which i need to convert this into yyyyMMdd Format .
I have also set the SimpleDateFormat.setLenient(false);
This is my coding for parsing the Date
public static String getparsedDate(String date) throws Exception {
DateFormat sdf = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS", Locale.US);
sdf.setLenient(false);
String s1 = date;
String s2 = null;
Date d;
try {
d = sdf.parse(s1);
s2 = (new SimpleDateFormat("yyyyMMdd")).format(d);
} catch (ParseException e) {
e.printStackTrace();
}
return s2;
}
But i am getting a Exception at
java.text.ParseException: Unparseable date: "201201"
at java.text.DateFormat.parse(Unknown Source)
Could anybody please let me know , what might be the issue ?

You are missing the timezone in your format string. If you check the argument, it is finishing with -05:00 and you are also using Lenient==false.

Unfortunately, the time zone formats available to SimpleDateFormat are not ISO8601 compliant. SimpleDateFormat understands time zone strings like "GMT+01:00" or "+0100", the latter according to RFC822. Therefore using SimpleDateFormat does not seem as an option in your case (since you use UTC−05:00 as timezone).
Instead of SimpleDateFormat you need to use JodaTime for that type of date format.