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Parsing from SimpleDateFormat to Date not working?

SimpleDateFormat df = new SimpleDateFormat();
Date lastLogin = null;
try {
String troubleChild = lineScanner.next();
lastLogin = df.parse(troubleChild);
} catch (ParseException e) {
System.out.println("ohnoes");
}
Hi I'm quite new to using the date functions and I've come up with a problem. I have a file that is being parsed into various variables and they all work except this one i can never get it so that it passes the try/catch clause i've looked up similar problems but none of them work on my code.(The date i am inputting is in the format: Mon, Oct 30 22:20:11 GMT 2017) please can I get some help and thanks for it!

Solution: java.time
Please don’t take the trouble with the long outmoded classes Date and SimpleDateFormat. Instead use java.time, the modern Java date and time API also known as JSR-310:
DateTimeFormatter dtf
= DateTimeFormatter.ofPattern("E, MMM d H:mm:ss z uuuu", Locale.UK);
String inputDate = "Mon, Oct 30 22:20:11 GMT 2017";
ZonedDateTime lastLogin = ZonedDateTime.parse(inputDate, dtf);
System.out.println(lastLogin);
This prints
2017-10-30T22:20:11Z[GMT]
Since dates and times may come in so many different textual formats, I am using a format pattern string to specify your particular format. For which letters you may use, and what difference it makes whether you use 1, 3 or 4 of the same letter, see the documentation. Beware that format pattern strings are case sensitive.
Problem: SimpleDateFormat
You used the no-arg SimpleDateFormat constructor. The way I read the documentation, this gives you the default date format for your locale. If your JVM is running UK locale, I believe the format goes like 28/11/17 10:57 — not much like the input format you were trying to parse. You can use System.out.println(df.format(new Date())); to find out. The usual SimpleDateFormat constructor to use would be SimpleDateFormat(String, Locale) so that you may again supply a format pattern string and a locale.

Can't make java.text.SimpleDateFormat to work

I have a Date object as follows:
java.util.Date d = new java.util.Date(System.currentTimeMillis()); // Mon Dec 23 14:57:28 PST 2013
I need to format the date to get another Date object with this format instead:
2013-12-23 14:57:28
I tried this code:
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-mm-dd HH:mm:ss");
sdf.format(d); // d is still Mon Dec 23 14:57:28 PST 2013, no formatting.
I tried this code:
String s = d.toString();
try {
d = sdf.parse(s);
} catch (Exception e)
e.printStackTrace(); // java.text.ParseException: Unparseable date: "Mon Dec 23 14:35:48 PST 2013"
Would you please tell me what am I doing wrong? I googled searched it but the solutions to format a Date was more or less what I tried. Any help is greatly appreciated.

You don't understand what a Date is, and what format() does. A Date is just a number of milliseconds. Nothing more. It doesn't have any format. Formatting a date doesn't change the date at all. It returns a string containing a human readable representation of the date (like "2012-11-23" or "Monday, April 2").
So, the following instruction:
sdf.format(d);
is effectively a noop. You ignore the string that it returns.
If what you want is to have a specific format used when calling date.toString(), it's impossible. When you want to display a date in a specific format (yyyy-MM-dd for example), instead of doing
System.out.println(date);
use
DateFormat format = new SimpleDaeFormat("yyyy-MM-dd");
System.out.println(format.format(date));
All this is clearly explained in the javadoc. You should read it.

SimpleDateFormat, does not change the date format, it gives you a formatted date for display purpose only, not for anything else.
util.Date will always have one format (a long number of milliseconds) that you can format to any way you want in order to display using SimpleDateFormat. So in effect no matter what date you get you can format to what format you want.
If you explain why you are trying to do what you are trying to do, then maybe we can support you better.

Trying to convert yyyy-MM-ddTHH:mm:ss-07:00 to correct time in Android

Okay, so here's my issue in Android right now. On our Database there's a timestamp in this format 8/15/2013 2:00:48 PM and through a .NET WebService I get that same time like this in Android: 2013-08-15T14:00:48-07:00. Now I want to convert this format into a Date Time format that I can use for comparison (for example this webservice provides every instance where a device failed at logging in so we want to check the amount of time between occurances to see if there's any issues). Below I have this code where I'm trying to use JODA Time but it's still not returning the correct format:
public static Date convertStringToDate(String input) {
String pattern = "yyyy-MM-dd'T'HH:mm:ssZ";
DateTimeFormatter formatter = DateTimeFormat.forPattern(pattern);
DateTime dateTime = formatter.parseDateTime(input);
return dateTime.toDate();
//printout shows: Thu Aug 15 17:00:48 EDT 2013
}
I know that the server is returning some crappy time format that is hard to work with (it took a while to get this to work in the iOS App we have, and even there it's still rather clunky) so I don't mind changing the webservice or the query if that would make things easier.

I have a very similar format, and I parse it using SimpleDateFormat, try this:
SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ssZZZ", Locale.US);
Date dateTime = format .parse(value);

What i understand is that you have your correct instance of date already and what you need is to parse it to String.
I suggest you use:
DateFormat formatter = new SimpleDateFormat("d/MM/yyyy hh:mm:ss a");
//this will give you the format '8/15/2013 2:00:48 PM'
String d = formatter.format(date);
Hope this helps.
EDIT:
Also seams you want to have your date instance in -07:00 timezone
So you can change your line
DateTime dateTime = formatter.parseDateTime(input);
for
DateTime dateTime = formatter.withZone(DateTimeZone.forID("-07:00")).parseDateTime(input);

How can I get the current time in particular format, for a particular zone?

I want to get the current DateTime in a zone of my choice and in a particular format (eg HH-MM-SS, MM-DD-YY, MoMo-DD-YY-HH-MM-SS etc).
How can I do this, using JodaTime?

Given that you've already seen the user guide (which includes sections on time zones and formatting), it's not really clear where your confusion is. Some sample code to get you going:
DateTimeZone zone = DateTimeZone.forID("Europe/London");
DateTime currentTimeInLondon = new DateTime(zone);
DateTimeFormatter formatter = DateTimeFormat.forPattern("HH:mm:ss, MM-dd-yyyy");
String text = formatter.print(currentTimeInLondon); // e.g. 08:24:54, 09-26-2012
It would be worth you taking some time to analyze why you couldn't get to this code yourself, given the information in the user guide. Being able to work out how to use APIs is a very important skill as a software engineer - you mustn't expect to be spoonfed code all the time.

this may help you.
http://joda-time.sourceforge.net/userguide.html

Use following code to get time according to particular zone with format.
Locale locale = Locale.FRENCH;
// Format with a custom format
DateFormat formatter = new SimpleDateFormat("E, dd MMM yyyy", locale);
String s = formatter.format(new Date());
// mar., 29 sept. 2012
// Format with a default format
s = DateFormat.getDateInstance(DateFormat.MEDIUM, locale).format(new Date());
// 29 sept. 2012

Date Format - Java

I want to accept a Date format according to an ISO (can't remember which one)...
2009-09-17T13:03:00
How do I do this? I'm currently using a SimpleDateFormat but when I run my unit test against it, it fails.
DateFormat df = SimpleDateFormat("yyyy-MM-ddTHH:mm:ss");
Unit Test is passing it this string:
String test1 = "2009-09-17T13:07:01";

The SimpleDateFormat parameter should be "yyyy-MM-dd'T'HH:mm:ss".
Regards.

You need to enclose the T in single quotes

Your format is wrong. It should be something like this,
SimpleDateFormat isoFormat =
new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss'Z'");

An easy Solution is to remove the "T" ;-)
...
SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-ddHH:mm:ss");
Date date = df.parse("2009-09-17T13:07:01".replace("T",""))
Regards, Jan